Hitchcocks Forum

I'm going to weld up the eyes on a pair of 350 flywheels that are badly flogged out and I was wondering if anybody knows how much interference would be required I was thinking 1.5 Any thoughts?

That sounds about right to me, Norm, although would it be easier to build up the ends of the crankpin by metal spraying to get a better fit and then hone the eyes in the flywheels to fit, as it might be less trouble than trying to build their surfaces up by welding and machining them out again? Just a thought, as I have never done this. Regards, Paul.

Thanks Paul, these wheels were damaged when the crank pin broke, I rebuilt that motor and it is back up and running but I used another pair of wheels. I need to repair this set but I have at least half a dozen other sets that are also flogged out so I have to come up with a fix.

Aren't 350 flywheels cast iron, and 500's steel?

Nope

Norm, what flywheels are they? Brit? Indian? pre/post 56?

Zippy, these are from a Super Star 350 Indian built probably mid seventies I think or that is what it is registered as. I think I found the reason for it breaking the crank pin, drive side wheel was out of round

Aha! yes, the indians have no concept of "Round"....
I have a pair of post 56 flywheels here, doing nowt, but I think theyre too broad for an indian motor :/

Zippy, I never really bothered to work out how it all goes together but some years ago I discovered that the English 350 flywheels weigh the same as the Indian 500 wheels but they are the same diameter as the Indian 350 wheels they are just wider. I haven't checked to see if they would fit in Indian cases

I Just thought it might be a useful labour saving shortcut,if they fit. But I dont know enough about the Indian motors...meanwhile, theyre not going anywhere...