BSA MotorCycle Stuff ----------------------- Rev. 3-JUNE-1996 References: "Classic Bike", No 7, Autumn 1979, East Midland Allied Press "Cycle Guide", Vol. 5 No. 3 March 1971, Cycle Guide Magazine, PO Box 267, Mt Morris, ILL "Cycle Guide", Vol. 2 No. 1 January 1968, Cycle Guide Publications, 6675 East 26th St, Los Angeles California, 90022 "American Motorcycling", Vol. VI No. 12 December 1952, the official publication of the American Motorcycle Association, published by the Motorcycle and Allied Trades Association, 120 South State St, Westerville Ohio "Riding Bike in the Fifties", Albert Drake, Stone Press, 1973 "BSA Instruction Manual, Model B44, 441cc O.H.V., Victor Special, Shooting Star, Model C25, 249cc O.H.V., Starfire" 1968, BSA Motor Cycles Limited, Armoury Road, Birmingham II, England, Publication Ref No 00-4139 "BSA Workshop Manual, 250/500 cm3 models, 1971" Publication Reference Number 00-4188, May 1971, B.S.A. Motor Cycles Limited Registered Office Works: Armoury Road, Birmingham B11 2PX, England, covers: B25SS, B25T, B50SS, B50T, B50MX "Replacement Parts List" BSA Model B25 Starfire, From Engine and Frame Number KC.06301.B25S, Catalog Number 00-5197, date 1969, B.S.A. Motorcycles LTD. Service Department, Armoury Road, Birmingham ll, October 1968. "BSA Singles, 250, 350, 440, 500 (Unit) 1958 to 1972", Marcus Daniels, J H Haynes and Co Limited, Sparkford Yeovil Somerset England, 1974, ISBN 0 85696 127 2, Covers: C15, B25, C25, B40, B44, B50 "BSA Unit Singles, 247cc,343cc,441cc,499cc, 1958 to 1972, Owners Workshop Manual", Marcus Daniels, J H Haynes and Company Limited, 1974, Haynes Publishing Company, Sparkford Yeovil Somerset England, ISBN 0 85696 127 2 "Modern Motorcycle Mechanics" seventh edition, J. B. Nicholson, Nicholson Brothers Motorcycles LTD., Saskatoon, Saskatchewan, 1st Ed 1942, 2nd Ed 1945, 3rd Ed 1948, 4th Ed 1953, 5th Ed 1965, 6th Ed 1969, 6th Ed reprint 1973, 7th Ed 1974. "BSA the Complete Story", Owen Wright, Crowood Motoclassics, Crowood Press Ramsbury Marlborough Wiltshire SN8 2HR England, 1992, ISBN 1 85223 702 3 "The Story of BSA Motorcycles", Bob Holliday, Patrick Stephens Ltd, Cambridge CB3 8EL, England, 1978, ISBN 0 85059 227 1 "The Illustrated Motorcycle Legends", Roy Bacon, Sunburst Books, Chartwell Books, Inc., Book Sales, Inc., 1995, ISBN 0 7858 0254 1 "Motorcycling the Golden Years, A Pictorial Anthology", Rupert Prior, Tiger Books International, London, 1994, ISBN 1 85501 342 8 "Motorcycle Classics", Doug Mitchel and the auto editors of Consumer Guide, 1995, Publications International, ISBN: 0-7853-0889-X "Rebuilding the Indian, A Memoir", Fred Haefele, 1998, Riverhead Books, The Berkley Publishing Group, ISBN 1-57322-734-X "BSA M20 & M21 Super Profile", Owen Wright, 1985, A FOULIS Motorcycling Book, Haynes Publishing, ISBN 0-85429-485-6 "BSA Pre-Unit Singles, Owners Workshop Manual", Mansur Darlington, 1993, Haynes Publishing, ISBN 0-85696-326-7 Frames and Engines: The original bike (the BSA) is frame SN# ND 03007 B44 VS. It came with engine SN#: C25 663. Clearly this engine did not originally belong to this bike. Based on the frame serial number the bike was a Victor Special with a 441 engine. I do not know what years the C25 engines were made but clearly with a serial number of 663 this engine must be from the first year of C25 engine production. Also because its serial number is less than 2050, it has the original type of rocker box with spindle springs and spindles that are set with their flats outwards. Based on the front wheel hub assembly this bike frame must be from 1966, 1967, or 1968. This bike has the rod damper type of front forks. The forks were damaged and no longer contain all of the original parts that belong to the rod damper system. This bike came from McGoverns on M37 in the summer of 1973 for $40. The second bike (the Triumph) is frame SN# XD04513 TR25W. The engine has the same serial number. This bike was called a Triumph Trophy. Based on the type of front wheel hub assembly this bike must be from 1968, 1969, or 1970. This frame has the "early" type shuttle valve front forks which were discontinued at the end of 1970. This bike came from "up North". I just found a 1992 book at Schuler's bookstore called, "Triumph Buyers Guide". It lists the TR25W as being made in 1968 through 1970. It has a picture of one, some derogatory comments about its BSA engine (leaking and breaking), and a number of other clues as to which of the three years its is. Both bikes have the same rear wheel hub assembly that was used from 1966 through 1970. Both bikes have the same type of rear wheel swing arm which was also used 1966:1970. Currently the C25 SN 663 is in the TR25W frame but it has the cylinder, the cylinder head, and the rocker box from the TR25W installed on it. Note: the comment about the cylinder head and rocker box is dated. The crankshaft of the Triumph motor has a big end journal diameter of: 1.435". Missing parts to finish putting the TR25W engine back together: Gearbox, Layshaft bearings, needle roller, 0.5" x 0.625" x 0.8125" Torrington B108 Gearbox, Layshaft diameter, left, right, 0.6245" 0.6250" Gearbox, Mainshaft bearing (right) 0.625" x 1.5625" x 0.4735" Hoffmann LS7 or is it LS7 V3 or perhaps L7 V3 Gearbox, Mainshaft diameter (right) 0.6245" - 0.6250" Gearbox Mainshaft Sprocket Side Bearing I think this is a Hoffman 130 and a replacement would be (I think) SKF 6206/C3 This is a sealed bearing. Bearings come from InveTech (sp?) aka Detroit Ball Bearing phone 800-992-7765 Contact Susan pickup at the store at the Lansing store 4302 Creyts Road phone: 322-2010 the B108 is in stock it costs $3.32 the LS7 is harder to get (i.e. it takes one week) and costs $10. British Motorcycle Companies: Before WWII there were about 30 motorcycle manufactures in Britan. After WWII the remaining companies formed into "groups". This progressed from the mid 50's to the late 60's. The groups included: The B.S.A. group, which was: Ariel, B.S.A., Sunbeam, Triumph. The A.M.C. group, which was: A.J.S., Matchless, James, Francis Barnett. The Norton Villiers group. The A.M.C. group was subsequently absorbed into the Norton Villiers group. The final group was called Norton-BSA-Triumph which died about 1974 In the early 60's the British motorcycle industry benefited from the Japanese entry into the field. Initially the Japanese made only small bikes and many people moved from these up to larger British machines. The Japanese also made motorcycles more socially acceptable so a wider range of people were interested. The British motorcycle companies included: A.J.S. A.J.Stevens, stated early, died 1966, 1939 water cooled supercharge V4 Ariel Started production in late 1890's, ended in 1963, Square Four in 1931 Brough B.S.A. Started early, was the worlds larges for a while, died in 1973 Dot Douglas Excelsior Francis Barnett Greeves James Levis Matchless Started in the first years of 1900, died 1964-1968 New Imperial New Hudson Norman Norton died 1974 as part of the final Norton-BSA-Triumph amalgamation O.E.C. O.K. Supreme Panther Rickman this company started late in the motorcycle business Royal Enfield remained independent until it died Rudge Sun Sunbeam died about 1959 Superior Triumph