Cylinder clearance

[(F5)]

All bores used to be iron. But cast over in manufacture. The old school repair was to bore out and fit a liner once the iron bore was too worn for reboring.

Even shrunk in the interface is not as good for heat transfer. But, hey, it kinda works and you are stuck with it if you cant get a new barrel.

Plating works well on ally. But needs special techniques to stick properly to iron. I guess many platers will have learnt these by now. Basically mask ally, acid etch the iron, and plate with far more current than you would with ally.

If they have done many barrels like this successfully (ask) then I'd take his recommendation to the letter.

[Noobi06]

Okey will do. Im just afraid that
1. Its going to run very hot and possibly heat pinch.
2. Im afraid that its going to decrease the lifetime of my pistons, and giving me large risk for seizing. He told me theres a chance the pistons might only last 50h, but with forged pistons it might be regular lifetime.

[SS109]

Wow, now that recommended large clearance makes sense to me. Personally, I would try to find another cylinder but I know those are tough to find. Go by what they're recommending and, like F5 said, follow everything to the letter!

[Zman]

The GG125 has a plated cylinder.

[(F5)]

Yes. He said that it has been sleeved by a previous owner.

[Noobi06]

Ok, so it was cheaper to sleeve the cylinder, so thats what some dumb owner did. On top of the sleeve, they put nikasil replating.
So I am going to replate that but of course the replating affects the temperature and lifetimes of the pistons.
I am going to run a clearance on 0.1 instead of 0.05 since these bikes are really common to heat pinch/seize when running even throttle on roads. A lot of people have driven 50kmh in traffic and from no where the bike stops.