Gearbox Gaiter Replacement (and rear disk while we are at it!)

adm1

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I thought I'd start a thread with pics on this so I can ask specific questions, and in case anyone finds it useful further down the line.....

So without further ado, the gearbox/swing arm gaiter on my 2011 R1200GS is cracked and needs replacing:

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Although it looks like this could be done without removing the swingarm, I'm going to take it all apart and check all the bearings etc... while I am at it. I also just like playing with spanners.

Bike up on centre stand, mudguard bits, exhaust silencer and rear wheel removed. Brake calliper removed and hung off the rear subframe. Speed sensor removed and hung out of the way.

First question....does anyone know the size/spec of the speed sensor o-ring? It looks a bit tatty and should get replaced.

Looking at the rear brake, there is plenty of meat on the brake pads, but the brake disk itself seems pretty worn. It's done 64K miles as of yesterday.

The spec says the rear brake disk starts out with 5mm and the service limit is 4.5mm. Micky Micrometer says it's 4.01mm. Oops. That had better get changed then. Presumably a new brake disk should get new pads at the same time as a matter of course?

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Best get a new one ordered up....

I''ve no need to rush this job as I am going to send the rear shock out to Denz0 for a full refurbishment.
 
Another quick question - before I order a disk, does anyone know if there is any difference between ABS and non-ABS parts? My bike has ABS.
 
I thought I'd start a thread with pics on this so I can ask specific questions, and in case anyone finds it useful further down the line.....

Subscribed and watching with interest :beerjug:

& yes, new pads with disc, always, I reused the bolts tho'
 
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Right, a bit more dismantling and I took the final drive off.

Fuck me the bolt that held that on was tight! Looks like it was put together with plenty of red Loctite. Still, a bit of heat, a big breaker bar and some swearing and I got it off.

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Then the shock came off to go off to Denz0 for rebuilding. And it looks like it was a good thing as well - I can see oil on the bottom of it, and I understand these things are prone to drop all their oil at inopportune moments. So that's good timing!

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Spoke with Luke (Denz0) on the phone about the choices for the shock and we will go with a slightly stiffer spring and also shim the internals to lower the bike a little. I'm looking at around 10-15mm lower being ideal for me. I can nearly but not quite flat foot the bike now, so just that little bit lower will be helpful. The old spring is a little rusty in places, so a new shiny one will be nice.

There didn't appear to be any free play in the drive line so far - so hopefully the bearings are all good and can just get repacked with grease and left in situ. I'll have a look later on.

Anyway....off to the Post Office to get the shock away.
 
The Disc has a thickness of 5mm when new, so BMWs 4.5mm tolerance is more for selling more discs than anything else.

I didn't replace mine until it was down to 3.1 and it was still fine. You just need to be looking for cracks around the discs especially around the holes.

If you do order a new disc, make sure to order the new disc bolts as well as they are a one time use only.
 
Keep the holes in the disc clear of all the shite you have in your disc and it'll last a lot longer without any wear grooves.
 
The Disc has a thickness of 5mm when new, so BMWs 4.5mm tolerance is more for selling more discs than anything else.

I didn't replace mine until it was down to 3.1 and it was still fine. You just need to be looking for cracks around the discs especially around the holes.

If you do order a new disc, make sure to order the new disc bolts as well as they are a one time use only.

I can't see any cracks, but I may as well change the disc while I have the bike apart. It'll give me peace of mind if nothing else. Will also replace the pads and use new bolts.
 
Keep the holes in the disc clear of all the shite you have in your disc and it'll last a lot longer without any wear grooves.

Indeed. There's a lot of shit in those holes, isn't there! Still, bike is new to me and I am basically going through it with a fine tooth comb.
 
Agree with others - discs can last way beyond service limit for normal road use if no cracks or distortion. If you replace, then use new pads too. I don't think there is a difference with abs vs non-abs rear discs, but you can look on real OEM as it does say for eg final drive where there is an abs and a non abs parts diagram.

For orings I tend to use BMW as they price to match places like motorworks. or just use eg motorworks. real oem gives part number

If you do any work eg disc with sensor out then prob worth putting something in the hole to stop dirt or grit getting in.

I forget if i mentionned previosuly but use the BMW gearbox gaiter. Motorworks one is a pattern part and died within a year when i used it. i then had to do job again with bmw one which is thicker and sturdier
 
Agree with others - discs can last way beyond service limit for normal road use if no cracks or distortion. If you replace, then use new pads too. I don't think there is a difference with abs vs non-abs rear discs, but you can look on real OEM as it does say for eg final drive where there is an abs and a non abs parts diagram.

For orings I tend to use BMW as they price to match places like motorworks. or just use eg motorworks. real oem gives part number

If you do any work eg disc with sensor out then prob worth putting something in the hole to stop dirt or grit getting in.

I forget if i mentionned previosuly but use the BMW gearbox gaiter. Motorworks one is a pattern part and died within a year when i used it. i then had to do job again with bmw one which is thicker and sturdier

Thanks Nic,

I already have a rag in the speed sensor hole!

I had forgotten about the realOEM site - but looking at it, it seems to show the o-ring is 15x2mm - part number 34527708523. I would imagine any standard decent quality 15x2mm o-ring will work though.

(I am just putting all the part numbers in here for my reference!)

As for the brake disk, there only seems to one version listed for both ABS and non-ABS Part number 34217664102. But it looks like I can pick up a new Brembo replacement disk wway, way cheaper than OEM (£73)
Disc bolts are M8X15,5-MK-ZNS3 - part number 33177709205

The replacement gaiter I already have - and it is indeed a BMW OEM one!