Edward Turner did the designs in the 1930's, company died 1974 Velocette remained independent until it died Vincent died mid 1950's Villiers Wassell The only ones that I have seen in the U.S. are: BSA, Matchless, Norton, and Triumph. Continental European Manufactures: Germany: B.M.W., Maico, Zundapp, N.S.U. Italy: Aermacchi, Ducati, Moto Guzzi, M.V.Agusta, Gilera, Benelli, Laverda Spain: Ossa, Bultaco Sweden: Husqvarna Czechoslovakia: Jawa I believe that most of these companies still existed in the mid-late 1960's. In the U.S. one used to see: BMW, Moto Guzzi and its clear that Zundapp and Bultaco were also here. France: Motobecane. Mostly small two cycle machines (the worlds larges manufacture of these). In 1974 they made a 500 cc 3 cylinder two cycle with electronically controlled fuel injection. This went a long way to eliminate the problems of two cycle engines; excessive fuel consumption and exhaust pollution. What became of this Motobecane product? Other French companies? \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\/////////////////////////////////////// From: MSUPA::LAURENS "Philippe" 12-SEP-1995 15:32:36.29 To: MSUPA::EDMUNDS, gross CC: LAURENS Subj: RE: European Motorcycles, please fill in French part. I know that Ossa were known for the kind of bikes called "trial" in French. That was the "only" serious trial bike. That's the sport where you have to climb up trees, rocks and such at 1/8 mph without setting your foot down. Bultaco was known in France for its enduro bikes (i.e. competition dirt) Another name I remember for enduro bikes is KTM, I don't know where they come from. I can also remember Puch (sp?) german? I didn't see Vespa in your list. I don't know if they made real bikes. I also think their full name was longer than just Vespa. There also was a make of mopeds called Fuchs (sp?) I think it is German as it means fox in German. From: MSUPA::LAURENS "Philippe" 12-SEP-1995 15:37:28.81 To: MSUPA::EDMUNDS CC: LAURENS Subj: RE: European Motorcycles, please fill in French part. Montesa is another spanish (I believe) make of "trial" bikes From: MSUPA::LAURENS "Philippe" 13-SEP-1995 13:17:02.86 To: MSUPA::EDMUNDS, gross CC: LAURENS Subj: RE: European Motorcycles, please fill in French part. I went to get the motorcycle booklet from the Sec.of.State and I had to ask for it. It is behind the counter because...?... it hasn't been reprinted and still has Austin's face on it. After that I wandered off to Curious and looked at their motorcycle books. There are a few neat books about Harleys and Indians. There is a VERY nice, thick, British book about the history of motorcycles with an index of all companies, and also a list by periods... but Ray wants $25 for it. Maybe we could pool some money. France: Terrot (20's ? - 60's) MF (81-82 "superbike" with a car engine) Peugeot (since 1899) made scooters too, only small bikes <250cc since the war, only moppeds now. Motobecane (since the 20's) There were a couple companies I had never heard of that seem to have been around in the 20's or 30's only. e.g. Lutece (with and accent, this is the old name for Paris). That's about it. Overall very few French motorcycle companies compared to GB. It also looked like at the begining of the century bikes were made mostly for racing and not necessarily sold to the public, or other racers. More motorcycles from a 1979 guide Italy: Lambretta (scooters) Austria: Puch, KTM (West-)Germany: Hercules, and others that I already forgot (Kroeddel I think) Spain: Isn't Ducatti spanish? There was another spanish name like that, but now I am not sure I remember right. Dan listed it as Italian. There were a couple Russian bikes. \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\/////////////////////////////////////// Advance Mechanism and ignition points cam from the Triumph The advance Mechanism is labeled 10 Degrees. But did this label imply crank or cam shaft degrees? As found the springs were stretched to the point that it does not return to the non advanced position. The slot in the wheel that controls the range of travel of the cam relative to this wheel looks like it has been "stretched" from having the cam pin beat on it. Two measurements of the dimensions of the advance mechanism were made about two weeks apart. Slot Length --------------------------------- Pin Dia Radius to Pin Not including "D" Including "D" ------- ------------- ----------------- ------------- 1st measurement 0.180" 0.6425" not measured 0.350" 2nd measurement 0.180" 0.635" 0.322" 0.355" The first measurement --> 15.2 degrees of movement. The second measurement --> 12.8 degrees without the "D" and 15.8 degrees with the "D". It is fairly clear but not certain that the "D" shape extension in the slot was caused from the pin beating on it for hours at at time. The pin itself does not look distorted, but it may be much harder material. The slot looks stamped in the wheel. The cam has radial slop where it mounts over the spindal on the advance wheel. This measured radial slop is about 5 or 6 mills. So how many degrees of rotation does this translate into? The big to big diameter of the cam measures about 0.745" and the big to little diameter measures 0.707". This implies a lift of 38 mills which does not fit exactly with the measured (on the lath with a dial gauge) lift of 50 mills. Lets picture the lift ramp from small diameter to large diameter being at 45 degrees. So if the average diameter is about 0.726" then the circumference is 2.280" and with 45 degree ramps a 5 mill radial slop is only 0.8 degrees of ratation. Note that this analysis is in disagrement with the Workshop Manual which says on page B22 that 1 mil is 1 degree. \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\/////////////////////////////////////// Bore: 67 mm Stroke: 70 mm Compression Ratio: 10 to 1 Ignition: 37 degrees or piston short of TDC by 0.342 inches Full Advance is reached at: 4250 RPM Connecting Rod Length Between Centers: 5.312 inches \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\/////////////////////////////////////// Steve has a Yamaha Virago XV750 1982 Philippe has a Yamaha Xt500 1978 Sears Allstate was most likely made by Puch as Austrian company ALLSTATE / Austria 1953-1963 This is the name of the Austrian Puch machines sold in the USA since about 1953 by Sears-Roebuck of Chicago through their nationwide branches. Allstate is a Sears trademark, also applied to car parts, insurance, etc. PUCH / Austria Johann Puch's factory at Craz Austria, started by making bicycles in 1899 and rapidly expanded over the next decade, producing cars,lorries and even railway locomotives by 1914. The sturdy, conventional four-strokes, singles and V twins of between 300cc and 800cc were therefore only a minor part of Puch's output. During WWI Puch concentrated on armament manufacture, but after it, eventually decided to concentrate on bicycles and motorcycles. For the latter, a design by Giovanni Marcellino for a 175cc "split single" two-stroke engine of 175cc was chosen and though the design was to be altered and updated continuously, this engine configuration remained in use for the next 50 odd years. It powered the original Puch 'Harlette', a spindly affair characterized