I've recently bought a 1990 CBR1000F. It's done 70,000 miles but the chassis is fine, it's all original and the motor is completely oil tight and pretty quiet. However, there's loads of vibration, tingling through the handlebars and tank, and getting worse with speed/revs. Pulling the clutch in at speed shows the chassis is smooth and free-rolling, so I don't suspect bearings or chains and sprockets. Rev it up in neutral/with the clutch in and the vibration is still there, perhaps indicating that it's not the gearbox.

Which leads me to the balance shaft. I've read elsewhere on here that you can adjust the balance shaft backlash to reduce vibration at the handlebars – loosen the locknut, turn the shaft back until resistance is felt, then back one increment and re-tighten the locknut. But mine never meets resistance, simply turning and turning and turning... which suggests the shaft has never been adjusted (because you can't adjust it) and is now so far out of balance it's causing vibration.

Faulty adjuster? Faulty spanner operator?

Any and all advice welcome, as I'm riding from central England to St Tropez in a few weeks!

 

those bikes did tend to vibrate quite a bit. Im not sure on the adjustment of the ballancing shaft though. I would also ask this question in the 1000F section on this board as well.

One thing to check though, is to make sure some did not remove the bar end weights. Im not sure if they can ever wear out, but it might be worth an inspection.

I would also check all of the engine mounts, and make sure you don't have any loose, or broken bolts.

I know, not really what your asking about, but something to check.