Onwards and upwards! Next stop trying to get the swing arm pivots out. Hopefully I can get the right hand one out without a slide hammer.

One more question....what is the preferred grease type for the driveshaft splines when I get it back together? I have a load of Silkolene Pro RG2 "Synthetic Racing Grease" - will that be suitable of should I go get something else?

And.....one more grease question....there was a white grease on the final drive gaiter. Any idea what that is?
 
That went much easier than I thought it would!

The pivot pins came out easily with no need for a slide hammer on the RHS.

I took the swingarm off and pulled the old boot off. It was definitely knackered.

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I popped the driveshaft off with a big screwdriver. No issue at all! I guess strictly there was no need to do this as I could have just slid the old boot off and new boot on, but I read it is worth greasing the driveshaft splines.

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Anyway, that's the teardown all done. Time for a cup of tea. Tomorrow I'll clean all the bits up as well as the back of the engine then do a good inspection of all bearings and see about putting it back together. I decided to bite the bullet on the brake while I have it all apart.
 
Some more questions while still fresh in my mind.

The three screws in the right hand side pivot are to secure the pivot pin into the frame. They are M6X16-8.8-ZNS3 - part number 07129904588

The central screw however appears to serve zero purpose - and on RealOEM it has no description or part number (I presume it just comes with the pivot pin). Is its' only purpose to fill in the central M6 screw hole, which itself is only there to allow a slide hammer to be attached to pull the pivot pin out?

The screws on mine are zinc coated and are tarnished. I presume these can simply be replaced with bog standard M6*16 stainless versions. And another for the central hole of M6 by about 10mm long?
 
Here's the REPROM picture of the pivot bolt extractor...
 

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moly grease for driveshaft splines. not sure what the white grease they use is. i refitted with a thick rubber-safe grease just to help prevent moisture ingress.

i don't htink you'll need to replace the pivot pin screws. just refit with some antiseize. central screw serves no real purpose other than to seal hole?

bike looks pretty clean. check ujs for tightness though, and check pinion for play before refitting
 
moly grease for driveshaft splines. not sure what the white grease they use is. i refitted with a thick rubber-safe grease just to help prevent moisture ingress.

i don't htink you'll need to replace the pivot pin screws. just refit with some antiseize. central screw serves no real purpose other than to seal hole?

bike looks pretty clean. check ujs for tightness though, and check pinion for play before refitting

When you say check the pinion shaft - I presume you mean the shaft sticking out of the gearbox? And if so, am I looking for side to side or end play - presumably either of those is bad....

On the pivot screws, £3.00 from Stig's Stainless and new ones are on the way - I just don't like the tatty look of the old screws and haven't got a plug for the cover. I'll probably replace most of the zinc screws on the bike with stainless over time anyway, so might as well start now!
 
Well done on getting all this done. You'll be well bonded within it one you're back on the road.

Mind how you go with those stainless bolts. The 'scruffy' OEM bolts are galvanised, hence they look scruffy. But actually they can be better than stainless - depending on what they're going into. I'd be inclined to use the OEM screws, with some copper slip or similar applied to them. If you don't like how they look, perhaps by a plug set?

Ref. the pinion shaft. I think that was reference to the pinion in the FD..

Sent from my SM-G975F using Tapatalk
 
i have a pivot pin cover on mine. looks neater.

play in fd pinion. check gearbox too but problems there are less common. gearbox output seal looks tip top

uj tight spots too - check this as common issue
 
When I last dropped my swingarm the taper roller bearings were starting to corrode - worth a check and replace or regrease. Laser tools sells a dedicated slotted socket with inner hex bit to preload and tighten the bearings for about £12.

If fitting a new rear disk its also worth checking the disk mounting hub flange is the newer steel one as per the recall campaign and not the older alloy one that is prone to cracking/failure.
 
And.....one more grease question....there was a white grease on the final drive gaiter. Any idea what that is?

Staburags NBU 30 PTM - about £20 for 50g.
 
So today I've done a bit of ordering of stuff, cleaning of stuff and general fucking around. Sadly the paying job wants some of my time and the wife and kids want to go to the pics tonight to see Joker...

So I've ordered up a new brake disk (Brembo), new pads (EBC Sintered), and new disk bolts, speed sensor o-ring and final drive breather from BMW. Also got some Moly grease for the splines.

Then I cleaned up all the pivot pins, bolts, drive shaft and swingarm. So looking for a bit of input on condition of aforesaid....

First off the driveshaft. The universal joints have zero play in them and no stiff spots. There's some small rust spots on the FD side, but it looks just fine to me. All the splines are in good condition.

Are the UJs meant to be lubricated in any way or are they considered sealed? I guess a little grease on them certainly won't hurt anything.

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Now the pivot pins. These look fine as well. There's some marking and wear marks, but the bike's done 64K miles.

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Right hand side one looks good as new

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Left hand side pin shows some minor marks

Anyway.... I think these are just fine.

I have a little more concern (but not much) over the pivots for the final drive. The sleeve has some witness marks on it (but they are very smooth) and the inside up the swingarm pivot also has some marks in one place:

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I presume these are actually all OK - but please shout if anyone thinks otherwise!

Then I checked the swingarm bearings and they both looked OK as well. I got rid of all the old grease to check the rollers and they are all present with no corrosion so I repacked the bearings with fresh grease and called that good.

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There is obviously a little side to side play in the bearings when not loaded - but again I presume the side torque put on them when reassembling the pivot pins takes care of that as they are (if I am not mistaken) tapered roller bearings and need side load to work properly?

And that's it for today. Tea or wine? Dammit, I have to drive to the cinema so it's tea....
 


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