Bsa b40 piston Manuals For Triumph, BSA, Norton. Compression ratio does not really matter. 1963 - 1965. Turn the cngine until the piston is at the tol) of its sttoke, and resting both halJs rrll thc sidcs of the crank-case mouth, hold thc coflnccting rod bclwcel fiugers arrd thurnbs, and feet Ior up and down play. Also suitable for Triumph T140, TR7, TSS and TSX models. Fuel System. 00-3465-O Piston Ring Set, . We not only sell parts, but provide expert tech support! Contact Us with any questions you have. 25 mm. New bearings, sludge trap cleaned out, dizzy 'refurbished'. 4mm B44 piston 41-571 (std bore) B 00-3465-0 Genuine Hepolite Piston Ring Set, . 5mm TRIUMPH: 3T (350cc) 55mm 3TA (350cc) 58. 7 to 1 p The BSA B40 Star was a larger engined version of the C15 and was first produced during the 1961 model season continuing in production until the end of the 1967 season. A ‘NOS’ original Hepolite set of piston rings to suit the following BSA B40 – 350cc – 79mm std – 1961/65 Complete with instruction leaflets. A very high quality piston, rings and gudgeon pin. The motor came with a barrel and piston fitted. 4 IE: 76mm/25. Jan 19, 2012 · are the C15 and B40 barrels interchangable on the side points engine,if not I have heard of u=sing a Triumph 70mm piston,anyone know which one please. Supplied complete with Hepolite rings, gudgeon pins and circlips. Excellent Quality UK Supplied. 50cc 1965 piston ring Started by zak, 21 February, 2023, 18:36:07 Previous topic - Next topic May 17, 2008 · BSA B40 PISTON NEEDEDDoes anyone have a B40 Piston +040 and the rings and clips that they want to sell? I need one for my 63 BSA. THE HIGHEST COMPRESSION PISTON BSA MADE FOR THE B40 WAS 8. 5mm. 060″ (41-0250/41-0252/41-0254/41-0254-1) Review BSA Original Genuine Piston Rings . But the actual piston in the bx has 41-243 stamped on the top? None of the B40 parts books list a 41-0243. PISTON B40, +. 12mm or 45thou. Made in Italy OEM: 40-0630, 40-0632, 40-0634, 40 Jan 19, 2012 · are the C15 and B40 barrels interchangable on the side points engine,if not I have heard of u=sing a Triumph 70mm piston,anyone know which one please. 7 to 1 p CYLINDER BARREL, B40 ALUMINUM ALLOY WITH REPLACABLE IRON LINER 79MM - STANDARD BORE DESIGNED AND MADE FOR BSA UNIT SINGLES LLC. Standard Bore Sizes in Millimetres For Inches convert by dividing MM by 25. Please note, this is a Genuine Hepolite piston, NOT the New Hepolite brand which are made in Taiwan. Q1 what should the piston ring Martin:> - Recommended exhaust length and silencer type to keep engine quiet without strangling it? Charlie:> If we are talking BSA C15 B40, just look at the length of header pipe and silencer layout on the Scott Ellis bike and the Foster Otters. The bottom end is together with the correct non end "end float". THE CASTINGS AROUND THE CYLINDER BOLT HOLES WERE ENLARGED SO THE ENGINE BOLTS TRAVEL THROUGH SOLID ALUMINUM RATHER THEN BEING EXPOSED AS THE ORIGINAL CASTING IN IRON DID. Free Classic Motorcycle Parts Book Download. 00 41-0251 PISTON BSA B40 STD 8. 020 7:1 With rings, gudgeon pin & Circlips. 020 inches= . Find everything you need for your vintage BSA motorcycle including rods, crankshafts, frames, fenders and much more. 00-3463 Genuine BSA Piston Ring Set, Standard, BSA B40/B44 We have over 15,000 parts in stock! Please call us if you don’t see what you are looking for. We have listed parts here a number of BSA singles, including the C15 (above), B25, B40, B44 and B50 series. If you don't see what is is you are looking for, call or e-mail us. 040 10:1 COMPLETE FORGED HIGH QUALITY RACING PISTON MADE BY JE PISTONS FOR BSA UNIT SINGLES 2618 LOW-SILICONE ALLOY CAN RUN AT CLOSER TOLERANCES (. 