I have just finished my Honda CB750 cafe project that i started last winter, but I'm having some issues with my carbs.
I bougth the bike as a non runner and the guy I bought it from said it was over 3 years since it last had run. So i have no idea how the carbs and engine ran before i took it apart.
So that was the history of the bike, now the engine has been overhauled and rebuild and I was ready to ride, but no.
Bike setup is as follows:
I have older type K2 carbs ( I think its the B750A model, I will double check..!)
Main jet - 115 (before new jets)
Slow jet - 40 (before new jets)
4 into 1 exhaust
Pod filter ( the are very old and two of them are in a pretty bad state - should I replace? )
All new Power arc ignition with new coil, cables and iridium spark plugs.
I had it running pretty good but it had some midrange problems, and it stops revving at 6500-7000 rpm. It sounded like it was running lean so i bought new jets from sigma6jetkit.com.
I pulled the carbs of and installed the jets ( they recommended 132.5 in cyl. 2-3 and 135 in 1-4 and 42 in the slow jets )
After I installed the jets the bike has been acting very weird. The nr. 2-3 cyl doesn't fire in idle (exhaust cool) and the plugs get very black.
I thought it had something to do with the ignition or plugs, but there was fine spark in all plugs and I double checked the timing.
After 4 hours of playing with this and getting nowhere I pulled the carbs of and put the old jets in. But surprisingly it ran just as bad.
So now i'm stuck on what to do...
Hope some of you have some good ideas....
all the best