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R100GS Spline Lube Discussion


Ron Miller, Manufacturing Engineer  < comments denoted>
Bob Pasker, Software & Communications Consultant ; original text

Charles Blair asked about instructions for a clutch spline lube on an R100GS. Here are the gen’l directions. Its not really hard, just a bit tedious. Thanks to Hesh for lending Bob item #2 below and some


1) clutch spline lube – $18 for 75ccs. it only takes 1cc so maybe someone you know has some.

2) a 27mm socket wrench that has had the outside diameter ground down so it will fit in the frame. forget about the special BMW tool – it sucks.

<many sockets work anyway. My Craftsman was ok as is.
Maybe 12 pt. is also thin-walled?>

3) get some grease suitible for your shifter pivot shaft

4) get a 23mm (i believe) spanner for the pure air system nut

< 19 or 17 mm to remove nut from hose connection. Socket
then goes over nut holding device to airbox. 22mm??
23 is not valid size choice. Big socket is cheaper and
easier to find than spanner. Crescent wrench would work
too but is tacky.>

5) some longer bolts – remove the lower right hand transmission bolt, take it to a bolt shop (yellow pages
under bolts or fasteners) and get 4 each of equivalent threads 4″, 5″ & 6″ long bolts + nuts. Cost will be about 35cents/bolt – just get the extras so you’ll have them on hand.

< Or just ask for: M8 x 1.25 mm/turn  x whatever length you want>

6) get the lock-tite which comes in a red bottle but is actually blue colored inside.

< Loc-Tite 273 if you want to use it>

7) the HAYNES manual

8) a metric Allen bit to match the swingarm pivot pin hole size. This will be required in order to retorque the pivot bearings with a proper torque wrench.

9) Calipers or functional equivalent to measure equal distance between frame and swingarm on each side.

10) Torque wrenche: suitable for 80 ft-lb (pivot locknuts) suitable for 8 ft-lb (pivots)


0) Disconnect the battery ground. Just in case of a pinched wire later.

1) remove gas tank

<don’t forget that annoying cross-bar. 10mm bolts. 1/4″ deepwell
socket works well. Also notice tubing connected underneath left
side. Handling the tank is easier if you drain it into a gas can
before wrestling it off the bike. Alternatively, ride it down to
reserve or beyond prior to maintenance.>

2) remove seat + storage bin under seat

3) drain & replace the float bowls & detach the carbs from the air box & cylinder heads. bungee them together using a long cord around the front of the bike so they stay out of the way.  take a sheet of newspaper and stuff it into the intake holes now open at the rear of the heads. LEAVE A LOT

< I use toilet paper for this. Length as desired.>

4) disconnect the pure air system from the cylinder heads (long silver 3/4″ or so diameter pipes from the front of the cylinder heads to the air box)

< I just disconnected them at the airbox and let them hang.>

5) take the air box top & filter off; disassemble all the little pieces inside, but just enough so that you can remove them. the huge  silver tubes which go to the carbs twist out.

<gently pry them away from the airbox from the outside>

The large nut holding the canisters in place require a wrench size that is not in the tool kit.  the rest of the stuff just pulls apart. this step took me about 45 minutes because its not exactly intuiative as to how to do it. just be careful and be sure to disconnnect all the little bitty vacuum hoses that are at the front of the air box.

< helps to loosen the black engine cover forward of the
airbox to get access to the various hoses.
I removed the RH air valve and both black rubber air
horns. There are 3 connectors going forward to hoses
under the black engine cover. All are grommeted or sealed
in some way so the airbox doesn’t suck dirt on the clean
side of the filter.>

6) remove the bottom of the air box. there are two allen bolts at the top facing fowards of the bike which also hold the tranny to the engine case and another bolt going downwards into the tranny.

7) with the bottom of the airbox removed, replace the bolts with longer ones and screw them in about 1/2 inch

< the transmission will be suspended from these bolts when
it is slid back>

8) remove the rear wheel; use a rope or a tie down to hold the swingarm up. the rope should go around the drive shaft (not the small torque bar under it) up and over the top of the frame where the seat once was.

9) remove the swingarm pivot bearings lock-nuts. these are VERY difficult to get off – they take about 80 ft-lbs of torque and are lock-tite secured.