7 to 1 p At this stage it is advisable to check thc big cnd bearing for rvear. 00 41-0255 PISTON BSA B40 1mm 8. 00 NOS BSA B40 SS90 +020 PISTON RINGS PIN 41-0244 Out of stock Add to wishlist Compare Oct 27, 2025 · However I've used BSA B40 pistons on both my Slopers. The piston, which is of the low compression variety, looks new and is marked as 1mm oversize and the barrel does measure 80mm. 00 Add to cart Quick View NOS BSA B40 Piston & Rings BSA part# 41-0079 Hepolite part# 15544 Size: +. 040, +. 1 NOS with rings In stock Add to cart Oct 10, 2012 · Can anyone help with an issue relating to B40 / B44 engine specifications? I have bought a B40 to convert for Trials. I've got my fingers crossed. FOR SALE! Genuine BSA NOS piston complete with pin, rings and circlips - 8:1 255120063073 B40 Piston20 February, 2025, 17:56:15 Home Search BSA Owners' Club Forum The BSA Workshop Singles B40 Piston Nice bsa b40 had a lot spent on it rebore piston elictron eng new back wheel and tyer is running but think it needs a carb I'll health Forse sale Oct 2, 2020 · You might notice pistons are slightly out of round and tapered near the crown. 7 to 1 p Hepolite Pistons for BSA A65 650cc UK Made With Piston Rings +20 Fits Models 1962-73 £120. It used the same 70 mm stroke as the C15 engine but the bore was increased from 67 mm to 79 mm to give a capacity of 343 cc. (40-0415) € 164,00 Read more Motorcycle Parts I bought a NOS STD B40 piston last year, part number 41-0242 was written on the box. Doing a web search and parts book search, this number 41-242 does come up as a STD B40 8. com Apr 30, 2010 · Anyone know if you can use a 350 B40 piston in a B44 to lower the compression ratio? Bore seems to be the same. Jan 23, 2025 · Genuine New Old Stock AE Hepolite Piston Complete with Rings, Gudgeon Pin & Circlips 79mm +20 at 7:1 Compression Please note, this is a Genuine Hepolite piston, NOT the New Hepolite brand which are made in Taiwan. BSA Unit Single spark timing degrees at full advance BTDC C15 33 ½ deg B40 33 ½ deg B44 round barrel 28 deg B44 square barrel 29 – 31 deg C25 & B25 37 deg B50 30 deg B50MX Getting your classic BSA motorcycle on the road is now made easy with our extensive parts range that we have to offer. BSA B40 Kolben +60 = 80. 020, +. ANOTHER UNIQUE FEATURE OF THESE PISTONS IS THAT THE DOME HEIGHT HAS BEEN SLIGHTLY DECREASED ON EACH OVERSIZE SO THE COMPRESSION RATIO REMAINS CONSTANT ACROSS ALL OVERSIZES. 010, BSA B40/B44 We have over 15,000 parts in stock! Please call us if you don’t see what you are looking for. BSA B40, 8:1 Compr. Orders ship same day. Default DescriptionA range of quality pistons suitable for a wide range of classic BSA motorcycles including the BSA C15, A10, A65, M20 and M21 models. Enquire About Our BSA Parts Motorcycle Pistons Please don't hesitate to get in touch, our team will aim to respond within 48 hours. The bike was always difficult to kick over, which maty explain this. 00 PISTON B40, +. 350cc. Quick links. 9mm) OEM: 66-0954, 66-954, 71-3185, 71-3700, 71-2970 Made in England Home / BSA B40 Piston assy cplt|std size|Partno. 5 MM COMPLETE SET OF THREE 3 BSA Sunbeam Piston STD With Rings NOS 76 158 +. Massive selection from top brands on eBay. Item ListPistons NEW BSA M20 M21 B31 B33 PISTON GUDGEON WRIST PIN 66-0953 $ 33. com. I've tracked down compression rings, old stock, but haven't found an oil scraper ring to fit; its +60 thou. 00. 