PD: Primary Drive Comet esa

vibrac

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Two up, luggage up stop in traffic or start on a slope or just the ease of starting as the years mount up. The question is Bill why wouldn't you?
 

greg brillus

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Hmmmmm......Without starting a hornets nest......I have just done a comprehensive rebuild of that lot in Tim's picture above.......This included replacing both sprockets, and doing away with the esa in the engine sprocket......I made up a simple cork washer bonded to the large washer on the gearbox mainshaft to slow the loss of primary oil out the hole. The biggest issue was the run out of both sprockets......The one on the Conways honda clutch had not less than 1 mm run out and this with another issue on the front sprocket was causing massive deflection of the primary chain........enough that it could be set to almost too tight, then rotate the engine a 1/4 turn and the chain would nearly fall off.........I'm not sure if it applies to all the Honda clutches but they do in fact have a cush drive built into them.......This is hidden behind the large wave shaped washer behind the unit........On the crank sprocket, the small yellow nolathane bushes seemed to suffer where the bushes were squeezing out between the side gap of the sprocket and the 2 hub parts, this was causing the sprocket to wobble a bit like a swash plate, this too was adding to the chain tension changing in tension.......We basically bought 2 new sprocket blanks and machined from scratch the 2 finished sprockets with near nill run out........We also had to fit a new center spline coupling in the clutch hub and re machine the spline on the gearbox main shaft, as this had suffered badly from excess wear on the spline.........With the discovery of the shock absorber in the clutch hub we decided to do away with the crank one, and made the new sprocket to be locked up, doing away with those small yellow bushes which were looking pretty second hand.........This bike had done less than 200 Km since the starter kit was fitted.......the issues with the clutch sprocket and spline existed way before all of this though.........Apart from that.....The starter seems to work very well..........Cheers......... Greg.
 

vibrac

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Well I am not going anywhere but I have a big work load but if I get a moment I will check out the primary alignment. I remember taking a long time to check the alignment and running it with the cover off and was happy when I put the cover on. That shock absorber in the Honda Clutch is a new one on me I have never noticed it.... I better check :eek:
 

greg brillus

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The cush drive in the Honda clutch is just an added bonus.......It looked to be in perfect condition, it was the sprocket that was the culprit........The spline in the center of the clutch was a big issue as well, the nut had not been tight enough and the whole lot was wobbling around quite badly........Luckily MartynG sent us a spare new one he had ( Thanks again Martyn) and we machined the mainshaft to suit, and made up a new flanged nut with a deeper hex so it could be tightened fully with no problems.
 

Bill Thomas

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I like a standard Bike Dave, As long as it's not mine :D
 

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