by the British magazine "The Motor Cycle" as a 'motorised bicycle', but it did have a two-speed gear and clutch, in the rear hub. Almost from the start, Puch raced in the 175cc and later the 250cc class, using an auxiliary charging pump and, on later models, water cooling. The 250cc Puch's finest hour was the 1931 German Grand Prix, when Elvetio Toricelli won the 250cc class beating the works New Imperial, Rudge and Excelsior teams and convincing DKW that the 'blown' split-single was their future salvation in racing. Unfortunately, Puch were badly hit by the depression of the early 1930s and withdrew from racing. Split single two-strokes were Puch's strong point in the 1930's, although a flat four-cylinder four stroke model was introduced in 1936. Manufacture of this was dropped after WWII, though the split singles continued to be made in various capacities. In the 1960s, however, new more orthodox, two-stroke engines appeared in the 50cc to 125cc capacities, while production diversified into small scooters, off road machines and mopeds. Puch had long since had a reputation in the ISDT-type events, and the new models were just as successful - and in moto-cross as well, with new 250cc designs. In the late 1970s Puch began to use two-stroke and four stroke Rotax engines for competition models, but more and mote the 50cc class beckoned with ready sales of motorcycles and mopeds. The Puch Maxi moped was a world best seller in the early 1980s. However, Puch were no more proof against the decline of the motor cycle market than the other European motor cycle manufactures and sales fell off badly in the late 1980s. In 1991 Puch were taken over by the Italian company Piaggio and now only make mopeds. "The New Illustrated Encyclopedia of Motorcycles", Edited by Erwin Tragatsch, Revised by Brian Woolley, 1994, ISBN 1-55521-809-1, Wellfleet Press, A Quarto Book. \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\/////////////////////////////////////// 15-FEB-1996 Order the valve lifter for the Triumph engine from British-Only. Cost 35$. They say the Triumph engine serial number is from December 1969. Phone Number direct 313-422-7614 The part number for the valve lifter is 70-7739. Talked with a woman named Rachel. I expect that the real part number is 01-70-7739. It is described in the invoice as a "TR25 Tapped to 1970". It is the old thin style. Measure the slope of the foot of the valve lifter vs the stem. position Delta distance position Delta distance on foot up the stem on foot up the stem ---------- --------------- ---------- --------------- 0.000 0.000 0.000 0.053 0.100 0.007 0.100 0.047 0.200 0.014 0.200 0.040 0.300 0.021 0.300 0.033 0.400 0.029 0.400 0.026 0.500 0.036 0.500 0.020 0.600 0.043 0.600 0.013 0.700 0.051 0.700 0.006 0.800 0.058 0.800 0.000 So this is about sin 56/800 or 4 degrees \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\/////////////////////////////////////// 19-FEB-1996 Measure the old BSA piston and cylinder (1/2mm aka 20 mil OS) before starting any work: Piston: On thrust surfaces: top of skirt 2.652 skirt at pin elivation 2.653 skirt 1/2" from bottom 2.656 skirt at bottom 2.655 90 degrees to thrust surfaces 2.647 Cylinder: On thrust surfaces: Very bottom for now 1/2 inch in this is mid ring wear all about very top 2.659 - .660 Measure the gap in the 2nd ring at three locations: 1/8 inch from top 0.017 mid stroke 0.021 1/4 inch from bottom 0.018 This implies only about 1 mill of wear in the cylinder. Specifications for piston cylinder clearance: from red book: 2 1/2 mil bottom, 5 mil top from 1971 shop manual: ring gap should be 0.009 to 0.013 inches. from 1971 shop manual: the piston to cylinder clearance should be 2.5 to 2.8 mil bottom, 4.2 to 5.3 mil top this would imply: std 1/2mm 20 mil OS -------------- --------------- Cylinder bore 67mm 2.6378" 2.6578 piston top skirt 2.6330 2.6530 piston bottom skirt 2.6351 2.6551 So from this it looks like the old BSA piston is just about the proper size (perhaps the top of the skirt and the very bottom of the skirt could be brought up 1 mill). It looks like the cylinder bore it too big by about 2 mill. This puts the clearances off by about 3 mill which is the service limit. Action taken on the BSA cylinder and piston: Knerel the piston hard, lightly sand off the obvious burs with 280 grit paper and measure it again. The new numbers measured on the thrust surface are: Top of skirt 2.659 1/4" down from top of skirt 2.658 middle of skirt 2.659 1/4" up from bottom of skirt 2.661 bottom of skirt 2.658 So lets assume that the cylinder is 2.660 bore so continue to sand the piston skirts to get the following: Top of skirt 2.655 25 middle of skirt 2.656 3 bottom of skirt 2.657 35 Some weeks later, remeasure the ring gap: ring gap mils Top i.e. no ring wear 18-19 3/4" down upper part of all 3 ring wear 22-23 1 3/4" down middle of ring stroke 21-22 2 1/2" down lower part of all 3 ring wear 21-22 Bottom i.e. no ring wear 18-19 Sand the piston and measure again: Top of skirt 2.655 or 2.6545 pin center 2.656 1/2" up 2.656 1/4" up 2.656 very bottom 2.655 60 teath on cam gear and 30 teath on crankshaft pinion. The "dash" and the "V" on the cam gear are separated by two teath. Put a timing dot on the Triumph rotor at 10 degree intervals. These dots were put down at a radius of 1.340". The dots at 0, 50, 100, 150, 200, 250, and 300 degrees are "double dotted". The index head is 9 degrees per turn. A turn can be divided into either 15, 16, 17, 18, 19, or 20 pieces. OK, the clutch rack that came with the Triumph does not belong to a B25/C25. It is way too long. cases did not close by about 0.350 with no push rod push rod sticks out about 0.150 inch (i.e. minimum stroke required to disengage the clutch) full diameter of rack 0.544 diameter of rack from a low spot in a tooth to the opposite smooth side 0.457 Length of rack 1.220" Depth in casting to hold the rack 0.8 Diameter of the push rod 0.1875 Cable stroke due to pulling the clutch hand lever 0.600" The radius of the leaver arm on the clutch cable connection is about 1.550" The radius of the clutch pinion mechanism is about 0.340" Ratio of the lever arm to pinion radii is 4.56 to 1 So the clutch rack moves about 0.6" / 4.56 = 0.131" So, at full engagement, having the rack about 0.15" from the end of the main shaft makes sense. Using a ball with a diameter of 0.218" Reduce the length of the rack to 0.75" The rotor is loose on its hub. Viewed from the primary drive side the rotor should rotate CCW WRT its hub to be in the position of normal alignment. Threads on the oil pressure switch: Made two measurements of the threads per inch: 7 threads in 0.263" --> 26.6 tpi 8 threads in 0.295" --> 27.1 tpi Diameter is about 0.390" The key for the keyway that holds the alternator rotor on to the crankshaft and the key for the clutch hub to mainshaft attachment both have the same dimensions which are: about 0.158" thick and about 0.565" long. In the BSA head Measurement of the valve stems and the valve guide inner bore diameters: Intake valve stem 0.310 all along its length except right nead the top of the stroke 0.3095 Exhaust valve stem 0.311 all along its length except right nead the bottom (or below the