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Separating Swing Arm and Gearbox - Necessary? (2004 R115R)

mikeseven

New member
I have an 04 R115R Rockster with 35k miles, in mint condition, no problems. As a winter project and before disaster strikes I decided to replace the clutch plate with the modified (longer spline) plate and lube the input shaft splines. I am most of the way into the disassembly process. I'm at the point where Mr Clymer tells me to remove the swing arm from the gearbox. I'm not sure I want to do this and I'm not sure whether it is necessary to do so. Why not just pull it all apart? Because (i) I'm lazy, (ii) I don't like pulling stuff apart that ain't broke, since I am prone to breaking things in the process. So, questions...
Can the gearbox and swingarm be removed as a unit? Pros and cons?
What's the experience with slave cylinders. Do they tend to fail in middle age? If they are prone to failure I might replace mine while I have everything apart even if it is not leaking.
I don't see any guidance in the factory manual or Clymer on the service interval for final drive splines. Now that the bike is in 1,000 pieces (thanks BMW) should I go the extra step and pull the final drive apart to lube the splines?
As always, advice and guidance much appreciated!
 
Both gearbox and FD can be removed together. I do it 50% of the time.
The only reason to disassemble is inspection or seal replacement.
Helps if you have a helper on the other side to support the weight and be careful to pull back straight so the pushrod does not get bent.
2 guide pins on the engine block help during the re&re

As far as the slave goes, be sure to lube the little bearing with wheel bearing grease, they are chronically undergreased from the factory.
Regular greasing (every 50-60k miles) has me on the original at 200k+ miles.
 

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There is no need to separate the swingarm from the tranny. I have removed a tranny even with the wheel attached. And with just the final drive attached. And with just the swingarm attached. I prefer the latter because of weight and balance issues. Otherwise it all wants to flop over to one side. But just the swingarm and driveshaft is no bit deal, and is the normal way I do it.
 
Related question...

How do you guys handle the battery tray? It needs to be raised to clear the rear battery tray mounts so the g'box slides straight back and if the the bike has ABS the ABS unit needs to be removed to get to the front battery tray mount nuts. Breaking the system is an obvious pain and a lot more work.

Other than prying (forcing) the back end up is there a work around that I dont know about?
 
Related question...

How do you guys handle the battery tray? It needs to be raised to clear the rear battery tray mounts so the g'box slides straight back and if the the bike has ABS the ABS unit needs to be removed to get to the front battery tray mount nuts. Breaking the system is an obvious pain and a lot more work.

Other than prying (forcing) the back end up is there a work around that I dont know about?

I have always removed the ABS unit - yes it is a pain. The bigger pain has been the hard brake lines connecting the ABS unit to the rear brake master cylinder and caliper. They have several bends and snake in place in one position only. On both my R1150R and Voni's R1100RS they must be removed before the rear subframe would pivot out of the way.

If there is a workaround I certainly want to know what it is.
 
What Paul said. I do the same.
I tried to do it in situ on a GS once, it is possible but the rear lines have to be gently bent and then back.
Not recommended.
 
The rear metal brake lines interference makes one wonder if Spiegler could make a flexible replacement for it. Would that make it any easier or not worth the effort due to routing/clearance issues.
 
Speaking of the rear metal lines...

I had just about finished lowering the tail and buttoning up everything on a recent spline lube when I realized that I had not placed the fuel distribution hoses between the two metal lines. The backtracking I had to do was painful.... grrrrrrr. Heads-up to Mikeseven.

Also Mikeseven - I have installed two of the Motorworks/BBY extended spline clutch plates and have noticed that the spline fitment is very precise. Starting the g'box output shaft splines into the clutch plate splines seems more difficult that with the OEM clutch plate, try it before installing the plate to see what I mean. On both occasions, despite the best alignment I could achieve while assembling the clutch pack, I had to install the slave cylinder and with the g'box bolts just barely started pull on the clutch handle to allow some movement of the plate. This allowed the g'box to seat properly to the engine. Something to keep in mind if you experience the same difficulty I did.
 
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I never remove the brake lines or the ABS unit. I remove the tray nuts under the battery, make sure the lines are free of the subframe, and then just raise the subframe. The back of the tray flexes upward enough to let the transmission out.
 
Related question...

How do you guys handle the battery tray? It needs to be raised to clear the rear battery tray mounts so the g'box slides straight back and if the the bike has ABS the ABS unit needs to be removed to get to the front battery tray mount nuts. Breaking the system is an obvious pain and a lot more work.

Other than prying (forcing) the back end up is there a work around that I dont know about?

I levered up the back of the battery box. It worked to get the gearbox out, which is just as well because if I had to remove the ABS unit I would be fixin to kill somebody. Let's see if everything goes back in the same way.. not feeling too optimistic about that.
 
