Hi,
Has anyone converted the 350 into a 400cc, if so what parts did you use and was it worth it?
Many thanks...
yes i have you need a T140 piston and a standard b31 compression plate
Hi,
Thanks, is it a standard piston and what compression ratio?
Best wishes...
use the low compression T140 with shallow dome. In the Bonnie CR is about 7.5-1 however, it is a lot higher when fitted in the B31. I initially used a standard T140 piston and it pinked horribly, even with a decompression plate.
You can also modify the piston a little if you have a lathe. I can send you the details if you want to go that way.
I am currently running mine with a 5mm deco plate and it is very easy to start and runs well. I may try a thinner one next time the barrel is off for any reason.
I did fit goldstar type valve guides and GS touring cams which made it a bit livelier (and louder) but I'm back to standard now.
I think the conversion is worth it and it doesn't cost much, B31 barrels are not that costly.
have fun
Pete
Hi Pete,
Many thanks for the information, most helpful. If you could send me as much as you can I intend to go the 400ccmso I value peoples advice and help.
Thanks again...
sent you a PM ;)