020 7:1 With rings and gudgeon pin. 00 + $22. A SOLID ITEM. 0030) THAN OTHER B40 PISTONS ON THE MARKET BARE PISTON WEIGHT 343 GRAMS COMPLETE PISTON WITH RINGS, CLIPS AND WRIST PIN WEIGHT 448 GRAMS . Sharp short pipes and a resonator expansion box with a little silencing. There must be some somewhere. No circlips Gudgeon pin has some light rust Gudgeon pin has some light rust BSA B40 / B44 rockerbox complete with rockers|valve lifter etc. 1 NOS with rings In stock Add to cart Item description from the seller NOS genuine BSA B40 piston kit STD (41-0250) engraved 41-251 BSA P/N 41-0250 Thanks for watching We have tested BS As before; this time it is the B40, SS-90, Star Sportsman, which is a longish model designation for a machine that is basically very straightforward. 0030) THAN OTHER B50 PISTONS ON THE MARKET BARE PISTON WEIGHT 385 GRAMS COMPLETE PISTON WITH RINGS, CLIPS AND WRIST PIN WEIGHT 493 GRAMS . Bore Size : 75mm +060 OversizeCompression Ratio : 9-1Hepolite number : 19233OEM: 19233 Anyone know if you can use a 350 B40 piston in a B44 to lower the compression ratio? Bore seems to be the same. BSA B40 SS90 WD B40 PISTON RING SET +020" 79. BSA 343cc ( 350cc ) B40, SS90. Top quality BSA spares at affordable prices! I bought a NOS STD B40 piston last year, part number 41-0242 was written on the box. Great deals. 040 7:1 With rings, gudgeon pin & Circlips BSA Triumph Piston Gudgeon Pin Circlips - G Shaped With Tangs 2 x piston wrist pin circlips suitable for a wide range of BSA models including: A10, C12, A50, A65 + unit singles - B40, B44 and B50. 020 7:1 With rings, gudgeon pin & Circlips Anyone know if you can use a 350 B40 piston in a B44 to lower the compression ratio? Bore seems to be the same. Seems like its a common problem. Not all pistons are complete with box Suitable for BSA B40 1961 on Hepolite ref 15544 or BSA Part number 41-0077 A huge range of classic bike pistons made by Hepolite, Omega, Gandini and many more for Classic British Bikes like BSA, Triumph, Norton & Royal Enfield. ID: 3/4" (18. BSA B40 Piston +60 = 80. Get the best deals for Bsa B40 Piston at eBay. Manufactured by JP Pistons of Australia. (40-0415) € 164,00 Read more Motorcycle Parts BSA B40 Piston & Ring Set +20 Oversize OEM No 41-0077 Delivery & Returns Payment & Security View All BSA View All Pistons View All BSA Pistons SKU: PB40-080JE Quantity: Price: $225. 0027 TO . com Sep 26, 2013 · THE HIGHEST COMPRESSION PISTON BSA MADE FOR THE B40 WAS 8. POSITIVE EXPERIENCE. PISTON B50, +. NOS BSA B40 SS90 +020 PISTON RINGS PIN 41-0244 $ 220. 020 76 154 We would like to show you a description here but the site won’t allow us. 00-3464 Genuine BSA Piston Ring Set, . Find BSA B40 motorcycle spares and parts, including engine plates, pistons, barrels, exhaust systems, and more at Draganfly Motorcycles. Piston Clearence 0. A B40 piston uses a 3/4" gudgeon pin whereas an OHV Norton uses a 7/8" one. 75:1Suitable for the following models:BSA B40 SS90 models from 1963 to 1965 OEM: 16687 Manufactured by JP Pistons of Australia. Category: Engine, Pistons & Rings 41-0251 PISTON BSA B40 STD $ 295. I bought a NOS STD B40 piston last year, part number 41-0242 was written on the box. HEPOLITE PISTONS - BSAPair of Hepolite Pistons for BSA A65 650cc models etc (1962-73). 060, BSA B40/B44 We have over 15,000 parts in stock! Please call us if you don’t see what you are looking for. Found so far;- B44 Al. 95 GENUINE BSA B40 High Compression Piston - Standard size 41-243 - £10. A 16H side valve piston can be shortened and re-shaped to go as high as 9 to 1. BSA B40 GENUINE Piston STD (H) Complete & Boxed - Low Comp 8:1 - £135. A UNIQUE FEATURE OF THESE PISTONS IS THAT THE DOME HEIGHT HAS BEEN SLIGHTLY DECREASED If you own a BSA motorcycle and need new piston rings, it is recommended that you consider purchasing the BSA 41-251 NOS B40 piston rings with a size of 46/10-66 and an outside diameter of 79mm. Item ListPistons Description NOS BSA B40 Piston & Rings BSA part# 41-0077 Hepolite part# 15544 Size: +. Hastings, Hepolite, and Grant rings are one of the best quality items that you can install in your vintage BSA Hasting rings are made in the USA, Grant rings rings are made in Mexico and Hepolite rings are made in England (UK One JP Piston for BSA B50 500cc models etc (1971-). 