Bsa B31 Compression Test

[@retromechanicalengineer]

Great to see a new video Brian, you have been missed. Best wishes, Dean.

[@500dbd34]

Hi Dean, thanks for the nice comment, more videos to come soon, love all your stuff, cheers Brian

[@UPTHETOWN]

Hope you're filming it Mr.A

[@500dbd34]

Andy, thanks for the comment, more stuff to come soon. Cheers B

[@davidclapham1066]

I'll test my C12 tomorrow and see what I get cold - thanks for the video Brian

[@500dbd34]

Thanks Dave, let us know the results of your test, not much data about on compression . I'm guessing anything above 100psi seems ok.

[@davidclapham1066]

​@@500dbd34 Mine had a re-bore, new piston and rings about 80 miles ago and I'm getting 125 PSI cold. I did read on a BSA forum somewhere that a fella's C12 seemed to run fine and he was only getting 80 PSI !

[@500dbd34]

@@davidclapham1066 Wow dave, 125 psi seems very good, you must have made a good job on the rebuild, I managed 120 ish on the electric start bike but not on the kick start. Thanks for the info, Cheers B

[@davidclapham1066]

@@500dbd34 Oh forgot to mention mine is a C12 but I think it's the same ratio as your B31

[@Cobra427Veight]

Hi Brian, I'm a new 54 BSA b33 owner , I thought mine was low on compression as it seems hard to find compression stroke , weird , so I just did mine and got 165 psi it has a triumph kick lever longer I think , it's got a m20 crank and big bore to make 597cc . Cheers

[@500dbd34]

Hi, your bike sounds great, well done for keeping our British bike heritage going. Cheers Brian