Great little kit but I've just popped the second piston due to the rings breaking up and pinking out through the exhaust. What causes them to break up? I might get another kit or get another rebore.
Running through a 20mm Dellorto and SIL Clubman. Carb main jet was slightly weak but the plug was still brownish.
I use semi synthetic at about 25/33 -1.
On points.
AF Kit Pistion Rings gone again
- scooterslag
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Ports too large causing the rings to snag and break?
The mack daddy on the left!
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Exhaust port to wide. Ditch it and get another you'll never stop it happening otherwise.
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A pal repeatedly broke rings because of his exhaust port being too wide. He did something like 6 pistons before finally admitting defeat and getting a different barrel.
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Who ported it? Go back to them and get them to stand the cost of a new barrel.
So I've stripped it down. As I thought, half the bottom ring went out through the exhaust port. You can see where the ring caught the top of the part of the exhaust port. It's a standard AF 175 kit. I'll take it in and see what they say. Maybe a thicker base gasket might work but I'll probably get another kit, more damn money.
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ring gap on assembly
He checked the ring gap in front of me last time. It's a shame as the kits can go well.