7 to 1 p Shop Motorcycle Pistons, Rings & Piston Kits for BSA with eBay Guaranteed Fit. 040 Nos fits B40 The BSA 00-3423 B40 piston rings are a crucial component in the proper functioning of a BSA B40 engine. 040″/. BSA B40 Piston Std/Oversize . Take a look at our BSA classic bike parts. Supplied as 1 Piston, complete with JP rings, gudgeon pins and circlips. 060 8:1 COMPLETE FORGED HIGH QUALITY RACING PISTON MADE BY JE PISTONS FOR BSA UNIT SINGLES 2618 LOW-SILICONE ALLOY CAN RUN AT CLOSER TOLERANCES (. BSA B40 Scrambles Piston A BSA B40 scrambles piston has a high dome and large valve pockets so can be fitted to an OHV Norton to take the compression ratio all the way up to 10:1. The B40 has a standard bore of 79mm which means that +40 and +60 correspond to STD and +20 bore sizes on the Sloper. Bore Size : 84mm Standard, Genuine BSA A65 + 40" Hepolite Piston Kit, Hepolite Piston Kit 11062 STD - +20 - +40 - +60 To Fit BSA A10 650cc, Piston Ring Compressors 55 - 85mm, Hepolite piston kits +20 - +40 - +60 Triumph 750cc ,T150 and T160, BSA Rocket 3, Hepolite piston kit +20 - +40 - +60 BSA 650cc A65 for BSA Norton and Triumph Classic British Motorcycles. Please contact us if you can't find the BSA Piston you need. These piston rings are specifically designed to provide an effective seal between the piston and the cylinder wall, ensuring efficient combustion and optimal engine performance. Thanks, Bob California USA I bought a NOS STD B40 piston last year, part number 41-0242 was written on the box. Wheels & Parts. Aug 28, 2012 · Below is a list I have for setting points and positioning the AAU for various BSA unit singles. B40 motorcycle pdf manual download. 70-9104€68,00 Burton Bike Bits stock BSA spares for a large range of models. 4 =2. 00 41-0247 PISTON BSA B40 1mm oversize 8:7. Top Categories. Find many great new & used options and get the best deals for BSA Piston OHV NOS STD B40 Ss90 350 Star Original OEM 41-251 at the best online prices at eBay! Free delivery for many products! Piston Ring Clamp 75-80mm – BSA B40/B44/A65 Part Number : 61-3707 Rated 5. Parts included for BSA Bantam, BSA C15, BSA A10, BSA Goldstar, BSA Rocket, BSA B31, BSA B40, Lightning, Thunderbolt, and many more popular BSA UK made parts. 41-0250 Description Additional information €158,00 Add to basket Benelli 350RS - 354 luggage rack / grab rail€154,00 BSA A65 OIF Idler pinion|Partno. Apr 9, 2024 · BSA B44 engine with the cylinder head removed Do I fit a BSA B40 7-1 piston, and an 1/8" compression plate to bring the engine to perform more like a trials bike. Jan 17, 2008 · Help required. 0030) THAN OTHER B50 PISTONS ON THE MARKET BARE PISTON WEIGHT 389 GRAMS COMPLETE PISTON WITH RINGS, CLIPS AND WRIST PIN WEIGHT 497 GRAMS NOS BSA B40 Piston & Rings BSA part# 41-0077 Hepolite part# 15544 Size: +. 0030) THAN OTHER B40 PISTONS ON THE MARKET BARE PISTON WEIGHT 362 GRAMS COMPLETE PISTON WITH RINGS, CLIPS AND WRIST PIN WEIGHT 467 GRAMS . NO OTHER MANUFACTURERS DO THIS FOR BSA PISTONS. 060 oversize - please select. THE May 7, 2005 · Is it possible to enlarge a BSA Starfire/Triumph 250 engine to 350 or larger using B40/B44 parts, or are the two engines totally different? Martyn. We have a great online selection at the lowest prices with Fast & Free shipping on many items! 