Gearbox output shaft failure?????

[redsoul]

Under advisement from Val H i undone the gaitor connecting the swing-arm to the bevel drive and about an large egg cup full of oil came out.I presume this is the output shaft seal gone.No oil drips on the floor when bike is standing and have checked all oil levels which are all ok.
This job is way beyond me but would like to know roughly how long the job would take by a mechanic and likely cost.
While its all apart what other components are worth checking/replacing.

 

[Kenny]

Wipe all clean and connect all back up. Use bike and enjoy...then check again in a month....if a lot more oil, then yes repair the seal...but if just a smidges....clean up, and enjoy bike Most of the para's chuck a little out ( I know they shouldn't )...but call it character and unless you are off round the world....don't lose any sleep over it

 

[(RIP) maverick]

Under advisement from Val H i undone the gaitor connecting the swing-arm to the bevel drive and about an large egg cup full of oil came out.I presume this is the output shaft seal gone.No oil drips on the floor when bike is standing and have checked all oil levels which are all ok.
This job is way beyond me but would like to know roughly how long the job would take by a mechanic and likely cost.
While its all apart what other components are worth checking/replacing.

Stand next to your bike and then start by working back from the swingarm to the gearbox part. (Below just a rough idea of things that needs to be done to get the gearbox out

Take off wheel
Undo the rear break assembly
Undo the shock
Undo the clutch cable
Undo the swingarm
Undo the shaft flange bolts

if it is only the seal you can now struggle to get the flange off the output shaft for a while

Replace seal and re-fit/torque all the stuff

If you an expert and know what you doing it will still take a couple of hours, not difficult but very time consuming. Depending on mileage etc you might want to get the gearbox bearings, selector spring replaced if it is coming out & check the wear on the clutch plate.

Check whether your bevel drive fills up with oil and start blowing it through the breather onto your rear tyre - if it has come to that time to definitely get it sorted

 

[Flipfly]

Bertha leaks in that department. I know why and she can stay as she is for now. It is apparently regular maintainence, with the older paras, to loosen the rear boot from time to time and clean it up in there.
Keep an eye on it, but Kenny seems to have the right idea, seems much more sensible whilst there is the possibilty of sunshine at some point soon

I like the old monos, there's none of this malarky

 

[redsoul]

Cheers guys..........As seems to be only a little oil at the mo and we still have sunshine i will wait untill the winter to get it done.
Bought this bike to learn to do my own maintenence and would love to try to do it myself but at the same time this is definately at the deep end for me lol.

 

[Beemerboff]

Generally seals last as long as the bearing they are sealing, so it is a good idea to plan on having someone go through the box in the foreseeable future.
Better to look at it as preventive maintenance than wait on real trouble.

 

[(RIP) pastyman]

As Flip says, Bertha has always leaked a bit, not as much as what you describe but I got a teaspoon full about every 1500 miles or so . Gearbox level was tropped up as required, not often. and the diff oil was never any different. I realised that I had not sealed up the little v vent in the output seal when I rebuilt the box and it could also be made worse when the earth strap bolt /vent got bocked. This created a build up of pressure in the gearbox which had to find its way out somehow.
My advice would be to keep yer eye on it and enjoy the bike, Sign up for the gentlemans weekend and ask the guys for help and get the job done . great for learning how to do it and a lot cheaper.

 

[bernardofeio]

"I realised that I had not sealed up the little v vent in the output seal when I rebuilt the box and it could also be made worse when the earth strap bolt /vent got bocked. This created a build up of pressure in the gearbox which had to find its way out somehow."

were the vent of the gear box? mine is also leaking....

 

[John Roberts]

were the vent of the gear box? mine is also leaking....

Here are some photos of the strap and vent bolt on my bike, it isn't a GS but I believe it is very similar.

 

[bernardofeio]

eheheh

mine has a normal M8 bolt insted....




thks

 

[John Roberts]

eheheh

mine has a normal M8 bolt insted....




thks

I could measure mine for you in the morning if you like, as you can see it shouldn't be too hard to modify a standard bolt. Let me know.

Or you could get a new one from Motor Works, see:
http://www.motorworks.co.uk/bmw/pro..._80&shnew=New&model=R45/50/60/65/75/80/90/100

See page 3:

Part SSA30599, £5.06 INC VAT
Please note that what it shows here is the part for my 1982 R100RS, I don't know which bike you have, it may be different to this one.