Noisy Gearbox

[Ian Whinnett]

Last week I was changing the oil on my 1100GS G.Box when I had done I decided to run the bike in gear with the back wheel suspended off the ground. This was to circulate the oil and then re-check the level. (it was peeing with rain outside).

Whilst running the bike in gear it made some horrendous racket from the drive line somewhere. I did make it up to top gear and the faster the wheel the less the noise. The bike has always had a noisy second gear and I change the oil often and keep an eye on the amount of metal deposit on the magnetic sump plug. With a 45+ thousand hard miles I would expect some deposit on the plug and the oil comes clean after about 10 thousand miles.

I have checked the backlash from the back wheel with the bike in gear, there is some movement, but there is supposed to be some other wise the diff and g.box would seize up.

I am going to have to take the final drive off soom to do the pivot needle roller brearings. I suppose I ought to take the whole swing arm out and check the backlash directly into the g.box.

I am hoping it was just because the engine was cold and generally lurching around causing the noise.

Any ideas because the gears select OK and there is no noise on the road apart from the historic second gear.

 

[Kenny Rodkiss]

Most of the noise would be caused by the drive shaft rotating with more than normal angle on the joints because you had the bike on the stand which lets the back wheel drop.
If you drop the bike off the stand the swing arm will move up an inch or two and bring the shaft jounts more into line where they run much more smoothly.
Hope it makes sense

 

[Paul Young]

Ian,

They all do that under those circumstances & you're not the first to worry. It's not a problem, as Kenny described, but it does the UJ's no good at all being run at those extreme angles.

HTH,

 

[Vern]

Stiff noisy gearbox

Wear big boots and ear plugs. I haven't had a problem with my gearbox since I've been wearing these

 

[(RIP) maverick]

Running any GS on the main stand will produce a nasty noise which makes you run for the toolbox. They all do that. What you need to listen to is any whinning noise when you throttle down in high gears. My bearings whined louder than the engine noise which was a clear indication it should of been done long ago.
When you changed the oil was there small little metal flakes(1-2mm in size) in the oil? If so problem, if it was fine metal shavings normal wear usually.
The same goes for the rear bevel drive. Mine packed up shortly after my gearbox because I should of changed those bearings before I did the gearbox. Now besides for the irritating re-enage of the input shaft cams in 2nd and 5th gear all is ok an no more nasty noises(except when I run it on the main stand).

Hope this helps a bit before you strip the whole bike down.

Cheers

 

[Spanish Bob]

They all do that.

OH NO - Mav youve become institutionalised, you believe that!

 

[(RIP) maverick]

OH NO - Mav youve become institutionalised, you believe that!

Ahhhhhhhhhhhhhhhhhhhh Seriously my airhead also did the same as did some mates bike who I just checked to calm my shaky spanner hand

 

[Spanish Bob]

Ahhhhhhhhhhhhhhhhhhhh Seriously my airhead also did the same as did some mates bike who I just checked to calm my shaky spanner hand

OK I believe you, its just I only ever rode mine when it was moving

 

[Ian Whinnett]

Thanks peeps

Great, I don't know why I did not think about the excessive UJ angle. I should know being a mechanic, but then it is awful easy to convince your self that there is something wrong with your own machine. Being a mechanic does not make you heartless just cautious.

I am not that keen on working on my own machine but when I do I always take pride. So just those pivot bearings to do and then its all done.