bottom) of the stroke 0.310 a rod of 0.315 will fit about 1/4" into all valve guides except into the top of the intake valve guide. It is loosest in the exhaust valve guide. In the exhaust valve guide it rocks the most in the obvious direction of the racker arm push. So the clearance of the valve stems in the valve guides looks like about 4 or 5 or more mils. So on 28-MAR-1996 order new valves for $22.95 each and new valve guides for 14.85 each. Order from British Only 313-422-7614. Ordered for TR25W from 1969. Parts received on the above order on 29-MAR-1996 Exhaust Valve 70-7777 $ 29.04 Inlet Valve 70-8112 $ 22.95 Exhaust Valve Guide 70-8225 $ 14.85 Inlet Valve Guide 70-8226 $ 14.85 All parts look new and of original manufacture. The top of the stem of the exhaust valve is stamped "N80 EX" just like I have seen on some other exhaust valves. The top of the stem of the inlet valve is stamped "Made In England V255". The inlet valve included a blue piece of paper that says, "Inlet Valve V.255 for BSA 1966 Model A50. Replacing Original Part No. 68-0661". I do not know if this was just a loose piece of paper in the un-seeled plastic sack that the valve was packed in, or if this means that B25 valves and A50 valves are the same. 3-APR-1996 Install the new valve guides with heat sink compound in the BSA head. 4-APR-1996 Take the BSA Head to Jerry at Shep's to get the valve seats cut. 11-APR-1996 Get the BSA head back from Shep's. At first all looks OK but on careful examination there are a number of problems: There is still one big pit in the exhaust valve seat. There are still some very small pits on the inlet valve seat. Both inlet and exhaust have been lapped so much that there is a cylindrical recess in the valve seat. Neither seat has had the benefit of blending cutters. Because the valve keepers have sunk down into the top valve spring washers, make inserts that go between the valve keepers and the top valve spring washer. These inserts are made from 0.005" to 0.006" brass shim stock. Numbers on various of the original BSA parts: Piston 40-971 Rocker box 40-961 Barrel "L" FINAL Measurements of the BSA cylinder and piston: 14-APR-96 Piston: Location Diameter ----------------------------- ---------- Very very top 2.653 - 2.654 Just under the oil holes 2.655 bump near the top of the pin 2.656 center of the pin 2.655 bottom of the pin 2.6555 - 2.656 1/4" up from the bottom 2.6555 - 2.656 1/8" up from the bottom 2.655 very bottom 2.654 Cylinder Location Diameter ----------------------------- ---------- Very top 2.6595 Just under the ridge 2.661 1/4" under the ridge 2.6605 1" under the ridge 2.660 bottom of ring sweep 2.6595 center of the non ring sweep 2.6585 very bottom 2.6585 Spindles in the BSA rocker box: The Flat is on the same side of the spindle as the high point in its cam. The oil holes are on the opposite side from the flat. Recall that the pre SN #2050 C25's spindles are adjusted with their flats outward. `'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`' Carburetters: As Found Monoblock Concentric Carburetter Carburetter 1971 Specification from the from the BSA of the Carburetter Triumph Characteristic Engine for the BSA Engine Engine ------------------ -------------- ----------------------- -------------- Type RB 930/38 Amal Concentric 928/20 389 Pilot Jet (mm) ? - 30 Main Jet (mm) 200 200 260 Needle Jet (inch) 0.106 0.106 0.106 Needle position top grove 1 ? Needle 2 marker rings ? D Throttle Valve 928 3 1/2 3 1/2 389 3 Choke Diameter 30 mm 28 mm 1.125" - 28.6mm Throttle Valve Spring Length ? 2.5" ? Other opinions about what carburetor should be on a C25 or its relatives. BSA Haynes Owners Modern Instruction Workshop Manual Motorcycle Manual BSA Unit Singles Mechanics 1968 -------------------------- 250 Starefire 250 Starefire 250 250 Characteristic B25 / C25 B25 / C25 Star B25 / C25 ------------------ ------------- ------------- --------- -------------- Type ? Concentric Monoblock Concent 928/20 Pilot Jet (mm) ? 25 ? ? Main Jet (mm) 170 200 140 200 Needle Jet (inch) 0.106 0.106 0.1055 0.106 Needle position ? 2 3 1 Needle ? ? ? ? Throttle Valve 3 3 4 3 Bore Diameter 28 mm 28 mm ? 28 mm The collection of Monoblock pilot jets includes: 25 and 30. The collection of main jets (which appear to be the same for Monoblock and Concentric) includes: 190, 200, 240, 260, 280. All of the needle jets that I have appear to be 0.106". Monoblock type 389 carburetors are make in sizes: 1 1/8, 1 5/32, and 1 3/16. The needle for a Monoblock type 389 should be stamped with the letter "D". The Monoblock series was introduced in 1955. There is another badly corroded Monoblock body in the basement. It is a Monoblock type 376. The Concentric series from Amal was introduced in late 1967. Make and Air Filter mounting plate for the Monoblock 389 carburetter. The OD on the monoblock carburetter intake is between 1.734" and 1.741". It has 24 threads per inch. The ID on the intake stack for the monoblock carburetter is between 1.710" and 1.714". So, the hole in the air filter mounting plate was bored to 1.710" and then the threads were cut about 0.015" deep. The aluminum plate from which this air filter mounting plate was made started out about 0.485" thick. To operate the air slide on the monoblock carburetter get a shifter lever from a mountain bicycle. The lift required to fully open the air slide is 1.125". The diameter of the cable cylinder on the mountain bicycle shift lever is 0.90", i.e. 2.825" circumference. So the lever will have to move through 1.125"/8.825" x 360 deg = 143 degrees to fully open the air slide. Opening in Opening in the the Component Component to Control Cable As Found to Hold the Hold the Cable Inner Wire Cable Stop Component Cable Stop Inner Wire Diameter Diameter --------- ------------- --------------- ------------- ---------- Air Slide 0.137" 0.082" 0.048" Throttle 0.153" 0.070" 0.061" 0.138" The Diameter of the center hole in the cable adjusters on the top of the monoblock carburetter is 0.136". So let's make all the cable stop diameters right at 0.135" so they will fit through the carburetter top cable adjusters. Air_Filter The air filter that had been used on the BSA since it was first put together in the 1970's has: OD 4.0", ID 2 3/4", Height 2 1/8". Muffler The muffler that had been used on the BSA since it was first put together in the 1970's has: OD 3.0", Length Overall 15", Length of the cylindrical section 12". The exhaust pipe has an OD of 1 3/8". Gas Tank Petcock (June-1997) The petcock that has been used all along was leaking a little. Take it apart, clean, and put back together with some silicone grease. It now appears OK but its plastic insides have rotted somewhat. Rebuild one of the all metal petcocks from the Triumph. This takes an "O-ring" which is I guess 1/16, 5/16, 7/16. The plastic rotor petcock has no O-ring. `'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`'`' Part Number from Parts on the BSA Engine: Primary Cover: 40-1003 Alternator Rotor 10-71 54215824 Stamped on both halves of the crank case at the bottom 578 Piston from the Triumph Cylinder that was on the BSA Engine 40-971 40-973 1/2 mm OS BSA label was on the CAM side Measurement of the Triumph Cylinder and Piston