C15 beauty or beast

[DAVE BRADY]

Hi,

Recently purchased a '62 C15 for my wife as the '51 Flash is feeling a bit heavy after all these years of riding.
It looked ok in photos and so we went to have look.  The owner had had it for about 3 years and had done a cosmetic job but it still wore its original chrome with a patina that added to its attraction.
It started quite well and sounded great with no obvious engine noises or top end rattles.  After a few things to personalise it like handle bars, indicators, 12v, new carb. and it was ready for a ride.  I had a go and as it has been some years since riding a single, I though it was ok.  My wife had go and again after many years of riding a twin thought it was ok so we did a few runs and covered about 150 miles. The gear box was almost faultless and the clutch light and positive. So far a beauty?
The only niggle was the kickstart pawl was bit hit and miss so it had to be replaced.
Here enters the beast. Look at the photos to see what manifested itself as the depths were delved.
Worn clutch arm with the bit that engages the pushrod chewed and broken.
Pushrod end mangled and worn.
Pushrod in two pieces.
Whilst waiting for parts to arrive I though that I may as well check the primary chain which fortunately on this occasion having to take the cover off was worth what would otherwise be a pain.
So the first thing I noticed was the lack of a chain tensioner.  OK, so I happened to have one so easily remedied.
Taking hold of the clutch to check for wobble - like you do - I found quite bit and there was a lot of end float and rotational slop.
Next is to remove the pressure plate only to find the centre nut on back to front upon opening upon the centre hub absolutely no cush drive rubbers left.
On pulling out the main shaft it was evident that the end float was the result of worn splines that also show signs of over heating. The end float is such that none of the listed thrust washers are thick enough to do the job.
So far everything is fixable but the thrust washer is a challenge. I am currently trying to make a thin down a hard gearbox shim to fit behind the original thrust washer.

Why do we do it?

Dave.

[Rupert]

Hi Dave, the best solution I've found to the problem of an overthickness thrust washer being required on the mainshaft dur to worn splines is to use two spare thinner thrust washers from next to the spinner gears and surface grind them so that together they add up to the thickness required.
If you can measure the thickness required I can supply two washers to suit.

[DAVE BRADY]

Hi Rupert,

That is what I thought of trying. I have quite a selection of shin/thrust washer but no surface grinder. 
A technique I have used before is to use a magnet to hold the shim to ty to ensure even pressure and then use some 'wet n dry' on the the base of a pillar drill.
A few thou does take quite a lot of work though.

Dave.

[V500]

Early C15s didn't have a primary chain tensioner from new.
As for why we do it, it's so we can work on our old nails and fix all the PO's previous bodges.
Isn't it?

[DAVE BRADY]

Hi,

From the parts books it looks like the tensioner was fitted during '61 so this '62 should have one.
It beats me as to why there wasn't one from the off as on a primary with such close centres, correct chain tension is crucial.

On the shim/thrust washer front, I have reached the stage were I can turn the main quite easily by hand but will not do any more until I get a new gasket as the thickness will make quite a difference.

Dave.