Vintage Dirt Bike Q & A

Hi i have a 1980 cr 250 with a vintage iron power pipe and a DG silencer, A 1993 flatslide carb all so.
About 3 race meetings ago i had a full rebuild bearings, seals new piston an rings etc.
But now i have the engine all apart again! it started with what i thought was a little end noise so i went ahead to change it, but on stripping it down i found the piston rings outlet side was stuck in and a few like ribs in the chrome bore. and what appears to be play in the big end! I have always mixed the fuel correct so could it be the carb set up?
what jets would i need?
How would i know if its wrongly jetted?
Could anyone help me in the Birmingham area UK?
THANKS K

Your can try contacting Allens performance for your carb setup

http://www.allensperformance.co.uk/

Its unlikely your carb setup has caused any big end problem.
Is the big end play side to side or up and down ?? there is an allowable side to side tolerance.
On the rebuild was the big end bearing replaced ?
Sounds like the new rings where running to tight to start with.
I'd get the cylinder nikersiled instead of rechromed and fit a new piston and rings.

Hi thanks for reply sorry for the delay, No i didnt change the big end on rebuild, the barrel and crank is now at S E P Kegworth getting done,So hopefully shoud be ok for the next round.