nigelog

couldn't see any 21" rim, ta anyway

Front wheel chrome is rough on my C15 trials and I have been looking for alternatives, forks are B44 clamp type at bottom of fork leg did any japanese/ european manufacturers ever use a 40 spoke alloy rim in 21" that I could change to I can find a lot of alternatives in 36 hole, and have toyed with the idea of lacing the 40 hole drum to a 36 hole rim, but sourcing the odd length spokes may be a problem any pointers appreciated

holes drilled through primary side crankcase act as a weir keeping a level in the primary casing for the chain to pick up - the excess crosses back through the two holes into the lower crankcase and returns to the sump / oil feed pick as per normal - all this system does is reroutes it out to the prmary case and back in again so you are working off the one reservoir of oil. The primary case oil therefore is always topped up and always clean and filtered oil.

Hi Davetom I forgot to add that what was not mentioned by Rupert Ratio but I did (I spent so much time looking at the engine during rebuild the idea grew on me) - when you look down the crankcase mouth there is a ledge on both halves of the crankcase just below the barrel lip. On the timing side it is drilled to feed oil to the timing pinion bush. I drilled the primary side the same giving me a a feed that exits just above the primary gear and chain. I ran the engine yesterday with the primary case off as I wanted to check the clutch before replacing the cover and the spray of oil onto the chain and gear is better than I hoped for. I couldnt see the benefit of just leaving out the primary oil seal and hoping for the best. So my oil seal is in place and feed comes pressurised from the crank downstroke. I may have pictures somewhere - if I find i'll post bottom pic shows ledge on timing side - repeated for primary side to provide feed shown - no discernable ill effects

Davetom i did the weir type conversion on mine leaving the two ports tapped in case I needed to blank off again. I have experienced no problems with this method and have had less hassle with primary wear and clutch slip. Just do it as it says in the book

Hi Mcman I was unable to source them during my rebuild and being so small near impossible to measure. They are a tight fit and you possibly would get away with the old ones and a dab of silicone.

Hi mcman if what you are saying is that are the tube for the swingarm pivot and the lower frame cross support parellel to each other then yes they should look in line across the width of the bike- height wise I'll check later

Try talon gears they might go down to 15 teeth

Standard set up for the B40 would have been as mentioned earlier 52T clutchwheel- 23 front sprocket and 70 link duplex chain The trails dropped it to 52T - 18 and a 68 link duplex chain The b44/50 with more grunt went the other way and had 52T - 28 and a 72 link chain At the moment I am machining a compromise front sprocket of 26 teeth for road use as the 23 still low and limited. I think then I will be at the limits of the adjustment of the 72 link chain which fits the 28. As pat says with chain available for 20 or so it pays to replace it. I have a stator and rotor that look as if the chain snap at some stage broke either the crankpin or the gearshaft on the primary side.

Hi Charlie, heres a pic of the assembled pieces, interested by the "top hat" idea. Does mean more work on the outer though.

Charlie, needle roller definately the way to go. Worked out fine. Full story Http://rebuildbsac15.blogspot.com

Removed and sold elsewhere, price would have been interesting though

Hi all, Charlie I finally got my bearing from Alpha and they machined it (ground) to my tolerance which was good of them and very reasonable. I am sticking with my 23mm US bearing so as it matches the shim I made. I also got the 20mm bearing from Alpha to compare it so if you havent bought yours yet I'll swap it for a C15 metal clutch plate (I'm missing 1) and an Amal carb fibre spacer(mine is too small vertically and does not cover the seal all around). Re-assembly starting tomorrow. I also went with the crankcase breathing by drilling 2 x 3/8 holes but I tapped them so that if it does not work out I can block them without separating the crankcases. I also replicated the oil catch (used for the inner timing cam bearing) on the other side of the case to feed extra oil into the primary case. I'll see how I get on. Can be viewed at Http://rebuildbsac15.blogspot.com

Hi there all, West Cork is definately trials heaven but not many organised events as far as I can tell. Vinnie you'll have to get them nearer to us down here (keep me informed if u can). Bike was targeted to be finished Feb but a delay with a bearing set it back. I have it now and will start rebuild tomorrow. There is a good chance I will pre 65 trial it as I found I have a set of drive gears of the appropriate size which can be swapped over in a few hours. Looking forward to getting it finished.

Seasons greetings to you all and thanks for the assistance/advice over the last year. Rgds Nigel