< easier if dealer did the first spline lube job. Use rag to
clean between swingarm and frame before removing pivots.>

10a) remove the swingarm pivot bolts – these take an allen key and are what are held in place by the swingarm pivot bearing lock-nuts. be careful with them. remember which goes on which side so that you can recenter the swingarm in the frame at the same place.

10b) remove the top lock nut from the rear shock absorber and bolt. at this point, there is very little holding the drive train in place so be very careful.  the drive train should remain in place and the rear part of it held up by the rope/tiedown over the top of the frame.  you might want to put a jack or
something underneath the rear end, just in case. With the rear tire removed, the rear is much lighter than the front so I personally did not do this. YMMV.

11) remove the clutch cable nib from the rear of the transmission and secure it out of the way

< loosening adjuster at handlebars and levering the actuator
arm will let you free the cable end from the frame and then
remove the cable end. I also removed the actuating lever
from the tranny since it would hinder rearward movement of
the tranny.>

12) remove the allen screw which is the pivot point of the shift lever – be sure to watch the little rubber washers which go on either side. its greasy, so store it in a safe place so it don’t get dirty.

13) remove the shift lever from the linkage by loosening the top lock nut on the linkage rod and rotating the entire shift lever off. notice the place where it was screwed in at so you can put it back to the same place.

< I didn’t need to do this. I just weaseled the thing around out
of the way.>

14) remove the bottom two tranny bolts. the one on the left is hard to get to – just take your time. the right one is kept in place by a nut rather than being screwed directly into the main engine case. replace these bolts with ones of larger size. the bottom right tranny bolt wants to be inserted “backwards”: put the bolt where the nut goes and put the nut in at the back; otherwise you cannot get the bolt top past the ribs in the transmission.  don’t tighten these bolts – just screw them in a ways.

< I couldn’t get the LH one in. >

III. doing the lubing

the transmission should slide back a couple of inches along the longer bolts with no problem, exposing the entire clutch spline in between tranny/clutch and engine case housing.  using a fine brush, place a
little bit of lube around the spline. do not apply much lube because centrifugal force (or inertia if you prefer) will move the excess from the spline onto the clutch – not a good idea.

NOTE: For lube tasks beyond the first one or two, it would be an
extraordinarily good idea to clean the old lube, along with the
clutch material in it, off the splines. Carb cleaner and a toothbrush
should work.

IV. reassemble the bike 🙂

I dipped all the dirty metal parts in a kerosene cleaningsolution (sold in auto parts stores) and dried them off with lintless cloths before replacing.

Torque all the bolts to what they should be.  For items whichvcould not be torqued because of their unusual positioning, I used the appropriate tool (i.e. what ever would fit) and approximated based on the feel of the bolt.   For anything that was critical (swingarm pivot bolt lock nuts, the 4 tranny bolts, rear shock top bolt, etc.) I used lock-tite before reinstalling.

< For an opposing point of view, I used anti-seize compound
on the tranny bolts since I’ll have to do this again sometime.
If  my transmission falls out at 105, you’ll know what happened!
The only place I locktited was the clutch lever pivot bolt.>

When putting the swingarm pivot bolts back in, raise the
swing arm and screw in the bolts to about where they were,
putting the left bolt back in to the left side and right to
right side.

<Be careful to center the swingarm when bringing up the pre-load
on the pivot bearings. Any leftover green paint from the QA checks
at the factory can be helpful but should not be the sole

and most of all, have fun.

– bob

< Took me 4 hrs the first time. I too, lost time reassembling the
damn airbox! I could probably do it in 2 hrs or less now.>

The new bikes also are supposed to get their drive shaft splines
lubed at 40kmiles. I’m sure this applies to all. Have to remove
bevel drive to do. Bitch of a procedure. Also supposed to
lube ignition advance mechanism at 40k. Probably not so hard.
It even looks like the bevel drive pivots have changed material
since new ones are black. A hint, perhaps?>

First person to disassemble the bevel drive owes us a report!
===> NOTE: I went ahead and did it. Separate report available.

From: ron miller <>
Subject: Gear case splines too

Originally written Nov. 1992.
Edited Nov 1993

May also apply to R100R. This is an item peculiar to Para-Lever rear suspensions.

