Cam chain wear and damage

[adriangsmith]

I dismantled the top end of my 750 F2 engine today.
It was pretty obvious the PO had never tightened the cam chain.
Lots of rub marks and worn burred aluminium down the sides of the tunnel and all tensioners well and truly worn out.
The bit that concerns me though is the slot where the front tensioner locates into the crank cases as it has a lot of wear and has burred up into the joint between the crank case and the barrel.
So the question is can i use as is or should i attempt to repair the worn slot? if so what do people recommend to use?? or do i need to find a new set of crank cases?

[Bryanj]

This tends to happen when the rubber wears off the ears at the top.

What i have done in the past is make sure the joint surface is flat and check the fit of a new blade, normally a new blade fills the holes at the top and the bottom pin is only just a fit so there is no vertical movement. You could use some of the rubber off the old cushion in the bottom of the slot but not enough to mean you need to press the cylinders down to get the joint to fit.

This, of course, assumes you are using it as a road bike and not going racing!!