that was on the BSA Engine: Piston: Location Diameter ----------------------------- ---------- Very very top 2.653" Top of the pin 2.6535 center of the pin 2.654 bottom of the pin 2.6545 1/8" up from the bottom 2.656 very bottom 2.656 Cylinder: 2.658" along its full length Re-Measure the Triumph Cylinder and Piston that was on the BSA Engine: It is being reinstalled on the BSA engine (spring 1996) but this time with the BSA cylinder head and rocker box. Piston: Location Diameter ----------------------------- ---------- 1/8" from top 2.653" center of the pin 2.6535 1/8" up from the bottom 2.6555 or 2.656 Cylinder: 2.658" along its full length It not clear how the tapered #2 compression ring should be installed. It had been installed with the fattest thickest part up. I'm going to install it with the fatest thickest part down. I can not really find a "T" mark on this ring any where. But if the little dots that I can see are the remains of the "T" mark then the fatest thickest part should be down. As far as I know the old knreled BSA piston ran with it #2 compression ring with the fatest thickest part down. On the BSA engine the BLACK push rod is the short push rod to use with the Exhaust (inner lifter). On newer engines this is RED. On the BSA engine the WHITE push rod is the longer push rod to use with the Inlet (outer lifter). On newer enginer the inlet push rod is not painted. 29-MAY-1996 The headlight is a Lucas "700 headlamp". The light bulb in it is a 12 V 50/40 W Lamp No 446 by a company that looks like "BTH". The small "pilot" lamp looks like a normal baonet base. The connecting "blades" on the standard headlight that had been used are 5/16" wide, 1/2" deep, and 1/32" thick. .............................................................................. 6-OCT-1996 Work on the front wheel with the full width break. The pin wrench uses 0.175" diameter pins and the pins are spaced 1.564" center to center. The wheel bearings as removed are: FAFNIR 204K-C4 The Hynes book says that these bearings are: HOFFMAN 120 Making a replacement air intake cover. The radius from the axil center to the cover location is about 4.075". The slope of the cone shape of the air intake cover is about 0.084" per inch of height. This implies that the radius of the flat sheet that is cut to for the new cover should be 48.7 inches. The width of the flat sheet that is cut for the new cover needs to be at least 1.150 inches. From the photo in the Hayens book it a looks like the holes in the air intake are in horizontal and vertical rows (after the intake cover is bent into shape) tand that the center to center distance of the holes is 0.140". It does not look like the holes are on an interlaced grid. The holes maybe square or the cover may have realy been a screen held in a frame. I will try 0.090" diameter holes on a 0.140" curved grid. March-1997 replace the wheel bearings in this front hub with 204 bearings from Detroit Bearing. Replace the front air intake cover with an original one optained in Feb-Mar 1997 at the motorcycle swap meet. The outer axil nut on this hub is 1 1/8" flat to flat. The two ball bearings for the front wheel cost $5.26 each. They actuall are Fafnir 204K bearings. The distance between the inner surfaces of the forks for the full width break hub is between 5 3/16 and 5 1/4 inches. \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\/////////////////////////////////////// Production Dates of Unit Singles C15 was the first unit signle. First shipped in September 1958. C25 (called the Barracuta) first shipped in November 1966. It only lasted for one year (I think). B25 first shipped in 1967 and lasted to the end in 1971-72. Parts order from sometime in the 1970's (probably from the Triumph head rebuild). Piston $ 32.50 Valves: Inlet E8112 $ 6.24 Exhaust E7777 $ 11.24 Valve Guides: Inlet E8225 $ 6.94 Exhaust E8226 $ 6.94 Rocker Arms: Inlet E7790 $ 14.94 Exhaust E7791 $ 14.94 Gearbox Sprocket 16 teeth T-2701 $ 19.92 Never purchased but the part number and price for the transmission main shaft are: Part number 57-4344 and the 1973 cost was $23.00 13-JULY-1997 kickstart return spring breaks in the BSA motor. Order a new one from British-Only. It is part number 57-2687 and cost about $10. <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> Electrical Work April 1997 Ford coil Autolite FAC-12029-A 8KBB Resistance Check Dist to Bat 1.43 Ohms HV to Dist 8,132 HV to Bat 8,134 ---> The HV secondary is connected to the "Dist" terminal. The "Motors Manual" says for 1971 to 1974 standard Ford ignition coils that the primary resistance is 1.40 to 1.54 Ohms and the secondary resistance is 7,600 to 8,800 Ohms both at 75 degrees F. The ignition ballast resistor is 1.30 to 1.40 Ohms. The engine stopped primary current specification is 4.5 Amps and the engine idle current specification is 2.5 Amps. 12.6 V battery and 4.5 Amps --> 2.8 Ohm and 2.8 Ohm total - 1.45 Ohm coil = 1.35 Ohms ballast i.e. you get back the ballast resistor value "Engine stopped" primary current vs ballast resistor value: For a 6.0 Ohm ballast and 12.6 V you get 1.69 Amps or 38% of normal For a 4.075 Ohm ballast and 12.6 V you get 2.29 Amps or 51% of normal Check of two old conventional ignition capacitors: Specimen #1 0.242 uFd Specimen #2 0.456 uFd Check the Triumph engine capacitor that came on the breaker plate in the Triumph engine. 0.??? ufd The capacitor on the "electronics shelf" looks like an old generator capacitor more than it looks like an ignition capacitor. It measures 225 nF i.e. 0.225 uF. The electronics is running positive ground. The electrolytic capacitor measures a time constant of about 200 msec with a 10 Ohm resistor which implies about 20,000 uFd. "Reform" it to 18 Volts. Change the ignition shelf: add a second capactior and change the ballast resistor. Now the rear capacitor with the screw mounting terminal is 0.225 uFd and the front capacitor with the all wire terminal is 0.457 uFd. This ballast resistor is now 4.1 Ohms. Most wiring diagrams that I can find show the coil's HV seconday returned to the "battery" terminal; this includes 1970 Delco diagrams and 1940 positive ground Ford diagrams. The BSA workshop manual show the HV returned to the breaker contact terminal. 25-MAY-1997 Test the old lawnmower gell cell battery. Use a resistor that started at 6.8 Ohms and dropped to about 6.0 Ohms as it got quite hot. Make a two minute test. Under load it started at about 12.5 Volts dropped to about 11.6 Ohms and was back up to about 11.9 Ohms under load at the end of the 2 minute test. At the end of the test without load it was at about 13.08 Volts. So at the end of the test under load it was delivering about 11.9 Volts / 6.0 Ohms = 1.98 Amps. So this should be OK for startup. 1-JUNE-1997 The old lawnmower gell cell battery is a GATES Cyclon. The numbers on it are: 0819-0024 12V 2.5AH 7320 J. 23-APR-1998 Startup of the BSA. Transmission oil was down. Primary chain oil was down or empty. The primary chain level check screw is the first screw CCW from the front most (i.e. the front horizontal center line screw. The primary case drain screw is the second CCW from the front most screw. Has the new muffler. Started on 3 kicks. Lots of smoke until it pumped out the oil in the crank case. 2-MAY-1998 Brass gas valve that was completely full of dirt and rust and gas tar. EW Pat. No. 909737. ?