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Technical section

Some of the weaknesses - afraid so, but then name a troublefree classic - & aspects of the bikes design which warrant comment or modification

 
Drive chain to the cam

 
ASA 35-1 is the spec - note no rollers For reasons best known to the designer he decided to use a rather weak little American Standard rollerless chain to drive the cam. Not so bad if the tensioners worked but they don't (for long). One function of a roller on a chain is to stop the inner side plates shuffling across the bush & self destructing in the cog teeth. This example came out of a 250 Wildcat engine - just in time. The chain can be found - quite cheaply if you buy 10 metres! Mail me for availability of smaller quantities.
 

Gearchange mechanism springs

 
Wears where the selector boss rubs.... The selector mechanism is under the same cover as the kickstart one & suffers from the same lubrication poverty. After a while running dry the hairpin spring wears through as the one on the left has. Its partner is a little U shaped number which returns the selector detents for the next gearchange. I've had a bunch of these made up (both types) & can supply them quite cheaply.
 

Kickstart mechanism - just about all of it!

 
Both faces wear but the circumferential teeth more so where they clash with the kickstart quadrant Another view of the sliding kickstart gear
Teeth snap off & the quadrant leading edge wears too

I could have taken pix of all the kickstart mechanism. It is rather under engineered, poorly supported & unlubricated (unless you attend to it regularly every 1000 miles or so - which you might but no one has for the previous 40 years)