Some of the weaknesses – afraid so, but then name a trouble free classic – & aspects of the bike’s design which warrant comment or modification.
Drive chain to the cam
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
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!
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).