Inspecting rear drive shaft for water ingress

[spm0912]

All the recent posts on drive shafts seizing and peeps with water sloshing around the shaft has got me a bit paranoid.

I've commuted all winter and many of the roads were more like rivers, my bike is less than a year old with 14k on the clock. I plan to keep it for a while so really don't want to wait and find out if water is slowly rotting my FD

So is there an easy way of checking please?

 

[JohnnyBoxer]

So is there an easy way of checking please?

Take the boot off, between the swingarm and bevel box and poke around with a big stick

 

[spm0912]

How big does the stick have to be??

OK, to be more specific can you prise to boot off to look inside without having to remove the wheel and undo the trailing arm in order for the rear hub to pivot down? I don't want to start pulling at the boot and end up damaging it causing the very problem I'm trying to avoid!!!

 

[Pukmeister]

If I were that worried I would put it on the centre stand, remove the rear wheel, remove the rear ABS sensor then undo the paralever nut/bolt and unhinge the final drive to check, grease splines and change the final drive oil. About an hours work, minimal cost (oil about £15, grease about £5) and peace of mind once done with confidence gained in basic maintenance.

 

[B4ndit]

If I were that worried I would put it on the centre stand, remove the rear wheel, remove the rear ABS sensor then undo the paralever nut/bolt and unhinge the final drive to check, grease splines and change the final drive oil. About an hours work, minimal cost (oil about £15, grease about £5) and peace of mind once done with confidence gained in basic maintenance.

Just doing this job at the present time in the same order as pukmeister. I would add you need a new torque bolt for the paralever arm. You will need silicone grease for mating the rubber boot. I really don't know why BMW didn't put a drain hole in this area. Mine had lots of water in and I don't recall going through much deep water. It was grotty rusty water as well. All drying out for the night prior to reassembly tomorrow.

 

[spm0912]

Thanks, sounds like a job worth doing, surprised it's not been added to the maintenance schedule

 

[sidestand]

My GSA developed an ABS fault on the rear last November

Took it to my dealer, as it had happened before & sensor replaced under warranty.

This time, they had to change the final drive oil, as it had all gone milky with water ingress - had done 18000 miles at the time

 

[B4ndit]

My GSA developed an ABS fault on the rear last November

Took it to my dealer, as it had happened before & sensor replaced under warranty.

This time, they had to change the final drive oil, as it had all gone milky with water ingress - had done 18000 miles at the time

This is exactly what happened to me.

Now I have inspected it. I can see that the retaining nut on the bevel pin is rusty. As is the outer face of the bearing race. I wonder if water can get past this area and into the bearings around the bevel pin. There is one seal in this area and I am not sure if this is up to the job. Surely we can't have the only bikes to have got water in this area. And surely BMW can't have missed this sort of thing happening and not planned accordingly.

 

[Bendy toy]

A hole at the bottom of the swing arm will let water out.
Check out any bike that doesn't run an oil filled shaft tube they all have a drain hole.


Sent from my phone with mangled spelling

 

[Spout]

Thanks, sounds like a job worth doing, surprised it's not been added to the maintenance schedule

It was. All part of rear drive oil change.

Now of course, owners can change the rear drive oil without opening up the shaft drive.

I suspect we'll have a few UJ failures in the future. (UJs spinning around in water don't keep their grease for long)

 

[Pukmeister]

This is exactly what happened to me.

Now I have inspected it. I can see that the retaining nut on the bevel pin is rusty. As is the outer face of the bearing race. I wonder if water can get past this area and into the bearings around the bevel pin. There is one seal in this area and I am not sure if this is up to the job. Surely we can't have the only bikes to have got water in this area. And surely BMW can't have missed this sort of thing happening and not planned accordingly.

If you are talking about the needle roller bearing and trunnion sleeve on the final drive to swinging arm joint, then yes they do corrode and collapse. Mine did this due to water getting past the felt sealing washer, an easy fix and about £30 in parts. The handling felt odd until fixed, there was about half a millimetre of play in it.

 

[Steptoe]

I would add you need a new torque bolt for the paralever arm.

Really........ So every single bolt i've ever removed over the years (literally hundreds) and re-used weren't any good

 

[B4ndit]

Really........ So every single bolt i've ever removed over the years (literally hundreds) and re-used weren't any good

I meant the nut. Its some sort of a special nut. Thats what BMW told me. So at the cost of a nut its good enough for me.

 

[B4ndit]

Mine did this due to water getting past the felt sealing washer,

I couldn't quite work out what was behind the nut. Now you've answered that question for me. Everything is cleaned up now as best I can with that felt washer being like a strange item to work with. Thankfully no free play.

 

[Bendy toy]

Any play in the suspension linkage will feel like transmission backlash as the FD pushes down on power take-up.

 

[Greenman14]

A hole at the bottom of the swing arm will let water out.
Check out any bike that doesn't run an oil filled shaft tube they all have a drain hole.


Sent from my phone with mangled spelling

So, is the right place to drill a hole just in front of the FD pivot point?

 

[jmTIG]

OIL SPEC

READING UP ON THIS SERVICE , THERE SEEMS TO BE 2 OIL SPECs MENTIONED # CASTROL SYNTRAX LONGLIFE 75W 90 or 75W 140 ??

 

[B4ndit]

I used the 75W 90 stuff as recommended by BMW.

 

[GrinningGSer]

I opened up my 07 GSA in 2008, just to have a look:

Rusty as hell and never been fording (at that early stage) and no lubrication to the joint or splines whatsoever.
Very easy to do with good staged instructions on this site if you do a search. Get the Moly grease first and do it.
BUT having said that I'd say that unless you are a round world traveller, it is very unlikely that you will suffer shaft or joint failure
But and HOWEVER... I've just been to an evening talk by Pat Garrod and his wifel, who have travelled huge world miles on their GS and suffered MANY shaft failures (Not final drives which another thread).

 

[fatbaldbob]

If I were that worried I would put it on the centre stand, remove the rear wheel, remove the rear ABS sensor then undo the paralever nut/bolt and unhinge the final drive to check, grease splines and change the final drive oil. About an hours work, minimal cost (oil about £15, grease about £5) and peace of mind once done with confidence gained in basic maintenance.

Having the wheel off to change a tyre this week I noticed the cable for the ABS sensor was chaffing and almost worn through to the inner wire. I removed it to tape it up and adjust the routing of the cable, but on taking the sensor off I noticed the final drive oil was like milk. Taking the advice from above I thought now was a good time to sort it, I took the bike for a run to warm it up and drained the final drive oil, it was a light grey colour and almost as thin as water. I changed the oil and unhinged the final drive, to my surprise the splines were dryer than a dry thing from dry land on a dry day, yet there was loads of white grease on the inside of the rubber boot I guess to keep the water out, there was no sign of water ingress, so no concerns there, I greased up The splines and put it all back together, strangely enough the bike had an 18000 mile service less than 2000 miles ago by BMW, I guess they don't bother with these things. As per the post above its worth having a look for peace of mind.