-summer-1998 Give up on BSA gas valves and use a commercial one with a teflon seal. 27-SEPT-1998 Change oil. Adjust timing for the nth time in the past month. Timing had been moved as much as about 3 degrees advanced from its 1997 and first part of 1998 position. That initial position had been obtained by the static method. Now it is set 1 or 2 degrees retarted from that initial position and seems the happiest that it has been since starting to run in 1997. 11-OCT-1998 Status of one (#1) of the spedometers. This one has never been opened up but there is a crack forming in the chrome plated ring that holds the front cover glass on. This one reads from 10 (0 or 5?) to 120 (125) mph. Its odometer reads 03424.7 miles and the trip odometer reads 000.3 It is a SMITHS and the small writing at the bottom of the front dial is: SSM5001/03A 1600 MADE IN U.K. L. The small paper tag on the back reads: 690 or is it 069. A quick manual test shows that it takes about 150 turns to increment the odometer by 0.1 mile, i.e. about 1500 turns per mile. Status of the other (#2) speedometer: On its dial it says: SSM5001/05 1000 Made in U.K. L. It goes from 10 to 150. It reads: 02773.9 on the odometer and 307.5 on the trip odometer. On the back it has a small paper sticker that says: 059. It does not appear to have ever been opened up. The parts manual for a 1969 B25 says: mph speedometer SSM.5001/03 19-2181 kph speedometer SSM.5001/04 19-2183 mph drive gearbox BG.5330/31 19-9212 2 to 1 ratio I'm not sure which speedometer came with the original BSA. I do not know if the other speedometer came with the Triumph or out of some 1970's garadge junk. I'm not sure which if either speedometer matches the rear wheel speedometer cable drive gear currently on the BSA. From reading the parts book the best estimate is that the speedometer drive cable turns twice as fast as the rear wheel. The rear wheel speedometer cable driver gear box thing is also by SMITHS. Approximate measurement indicates the rear wheel is 26" diameter --> 81.68" circumference and thus the rear wheel turns 775.7 time per mile. 17-OCT-1998 Now a good measurement of the current wheels shows that the front is a 3.25 x 19 and the rear is 3.50 x 18. A semi careful measurement of the rear wheel indicates a 80 3/8" circumference implies 25.58" diameter. This is 788.3 turns of the rear wheel per mile. At the same time measure the Schwinn wheel. It is a 27 x 1 1/2" for the S6 or K2 rim. It measures 85 1/2" circumference which implies 27.22" diameter. The diameter of the bicycle rim itself is very approximately 25 1/2". Test the two Smiths spedometers and the new bicycle spedometer using a lath to spin them. Setup the new bicycle spedometer as follows: what to match the BSA 80 3/8" circumference rear wheel. Because of the 1 to 2 drive divide 80 3/8" by to then convert to mm which is 1021. So the factor for the new bicycle spedometer is 1021. On the lath the new bicycle spedometer reads 22.4 mph The #1 Smiths reads 27 mph and in 3 minutes its odometer goes 1.1 miles so from its odometer it should have read 22 mph. So this checks. The #2 Smiths reads 40 mph and in 3 minutes its odometer goes 1.75 miles so from its odometer it should have read 35.0 mph. This comparison of readings is exactly what I think you would expect: #1 is 1600 turns per mile and went 1.1 miles #2 is 1000 turns per mile and went 1.75 miles So this cross checks. During all of this I think that the lathe is running at about 585 rpm. Now set the lathe to run at 900 rpm. This causes the #1 Smiths to read 41 mph. For the odometer to increment the one mile takes about 107 seconds which implies that it is going 34.1 mph. With the bicycle spedometer set for a factor of 1021 it reads 34.5 mph. At the highest lathe speed the bicycle speedometer does not work. The #1 Smiths reads 64 or 64.5 mph and it takes 67.5 seconds for the odometer to go one mile. Thus from time and the odometer the speed is 54.2 mph Summary for the #1 Smiths Bicycle Number #1 Smiths Smith Bicycle Speedometer ------------------------------- vs vs Lathe ----------- Speedometer Speed from Timing Smith Smith Speed RPM Speed Reading the Odomter Ratio Ratio ----- --- ----- ----------- ----------------- ----- ------- 1 585 22.4 27 22 1.23 1.21 2 900 34.5 41 34.1 1.20 1.19 3 - - 64 54.2 1.18 - Translation Table for #1 Smiths: Actual Indicated Speed Speed ------ --------- 25 30.5 35 42.0 45 53.5 55 65.0 65 76.0 ?? 7-NOV-1998 Retard the timing another 2 degrees or so and it is running even better. It clearly had been knocking. Big question is how much does the point's gap change when the breaker plate is moved and this gap change causes a timing change that is in addition to that caused by the breaker plate movement. 8-NOV-1998 Diameter of the ignition contact breaker plate is 2.7" in diameter; actually it appears to be 2.690" diameter and I expect that the boar in the This makes 1 degree of rotation of this plate equal to a 0.0236" movement at the circumference of this plate. The plate from the Triumph engine (a dual contact plate) has 47634 stamped on the back. The auto-advance assembly from the triumph engine is stamped 10 degrees, it has no other numbers, it does advance the timing in the proper CCW direction. Measuring the lift on the Triumph ignition cam gives a 0.040" lift. Order of magnitude about 20 mils of this lift occurs in about 15 degrees of rotation. "Standard" B25 Spark Advance Control The standard setup is for a maximum advance of 37 degrees at 4250 RPM. I'm quite sure that this is crankshaft degrees and RPM. This comes from a Lucas 54419653 auto advance mechanism which gives 12 degrees of CCW advance. I'm prety sure that this is camshaft degrees which implies 24 degrees of crankshaft advance control. This gives a spark timing at idle, e.g. 500 RPM, of something like 13 degrees advanced. The highest speed that I have ever seen mentioned for the B25 is 8400 RPM and I'm sure that it should not really operate at that speed. Make fancy new measurements on the cam of the auto advance mechanism from the Triumph engine. This mechanism says 10 degrees and has no Lucas part number on it. Measurements show: total lift: 37.8 mil 0.96 mm Dwell time closed with a 15 mil points gap is: 157.5 camshaft degrees i.e. closed 43.75% of the time slope closing: 1.43 crankshaft degrees per mil slope opening: 1.37 crankshaft degrees per mil 16-NOV-1998 BSA Engine has Alternator Rotor 10-71 54215824 Triumph Engine came with Alternator Rotor 10-69 54212006 which has a loose hub. 16-NOV-1998 Camshaft Journal Diameter and Bush I.D. and O.D. B25 & B50 B44 & Older B Series ? ------------- ---------------------- camshaft time side 0.7480-0.7485 0.7480-0.7485 shaft dia drive side 0.7480-0.7485 0.5598-0.5603 bush time side 0.7492-0.7497 0.7492-0.7497 bore dia drive side 0.7492-0.7497 0.561 -0.562 bush O.D. time side 0.908 -0.909 0.908 -0.909 drive side 0.908 -0.909 0.719 -0.720 clearence time side 0.0007-0.0017 0.0007-0.0022 drive side 0.0007-0.0017 0.0007-0.0017 28-JAN-1999 Order from British Only two more parts books: 1970 B44VS 