Hi

My -90 sc24 (71 000km)running poor at low speed (2000-4000rpm).. "She" has new spark plugs, valve clearance adjust, carb synchronisation is ok.. What I shouldchek/do next, any suggestion?

-topi

 

You´re probably looking at a carb cleaning job, but first, check that you don´t have any air leaks around the intake rubbers. Check by spraying start gas (aerosol) around the rubbers when the bike is running. An increase in idle speed will indicate air leak. My bike was running badly in that rpm range, and it turned out it was missing a rubber cap on one of the small tubes where the carb sync tool attaches, on the intake manifolds. I had my bike to a shop to check ignition, buying spark plugs, spark wires, spark plug caps (luckily not OEM Honda ones), and had the carbs off twice before I found that crap fault.

 

Oooohh, I better check that. (cough as high reves)
My bike has bugger all power below 3k, but I think that's by design.
3-6 is strong, 6is a power band, 9-10.5 is lost of license if caught.

 

Most CBR1000F's are low on power below 3000 revs - they are touring bikes, so not designed to run down at low revs. +1 on the leak check tho'

 

Thank you for your answers!

I must check outairleaks withthat "start gas"-spray, but like you say Mikekop, I am afraid, that carb cleaning job is head of me;-)