41-0251 PISTON BSA B40 STD We have over 15,000 parts in stock! Please call us if you don’t see what you are looking for. 020″/. We have a great online selection at the lowest prices with Fast & Free shipping on many items! Find many great new & used options and get the best deals for NOS- Vintage BSA B40 Piston w/Rings BSA 46/10-66 H 79mm at the best online prices at eBay! Free shipping for many products! 00-3463 Genuine Hepolite Piston Ring Set, Standard, BSA B40/B44 We have over 15,000 parts in stock! Please call us if you don’t see what you are looking for. BORE 78mm STD. 75:1. FOR SALE! This is the very hard to find genuine BSA high compression piston 375575138909 Feb 21, 2023 · BSA B40 3. 992 inches Oversize IE . There are however a couple of things that need changing in order to make it fit. 020 7:1 With gudgeon pin but missing the rings & circlips OEM PART No # 16687 #. In terms of cycle parts, the main difference was that the B40 used larger 18″ wheels front and rear 1961 BSA B40 specs, performance data, engine specifications, pictures. The engine has a high compression piston. Category: Engine, Pistons & Rings 41-0255 PISTON BSA B40 1mm $ 295. See what we stock on this list. This has been fitted with a BSA B40 scramble piston giving a compression ratio of 10 to 1. See what's new. ALUMINUM WILL GIVE FAR BETTER HEAT DISSIPATION THAN THE IRON CYLINDER DOES. View and Download BSA B40 technical handbook online. Quick postage at Classic Bike Parts Cheshire, all from trusted UK suppliers! Time to rebuild that top end on your trusty BSA? Consider using our quality Hastings, Grant, Hepolite and Taiwan piston rings to complete your top end rebuild. BSA B40 Piston Set Complete +40 Oversize. Hepolite ref 15544 or BSA Part number 41-0079. Gandini/GPM Piston - BSA C15 / BSA C25 - Circa 1959-67 Supplied as 1 piston, complete with rings, gudgeon pin and circlips 2x 1/16" Piston rings - 1st and 2nd 1x 1/8" Piston ring - oil scraper 1x Gudgeon pin - diameter: 11/16" (17. 25mm Oct 21, 2023 · Hi all, The saga of my B40 rebuild continues. 7 to 1 p I bought a NOS STD B40 piston last year, part number 41-0242 was written on the box. 7 to 1 p Shop Motorcycle Pistons, Rings & Piston Kits for BSA B44 with eBay Guaranteed Fit. 080 9:1 COMPLETE FORGED HIGH QUALITY RACING PISTON MADE BY JE PISTONS FOR BSA UNIT SINGLES 2618 LOW-SILICONE ALLOY CAN RUN AT CLOSER TOLERANCES (. THIS HIGHER COMPRESSION B40 PISTON IS ONLY AVAILABLE HERE. 4mm) 2x Circlips Bore Size: 2+5/8" (67mm) Standard, also available as +. Sep 9, 2025 · Suitable for BSA B40 SS90 models from 1963 to 1965. After stripping down my B40 i noticed the following. These OEM parts offer the advantage of being a direct fit and meeting the exact specifications and quality standards of the original equipment BSA B40 / B44 rockerbox complete with rockers|valve lifter etc. com Oct 2, 2020 · You might notice pistons are slightly out of round and tapered near the crown. THE HIGHEST COMPRESSION PISTON BSA MADE FOR THE B40 WAS 8. AS I AM MORE THAN HAPPY TO WORK WITH YOU TO ENSURE A. Discover the BSA B40-B44 piston ring set GPM Standard + Oversizes by BSA – ideal for restoring your vintage BSA motorcycle to its original condition. Kolbenbolzen Mitte bis Top: 41. PISTON & RINGS ONLY. 00 Mar 26, 2018 · Does anyone know of anywhere that stocks B40 piston rings? I bought a set of new Italian ones but they are too wide to fit in the bore once fitted to the piston. Suitable for BSA B40 1961 on. round Barrel marked 41-42 with a gasket face to face of 82. +40 = 80mm Piston Clearance 0. 