Can you fit an 1150 GS Drive shaft on a GSA (2002 non ABS)

Mike F

Mike F

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Mine went pop...

Just picked up a GSA swingarm on eBay, but pukka GSA shafts are of course rare compared to GS. I believe I read somewhere the GSA are a tad longer, but equally that the GS works fine.

I'm sure a trawl round the forum would reveal some answers but I have to go to work and was hoping to try and buy the bits at lunchtime if I can so I can fit at w/e.

Also, while I have it all apart is there any useful maintenance to do? I am replacing the bush pins that hold the swing arm into the gearbox (if only because the shaft side one was obliterated in the mechanical carnage!). The rear hub seems OK, it spins freely and smoothly - but there are 2 roller bearings in the casing that I wondered if replacement was a good idea?

Its done about 120k miles, some hard miles too in the Big Bike Rally Challenge.

Any help appreciated.

IMAG1013
 
Alright Mike.

No idea about the difference in lengths but I doubt it's much. I've swapped shafts on my GSA and never had any issues. I guess it's only at full extension that any length would be necessary so people putting GSA suspension on a GS would have the same problem. I've certainly never heard anyone shouting 'help, my shaft has slipped out'... well... not on here anyway:)

And yep - I would change the rear needle bearings for the latest replacements from Motorworks, complete with grease nipples. Remember them?
 
Yes you can.

You will need a complete drive shaft, which you clearly need anyway. Because the difference between the two drive shafts is that there is a key spline on the adventure drive shaft where the stub shaft slides onto the main shaft. Where as the standard GS doesn't have the key. This is to enable setting up of the correct phasing of the shaft.

On the GS shaft you have to fiddle about to assemble, whereas With the adventure key spline, it only fits together at the correct phasing position.

The splines on the gearbox and the final drive, where the drive shaft sits between are identical on all 1150 models.
 
Ian J Hartley said:
Yes you can.

You will need a complete drive shaft, which you clearly need anyway. Because the difference between the two drive shafts is that there is a key spline on the adventure drive shaft where the stub shaft slides onto the main shaft. Where as the standard GS doesn't have the key. This is to enable setting up of the correct phasing of the shaft.

On the GS shaft you have to fiddle about to assemble, whereas With the adventure key spline, it only fits together at the correct phasing position.

The splines on the gearbox and the final drive, where the drive shaft sits between are identical on all 1150 models.
Click to expand...

My original 2002 GSA shaft wasn't keyed. I don't think all GSAs are.
 
Hmmm

Motorworks are saying the GS has 17 splines on the shaft and the GSA 16. So not interchangable.

Does having the "complete shaft" overcome that problem - I suspect it does. I removed the rear wheel drive as one complete unit which has a short splined shaft on it.

Then I removed what was left of what I called the drive shaft and have been shopping around for, so that was the splined shaft coming off the UJ that locates onto the drive shaft out of the back of the gearbox, the first UJ up by the gear box, the longer shaft coming off the UJ and going down to mate with the splined shaft coming off the rear wheel drive.

So is that the "complete shaft" - or would that mean the inclusion of the short splined shaft and knuckle that is in effect part of the rear drive assembly. If so a bugger to do I suspect.

Not back home until tomorrow when I can count my splines.

help appreciated....

So I am guessing this is not a "complete shaft"...

https://flic.kr/p/sg2Hbt
 
You picture is not the complete shaft.

You need both UJ's because the point where the two mate is the difference. Sure the standard GS has 17 evenly spaced splines where the two parts mesh together. The GSA has 16 splines, but one of the splines is double width and acts as the key so the phasing of the drive shaft is fixed.
 
Ian I appreciate your help. I'm guessing you are pretty intimate with the internal workings of a GS drive train!

So for an easy life I need to find the GSA part (as the rear wheel drive seems to be OK), but failing that there is a GS based route.

What a strange thing to differentiate between the two models.
 
Provided you get a complete drive shaft, which includes the UJ's at both ends you will be OK. The only difference is where the two halfs of the drive shaft mate together. Where they fit to either the final drive spline or the gearbox spine is identical on all 1150 models.

I would be wary about fitting parts from different drive shafts, only because a drive shaft is supposed to be spun up to speed and balanced as a complete unit to get rid of vibration. However, the short length of the GS shaft probably doesn't make that much of a difference.
 
I see from the Motorworks site, that though they mainly sell complete drive shafts reconditioned and used, they will also sell a used front shaft (as shown in your picture) and the rear shaft.

Clearly you need to count the splines on your rear shaft part still fitted to you final drive so that you will know what front half you will need.

When you look on eBay you often see just the front shaft displayed, this is mainly because the breakers haven't got much of a clue, and don't realise that the rear part of the shaft is only held in with a snap ring. They think it is part of the final drive.
 
