Bad vibrations
 

Hello All,

Presently in Georgia on my way across Asia onboard a 2003 1150 Adventure I am a little concerned at the intermittent vibrations coming from the bike.

The vibration is very noticable, but comes and goes and is more prevelant at high speed and during acceleration. It appears to be coming from the gearbox or the final drive but oil in both is fine and bearings are fine on the wheel.

I am riding on TKC 80 but niether those or an unbalnced wheel would cause a vibration that comes and goes.

To avoid a big back in the back waters of central Asia, does anyone have any ideas.

Nick Foulerton

Please visit Home | Foulerton.com to view our travels.

This may be no help at all but last year I had a severe periodic vibration that was unnoticable under about 50mph and bad enough to break the silencer mount over 75mph.

It came and went regularly over a 3 - 4 sec cycle. It turned out to be that both front and back wheels were out of balance (by quite a bit - unbalanced rim clamps) and the vibration from each was going in and out of phase cancelling each other out at some times and building up to a "super vibration" at others because the front and rear wheels were different sizes (21 front / 18 rear) and revolving at different rates.

The obvious fix was to balance both wheels and I've had no problem since.

Check driveshaft bearings, grinding noises/feel from driveshaft/rear diff area. A vibe like you describe is often the first warning of imminent driveshaft failure. Can also be the bearing system that supports the driveshaft - can't for the life of me think of the name at the moment - it's the ones in the black bungs at the back end of the driveshaft housing!

If you feel any bumps, roughness etc when you turn the wheel it's time to fix immediately.

good luck, and keep us posted!

This may not make sense to you, but check the engine crash guard and see if it has cracked somewhere.

Bad vibrations
 

Dear All,

Thank you very much for your replies and sorry about the poor English, the keys are all in the wrong place.

My gut feeling is that the bearings are on their way out in the driveshaft, however the wheel turns without grinding. Once I have more time on my visa in Uzbekistan I will replace the bearings.

Many thanks,

Nick Foulerton

Please visit Home | Foulerton.com - Times online 'website of the week' 10th September 2007.