Thanks for all the advice guys. I now have the gearbox out. The input shaft splines @ 35k miles look great to me (photo). The old Clutch disk splines look good too but of course I will replace with a new modified disk. The only issue I have seen so far is that there was a mess of oily gunk on the end of the clutch slave cylinder that pushes against the clutch release pushrod (photo). Is that normal? The slave cylinder itself does not appear to be leaking. IMG_3422.jpg
 
Thanks for all the advice guys. I now have the gearbox out. The input shaft splines @ 35k miles look great to me (photo). The old Clutch disk splines look good too but of course I will replace with a new modified disk. The only issue I have seen so far is that there was a mess of oily gunk on the end of the clutch slave cylinder that pushes against the clutch release pushrod (photo). Is that normal? The slave cylinder itself does not appear to be leaking. View attachment 65281

If the gunk is water soluble then it is brake fluid and bearing is failing. (the piston starts to spin in the bore scoring it) New slave needed.
When you get the new slave be sure to add grease to the bearing.
Picture below shows undergreasing.

Also wise to drill a hole in the bottom of the housing to allow fluid to escape instead of migrating along the pushrod and contaminating the clutch disc.
 

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Also wise to cut back the sheath to avoid rusting of the fitting. It fills with water from above and eventually rusts out the fitting.
https://imgur.com/cDgeNgN
<blockquote class="imgur-embed-pub" lang="en" data-id="cDgeNgN"><a href="//imgur.com/cDgeNgN">View post on imgur.com</a></blockquote><script async src="//s.imgur.com/min/embed.js" charset="utf-8"></script>
 
Thanks GS Addict... the top clutch line already shows corrosion, confirming your warning to trim back the plastic cover on the line to let moisture out.
Next question - what do you think of the state of the pressure plate and housing cover (photos below). They show some discoloration and some grooves. If these were brake disks I'd say "no problem" but I don't know how sensitive clutches are to imperfections and wear. Can/should these be resurfaced?
IMG_3440.jpgIMG_3441.jpg
 
I levered up the back of the battery box. It worked to get the gearbox out, which is just as well because if I had to remove the ABS unit I would be fixin to kill somebody. Let's see if everything goes back in the same way.. not feeling too optimistic about that.

If you have to wrestle with the back of that tray, the ground strap and are having difficulty with engaging the splines all at the same time you will definately be fixin to kill somebody.... probably yourself (grin).
 
Take a straightedge to the surfaces. Are they flat?
If not, putting in a new disc may cause slippage as full contact is not available.
If they are flat, take an orbital sander with 120 grit emery paper and rough up the surface before reusing

These ones cleaned up nicely last week
 

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Not being a professional mechanic working on the clock, I see nothing wrong for the enthusiast in taking each part off and cleaning / examining it as I go to confirm its condition. The gearbox is odd-shaped and heavy enough to wrangle with by itself and I have no "Soldier B" to call on for assistance. . In taking the drive end loose at 60K on my R1150 I was able to identify a notch developing in the front universal and a couple of pivot bearings that I didn't want going back in. I sent the final drive off to Anton for seals and he found and fixed another emerging issue I would not have known about. I'm not knowledgable enough to do component repairs. Then, when I got through, I knew and was satisfied with the condition of everything. Plus bits are easier to handle than sub-assemblies.

dis.jpg
 
I've raised the back of the tray enough for the studs to clear the holes but the ground lead required more than I was willing to pry. I'll give it another try next time.

Update: the motorcycle back together and survived a 50 mile test ride with no issues. While the bike was apart I replaced the entire clutch pack including the longer splined clutch friction plate, rebuilt the clutch slave cylinder, checked/adjusted valve clearances, replaced the alternator belt, replaced the spark plugs and did a full ABS servo system bleed. Total cost was around $450. The bike now feels just like it did before I pulled it apart, which I view as a positive sign. It was nice to see that, at 35k miles, all the innards were in great shape (including the original clutch and splines) and within spec. The only part that really needed repair was the clutch slave cylinder although it was working fine before hand.

Regarding the battery tray stud clearance issue discussed above, I did a mod so that I would not have to lever up the tray to clear the wiring harness should I need to pull the transmission again (I did not like bending everything out of the way - seems like it is asking for trouble). I removed the left rubber mount from the gearbox and replaced it with an M6 screw and a 1/4 inch steel sleeve cut to length - see photo below. Next time I will remove the screw from above and the sleeve will drop out of the way so the trans can move back without fouling the wiring. Installation was easy in reverse. If I had more time I would have worked out something with a rubber bushing instead of steel but steel should work.

IMG_3442.jpg
 
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