Mike F said:
What a strange thing to differentiate between the two models.
Click to expand...

Phasing of the drive shaft is important to eliminate vibration. Without the key spline it is awkward to get the phasing spot on, you have to look up the tunnel at the position of the UJ and then orientate the UJ on the final drive to exactly the same position, then push home. Clearly with the key spline it will only fit at one position.

Phasing is where the UJ's at either end of the shaft are in the same plane. So if you had a ruler and ran it up the shaft it would run through the centre of both UJ.

I hoped that makes sense
 
reference the phaseing, if the UJ are out of phase, it will fall in to corners one way and be a pig to corner the other
sounds weird and I wouldn't have beleived it either - till it happened to me
 
BMW Max Fiche will give you the answer. It works for all questions like this: "Can I fit this part on this bike"
Find first the part number for R1150GS drive shaft, # 26 11 7 655 802
Then go to BMW Max Fiche main menu and Search. Then paste your part number in the box and you get all the bikes which are using this part.

Here are the bikes using that drive shaft

So, the answer is NO.

Pekka
:rolleyes::rolleyes::rolleyes:
 
I have run GSA suspension with HyperPro springs so high with GS driveshaft without issues....

As far as I know, the difference is by year not byGS/GSA the last 2 or 3 years having the solid spline (one slot missing).

So I got a 2004 front half, set it up and marked the lower with a marker the spline to come off...



Coverred the UJ and with a small stone in the Dremel... easier than expected...



And a perfect fit.. :beer:

 
If that is your shaft fully assembled, then it is 90 degrees out of phase.

Have you experienced any vibration and or other issues?

Edit
This article covers the earlier drive shafts R1100 to R1150, it briefly mentions the Adventure drive shaft, but it does show how a correctly phased drive shaft fully assembled should look.

http://www.largiader.com/articles/driveshaft/

:nenau

Ian
 
Ian J Hartley said:
If that is your shaft fully assembled, then it is 90 degrees out of phase.

Have you experienced any vibration and or other issues?

:nenau

Ian
Click to expand...

I cannot believe I did not see that, all very carefully done and completely wrong, only did it this week and have not had time to ride it.... too obvious to see :blast:blast

Oh well I have 2 other lowers in the cupboard... :D:D
 
Wow - dont you just love this forum. Fantastic advice.

As it is tho I now have a GSA 25k miles swing arm and the gearbox attached half shaft from a breakers for a very reasonable sum (£130 delivered).

Will be in the man cave cursing and tutting tomorrow as I try and put it all together...
 
Mike F said:
Wow - dont you just love this forum. Fantastic advice.

As it is tho I now have a GSA 25k miles swing arm and the gearbox attached half shaft from a breakers for a very reasonable sum (£130 delivered).

Will be in the man cave cursing and tutting tomorrow as I try and put it all together...
Click to expand...


OK, Stripped the lower shaft out fixed and re-assembled, all done.... :augie:augie
 
OK so my swing arm and top half drive shaft have arrived and I'm off to fit. There is a missing spline on the shaft coming out of the rear drive, but there is no corresponding key in the replacement half shaft.

I can copy the alignment from the busted one, but can be 180 deg out of phase when I do that. As my shafts weren't balanced as a pair I guess this does not matter.

Any comments welcomed,

M
 
Mike F said:
OK so my swing arm and top half drive shaft have arrived and I'm off to fit. There is a missing spline on the shaft coming out of the rear drive, but there is no corresponding key in the replacement half shaft.

I can copy the alignment from the busted one, but can be 180 deg out of phase when I do that. As my shafts weren't balanced as a pair I guess this does not matter.

Any comments welcomed,

M
Click to expand...

The 180 degree is not an issue, I can report that my "fixed" shaft is not giving any vibration..... pre the "solid spline" what you are doing was the norm..:beer:
 
Welshman said:
The 180 degree is not an issue, I can report that my "fixed" shaft is not giving any vibration..... pre the "solid spline" what you are doing was the norm..:beer:
Click to expand...

Yep, all done - and sweet as. Took her for a nice long test ride and all is good. Totally smooth. There was slop / snatch in the TX before it let go but all is good now.

Big shout out to Chris Matthews who is breaking a low mileage GSA twin spark right now if anyone needs anything. http://www.ebay.co.uk/sch/superbike...e=STRK:MEBIDX:IT&rt=nc&_trksid=p2047675.l2562

One word of advice on non keyed shafts, grind a little reference point (showing when knuckle vertical for example) on the rear drive end so once its all assembled in the swingarm its easier to align.

Great help as always on the forum, thanks guys.

Oh and I have a selection of off road wheels for sale if anyone wants them, incl a 21" front - and I am off to South Africa in July...
 
Nippy Normans supply Touratech, Wunderlich, Desert Fox and many other makes of accessories.
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