00 shipping Aug 29, 2025 · Suitable for BSA B40 SS90 models from 1963 to 1965. Easily Find Vintage Bike Spares. 12mm or 45thou Gudgeon pin 19mm with Piston Rings, Gudgeon Pin and Circlips The purpose of BSA Unit Singles LLC is to provide enthusiasts of C15s, B40s, C25s, B25s,T25s, B44s and B50s with a single source supplier for parts and accessories for these models. ANOTHER UNIQUE FEATURE OF THESE PISTONS IS THAT THE DOME HEIGHT HAS BEEN SLIGHTLY May 20, 2025 · Find many great new & used options and get the best deals for NOS BSA B40 Piston Kit, Standard Size, # 41-0250 41-0251 8:1 Compression at the best online prices at eBay! Free shipping for many products! NOS BSA B40 Piston BSA part# 41-0077 Hepolite part# 15544 Size: +. Now to the top end. The B40 Engine has a B44 round Aluminium barrel with std bore. Shop Motorcycle Big Bore & Top End Kits for BSA with eBay Guaranteed Fit. BSA OHV PISTON NOS. 1 NOS with rings In stock Add to cart Mar 30, 2015 · I bought a NOS STD B40 piston last year, part number 41-0242 was written on the box. This is to account for expansion of material in the crown and that supports the wrist pin. We have helped thousands of customers complete BSA restoration projects helping preserve these historical classic motorcycles for generations to come. 00 out of 5 based on customer ratings (4 customer reviews) A typical example is the Norton engine above. Not all pistons are complete with box Suitable for BSA B40 1961 on Hepolite ref 15544 or BSA Part number 41-0077 Category: Engine, Pistons & Rings 41-0247 PISTON BSA B40 1mm oversize $ 300. Any advice on thichness of plate. A high quality piston, rings and gudgeon pin. Should there be a compression plate fitted ?, as the piston has touched the valves. It should be remembered that, even thouth there rnay be a little play present it will not necessarily rnean sudden I bought a NOS STD B40 piston last year, part number 41-0242 was written on the box. Middle Gudgeon Pin to top of piston: 41. mit Kolbenringen, Kolbenbolzen und Sicherungsringen. Size: 79mm +040Compression: 8. FOR SALE! Genuine BSA NOS piston complete with pin, rings and circlips - 8:1 255120063073 B40 Piston20 February, 2025, 17:56:15 Home Search BSA Owners' Club Forum The BSA Workshop Singles B40 Piston I bought a NOS STD B40 piston last year, part number 41-0242 was written on the box. 7 to 1 p PISTON B50, STD 10:1 COMPLETE FORGED HIGH QUALITY RACING PISTON MADE BY JE PISTONS FOR BSA UNIT SINGLES 2618 LOW-SILICONE ALLOY CAN RUN AT CLOSER TOLERANCES (. b40 accessories engine plates & tie bolts parts books air filter exhaust system petrol tank and fittings alternator fastenings, standard pistons and rings barrel etc footr Genuine New Old Stock AE Hepolite Piston Complete with Rings, Gudgeon Pin & Circlips 79mm +20 at 7:1 Compression Please note, this is a Genuine Hepolite piston, NOT the New Hepolite brand which are made in Taiwan. Item ListPistons Category: Engine, Pistons & Rings 00-3463 Piston Ring Set, Standard, BSA B40/B44 $ 45. 75:1 THIS WILL GIVE A BIT MORE POWER WITHOUT THE COMPLICATIONS OF EVEN HIGHER COMPESSION PISTONS I CAN ALSO PROVIDE 8:1 STD PISTONS MADE BY JE PISTONS FOR THE NIKASIL LINED ALLOY B40 CYLINDERS Jan 7, 2012 · Britbike forum Forums British Motorcycle specific Brands Bsa bulletin board Unit Twin Bore and Stroke Combinations Forums Calendar Active Threads , Posts: Joined: February 2007 Top Posters Jul 31, 2025 · NOS genuine BSA B40 piston kit STD (41-0250) engraved 41-251 $125. 25mm Shop Motorcycle Big Bore & Top End Kits for BSA with eBay Guaranteed Fit. lifcszd iic rywhgwvp jldx nsvpi hewpg zdgmm qbcz das soz fyaq wiaozyxr kqsemh shi owikao