[Newbie with b12 carb troubles]

On 7/25/2020 at 6:50 PM, PaulSimmons said:

 

1200 mk1 bandit. 4900 miles. hi guys. I've just Ultrasonic cleaned the carbs and then fully rebuilt them wIth Keyster kits. IT now starts on the button just like when I bought it in 2000. But.... It will only run normal on 3 on tick over and low revs. On the other cylinder it pops and fires occasionally. On run down, out riding it pops and bangs. If I giVe it some revs say over 3000rpm  the problem cylinder kicks in.  Full beans and it's fine al the way up to the red line, pulls like a train . As the coils fire two cylinders I am puzzled. Could it be a dodgy hit lead? Or a dodgy Spark plug (already fitted iridium) ?  Or could it be the slow running jet? ( which one is this?) All jets were changed during rebuild. Could it be an air leak? could it be overfueling?

Any ideas very much appreciated, I'm near Gatwick?

check that you haven't pinched a slide rubber even a pin hole will cause a problem. easy to do as I have done it on mine when I had a b12. 

[750 36mm carbs on a 1052]

I'm going to use 36mm carbs off the 750 on my 1052 have a stage 3 kit for the 750 as I'm using twin k&ns and a 4-1 straight thru baffelled. was using 140 mains before.. does that seem big enough or should I go bigger just as a guide ?

thanks John