01-00-5708C 1972 B50 01-00-5732C Feb-99 Order parts. In some cases the parts received match the Parts Book description better than they did the Catalog description. This was as expected based on having 3 Parts Books that cover some number of years. The camshaft had light rust in some places on the bearing and cam surfaces. It is probably serviceable, but it proves the point that there is no magic about a company 27 years out of business. Need to oil and seal up this replacement cam shaft. The oil feed "O Ring" that they supplies appears to be the wrong size. 20-MAR-99 Based on the idea of replacing the cam bushings pull off the inner and outing timing covers. Things looked well oiled, relatively clean, and no water. The transmission was full of oil. The cam and lifters appeared well oiled. Now that it is all apart it looks like the ignition slop may have had more to do with the Lucas AA mechanism than with cam bushing slop. The screw plug in the back flow ball check valve in the inner timing cover appears to have been sealed with loctite. Have cleaned up the side covers and now: Final cleanup of outer cover 2nd stage cleanup of the inner cover Check the inner cover for: Oil Seal fit to CrankShaft Cam Bush slop Replace as necessary Final cleanup of the inner cover Cleanup of the Cam and Lifters Fix up a solution to the oil feed "O Ring" Reassembly and then oil engine and transmission This gets the engine sealed up again. Then fix up the Lucas AA and breaker plate 27-MAR-99 measure the up down and side to side play of the outer, i.e. timing side cam bearing on the BSA motor. It is between 2 and 3 mil and probably closer to 3 mil. This was done with shim stock, i.e. 2 mil fits and 3 mil does not. On the cam both shafts measure 0.748 with the outer end of the outer side shaft measuring perhaps 1/4 to 1/2 mil larger. As supplied the new Timing Cover side camshaft bushing had an ID of about 0.735 OK, tried boring out the bushing after pressing it in and something went wrong. It has a taper from about 0.744 to 0.753. OK will give up on this bushing and get a 2nd replacement. Got a 2nd replacement and it did not come in a "real" BSA factory sack like the first one. Also it does not look like its front thrust surface has ever been finished. Make some measurements to see about this. Original after 1st Replacement 2nd Replacement Removal after Removal before Installation ---------- --------------- ------------------- Lip 60 to 64.5 64 to 66 mil 71 to 73 mil Thickness mil Out Side 0.907" to 0.907" to 0.908" to Diameter 0.908" 0.908" 0.909" Lip Thickness 63.38 mil 65.44 mil 72.65 mil Measure it a Second Time The 1st Replacement was measured after it was removed. The 1st Replacement very clearly has had it thrust surface machined. So order of 72 mil - 65 mil = 7 mil needs to be removed or from second measurement 72.65 - 65.44 = 7.21 mil needs to be removed This will leave a lip that is about 2 mil thicker than what was on the original cam bushing. Ream the 2nd replacement to ID size using an adjustable reamer held in a tap handle. Did not run the adjustable reamer in the mill because the shaft on the adjustable reamer is bent. This reamer covers 23/32" to 25/32". The cuts were made as follows: 0.736" initial ID of bushing 0.740" after first cut 1/2 turn of adjustment 0.741" after 2nd cut 1/2 turn of adjustment 0.743" after 3rd cut 1/2 turn of adjustment 0.744" - 0.745" after 4th cut 1/2 turn of adjustment 0.746" - 0.747" after 5th cut 1/4 turn of adjustment 0.747" - 0.748" after 6th cut at this point the shaft starts to fit. 1/8 turn of adjustment 0.748" - 0.749" after 7th cut It fits. It is tight going in over the outer seal section and then turns freely over the section that ran on the bushing. The bushing MAY have a very slight taper with the outside part being tighter. Now cut 7 mill off of the thrust surface of the bushing. Because it was not possible to tell exactly when cutting started the mill table was raised only 5 mil after cutting was thought to have begun. Measure the Auto-Advance from the BSA motor. It is labeled as a 12 degree advance unit. The radius out to the stopping pins is 0.6375" and the amount of movement at this radius in 0.142" This works out to 12.79 degrees so yes the Lucas Auto-Advance Units are labeled in CamShaft Degrees. The radial slop between the center piece and the cam piece is 2 or 3 mils. It feels like more but clearly read on a dial indicator only 2 or 3 mils. The oil plug screw in the inner timing cover that holds in the spring and ball in the no leak through oil valve is about 0.375" outer diameter. It mostly measures 0.372" and is not tappered. It is 26 threads per inch. The threads are ??" deep. Note that the threads on the plug used on the C25 motor appear to be different than what is used on later B25 motors (based on the plug listed in the parts catalog for later B25's). The old oil feed "O" ring was reused when the cam shaft timing side bush was replaced in April 1999. It was not in very good shape. It appears to be different then the setup in the later B25 motors. The C25 does not have the center aluminum piece that fits into the center of the "O"ring. The replacement B25 "O"rings that I got clearly do not fit the C25 motor. The C25 "O"ring appears to be about 70 mils thick (after being flattened) 0.185" ID and 0.340" OD. (0.340" - 0.185") / 2 = 77.5 mil. 3/16 = 0.1875 5/16 = 0.312 5/64 = 0.0781 who knows ? Some dimensions for the CDI platform and battery mount. Step in Platform about 1" Width of Platform about 2 1/4" Battery tall 4 1/2" wide 3 1/2" deep 2 3/4" Battery Mounting Plate 1/8" thick Outside of Battery Mounting Plate to Oil Tank 6.15" Coil diameter 2.30" tall Box tall 4.70" tapper 0.075" on each side wide 3.70" 2.25" deep outside 13-June-99 Has been running fine with the CDI and new Timing side camshaft bushing. Checked with the strobe the pattern now looks very narrow. Because the new camshaft bushing with setup so tight I have directly feed oil to it perhaps 5 times (including before running the motor) by pulling out the AutoAdvance mechanism bolt and squirting oil into the center of the cam ad about the right depth. Changed oil before a ride to Stockbridge. Removed and washed out the tank but did not drop the sump. This was about the last weekend in May. Lost a screw in valve cover on the ride. Have installed the vented Primary Cover Clutch Adjustment screw plug and oil no longer appears to come from the alternator output wire grommet. Installed an oil pressure gauge. Basically 40 psi when cold and at speed, perhaps 20 or 25 psi at low idle when cold, very low (3 psi ?) at low idle when quite hot, ?? psi at speed when quite hot. May-2000 Replaced the kickstart return spring (which had broken late last fall). Replaced it with the version for the 1972 B50 which has a different part number than the springs for the B25, B44, (and early B50 ?). This new spring has 6 turns instead of the 5 turns of the earlier type return spring. It broke about 1/2" in front of the hook that crabs the kick start quadrant. This was the 2nd time that this spring has broken. While the quadrant was out I tried grinding a little off of the first tooth (which is normally ground down about 1/2 way). It now engages the kick started a little better. Next time it is out I may be worth while to grind it some more. Late Fall - 2000 Change fork oil, primary case oil, and engine oil including a full cleanout of the oil tank and feed line and sump. Need to install one spacer on the upper tank mount that was left out. It is on the tank. Early Spring 2002 From the outside edge of the spindal of the Auto-Advance mechanism that the ignition cam slides over to the center of the breather hole in the cam shaft (in the inner bore of the cam shaft) is 2.275". Late Fall - 2002 Change fork oil, primary case oil, transmission oil, and engine oil including a full cleanout of the oil tank and feed lines and sump. Did not put fork oil back in until spring 2003. Spring -2004 Install new battery Sealed 12 volt 5 ampere-hour Newark #:29C7223 Late Fall - 2004 Change fork oil, primary case oil, transmission oil, and engine oil including a full cleanout of the oil tank and feed lines and sump. 29-June-2006 Bike dies in GR on Fulton St. just West of the East Beltline. CD Ignition capacitor opened up. Use and external capacitor and ride it back on July 1st. June-2007 Change the oil in the engine, transmission, and primary chain case. Clean out the oil tank, oil lines, and engine sump. Use Castrol Syntec (part synthetic) 20W-50 in the engine. Use ?? in the Transmission. Oil the chain with 20W50. Clean up some of the wiring. There is a flaky connection on the negative terminal on the bike side of the battery connector. Review the wire on the ignition terminal block: Points: Red is the points moving contact Black is Ground at the points fixed contact Trigger cable to Ignition Box: Red to points Red, i.e. the signal Black to points Black, Ground Power from Battery: White -12V (recall Positive Ground) Black is Ground Power to Ignition Box: White is the -12V power Black is Ground Ignition Box to Coil: Red is the Coil + or Bat terminal Black is the Coil - or Dist terminal Ignition Terminal Block +-----+-----+-----+-----+ | * | * | * | * | | | | | | | | | | | * | * | * | * | +-----+-----+-----+-----+ | | | | ----+ | | +---- | | ----------+ +---------- August-2007 Changed the oil in the forks. I used 10W-30 in the forks. Now all oil systems have had their oil changed in summer 2007. The headlight bulb has a burned out filament. It blew out on a ride to GR. The bulb is a Lucas #446. May-2010 Changed the oil in the: engine, primary chain case, transmission, and forks. I took the oil tank and lines off the bike and cleaned them and blew them out with compressed air. 2 quarts of Castrol 20W-50 synthetic blend oil for the engine with the remainder just normal Castrol 20W-50. The transmission was filled with Valveoline 90W. The primary drive and forks were filled with 10W-30. When I drained things both forks had some clear water in what was drained out plus the oil that drained out was clearly tan colored and saturated with water. I do not know where the water came from because I do not think that it has been in the rain very much for a couple of years. I need to make a few more oil changes on the folks to get out the remainder of the water. The stop/tail light bulb is an 1157. \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\/////////////////////////////////////// A hint at the yellow tank paint: Try Dupli-Color DA1663 School Bus Yellow comes in 12oz spray cans. I found it at the local NAPA store. a possibly good epoxy paint is VHT self priming epoxy (SP-670 Gloss Black) from a spraycan. VHT Enamel (very high temperature ?) PJ1 spray can is another type. Sealed Wheel Bearings for twin leading shoe front wheel. Koyo 62042RSC3 bearings or Kaman #1640 DCT N. On line from WWW.kaman.com More Bearing part numbers: The 70-8003 bearing for crank on the B25 is Fafnir 305KDD A similar bearing is SKF6305 for $20 TRANSMISSION LEFT MAINSHAFT: #29-3857 or Hoffman 130 - Also sold as 57-0665. Local purchase was $9.30 as SKF6206/C3. This SKF number reflects a sealed bearing & will reduce leaks from the output shaft. TRANSMISSION RIGHT MAINSHAFT: 90-0011 or Hoffman L27 - Also sold as 04-0099. Local purchase cost was $15 as SKF RLS5. You can buy this bearing mail order for the same price using BSA numbers except you have to wait. TRANSMISSION LAYSHAFT: 40-3292 or Torrington B108. Also sold as 70-8005. Two are required. Local purchase was $3 each using the Torrington number. "On a 67 front and rear (wheel bearings) are the same so ..." "The bearing name is "NICE inch ball bearings" the number is 1640 DCTN" "Kaman bearings carries them http://www.kaman-ind-tech.com/ " "You'll need two tools. You'll need the fork oil seal removal tool." "AMR (Alternative Motorcycle Repair) in Arizona has them." "AMR part # AMR03272 " \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\/////////////////////////////////////// April 2011 Replace B25 rear wheel and bearings The rear tire is almost bald. It's size is: ?? While the rear wheel is pulled off the idea is to also replace the 3 bearings in it. The original bearings are Hoffman LS9 and LS9RS. I think that these are both: 7/8" bore, 2" O.D. and 9/16" thick. This is not a standard size for even an inch type bearing. The intent is to use an SKF RLS7-2RS1. The 2RS1 sufix indicates that this is a sealed bearing. I think that the bearings used in the standard B25 rear wheel are the same as used in the single leading shoe front wheel. SKF part number RLS7-2RS1 \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\/////////////////////////////////////// Final Drive Sprocket on the Transmission Output If the rear tier is going to be changed then it makes sense to at the same time: - Replace all 3 bearings in the rear wheel with new sealed ones. - Fully clean and then verify the the final drive chain is still OK. - Replace the final drive transmission output sprocket which is known to be rather hooked and could be the source of noise when running at speed. - How many teeth are on the sprocket that is currently on the transmission output ? Need to Check. - I think that the rear wheel on the B25 is currently 49 teeth. - The standard setups from the parts books are: 1967 C25: Primary Drive 23 ---> ? & B25: Final Drive 16 ---> 49 1969 B25: Primary Drive 23 ---> 52 Final Drive 16 ---> 49 1970 B44: Primary Drive 28 ---> ? Final Drive 17 ---> 49 1972 500: Primary Drive 28 ---> ? cc: Final Drive 14 ---> 52 Final Drive 15 ---> 47 Final Drive 17 ---> 47 - The relevant listed transmission output output sprockets in the parts books are: 1967 16 teeth 41-3095 1969 16 teeth 41-3095 1970 17 teeth 41-3092 1972 17 teeth 41-3092 \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\/////////////////////////////////////// 24-June-2012 Fill the primary case oil. Its level was OK. Oil clutch cable. Drain and fill both fork tubes. The oil that came out of drive side tube was clear, the correct color, and free of water. The oil that came out of the timing side tube was tan color, boardering on milky, but had no visible water drops in it. \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\/////////////////////////////////////// 17-May-2014 I got it out last weekend. The rust situation was quite bad I assume mostly because of the garage situation.