Mechanic’s Note:

This procedure was carried out on a 1988 R100GS with no saddlebags.
The bike has 16,000 miles including many serious gravel roads.
The purpose of this was to ensure good spline lube since my suspension gets more than average workout per mile. This is supposedly a 40,000 mile maintenance item. I did it early. So sue me.

Consider carrying this out in conjunction with doing the clutch spline lube job. You have to remove a bunch of common parts to do either job. Make a big afternoon of it. May as well……

CAUTION!!! My lawyer advises me to tell you that you should never even
consider doing this. You might hurt yourself. Sell your bike
to avoid temptation. Sell it now, while you still can.

Time Required: Your guess is better than mine.
(The first run thru this took me about 2.75 hrs. This
included figuring out what brushes to clean with and
40 minutes fiddling with the splined parts on reassembly.)

Tools & Material Required:

* Staburags grease (same stuff as for clutch spline lube)
=> Staburags has been superceded by other stuff. The newer stuff is
supposed to be better at preventing corrosion. My suggestion is to
use the new stuff where all the old can be cleaned off. Where
the old Staburags remains, use more of it. Almost any GS-head
probably has 5 lifetime’s supply of Staburags if you need some.
* anti-seize paste (Never Seez or whatever)
* 27 mm socket
* 17 mm sockets & wrenches
* assorted other wrenches & sockets
* 12mm Allen bit (you may have to go to Snap-On or Mac to get)
($ 16 from Mr. Mac)
* 6 mm Allen bit
* Long wrench handle to fit the 12 mm bit.
* Pipe extender for the wrench handle (optional; I didn’t need it)
* Torque wrenches – 100 ft-lb  and 10 ft-lb ranges
* wood blocks, scissors jack(large stable landing area), tie-down strap
* Loctite 273 (red bottle, blue juice)
* clean lint-free rags
* small toothbrush-sized wire brush
* used nylon toothbrush that you’ll never use in your mouth again

Precautionary material that would be nice to have on-hand, just in case:

* One (or two?)  pivot bearing (33 17 1 452 672 “needle sleeve”; $30)
This pn changed to 33-17-2-311-091 when the bearing became a
semi-sealed type. The new one will not drop its races on
disassembly. (if you can replace it without screwing up the seals)
Replacement  requires access to a Kukko internal bearing puller
and an industrial-strength heat gun. (Heat the swingarm really
hot and then pull the bearing. Heat to reinstall new bearing.)

* New, steel inboard pivot pin (33 17 1 310 890; $30). Use only
if your bike has the shiny aluminum pivot pin. This is the
black, steel one used on the newer bikes. The black pin has a
post (that fits into the inner race) twice the length of the
earlier design.

* New dust boot.


* Bike is clean. Pay special attention to the pivot pin and locknut on the outboard side of the swingarm.
* Bike should be cold (don’t need to add muffler burns to the expected casualties)
* Mechanic is in a good mood and ready to be patient.
* Strong helper  available to help steady the bike during severe torque application. (optional?)



1. Position bike on centerstand where rear gearcase and swingarm is accessible  from both sides.
2. Remove seat, tool box,  R side panel. Set aside.
3. Remove rear wheel. Set aside
4. Drain gear oil from the rear drive if desired. This will let you set it down as desired.
(I recommend putting some duct tape across the fill plug to remind you to refill it.)
5. Secure tie-down strap around frame to support the swingarm forward of the rear drive joint. Pad frame to prevent paint damage. Do not strap under the torque arm.
6. Position scissors jack so as to be correct to support the rear gear case when shock and torque arm are disconnected.
7. Remove rear brake cable from brake actuating arm. (the wingnut, pin and rubber boot must be removed)
8. Remove the black plastic cover from the outboard pivot bolt. Set aside.


1. Crack loose the outboard pivot bolt locknut. (do it now while the shock and torque arm hold everything steady)
2. Crack loose the inboard pivot with the 12 mm Allen key. Unthread about 1/4″.  (Both Haynes and Clymer report that a 3 foot breaker bar was required due to Loc Tite on the threads. Mine only required the 24″ bar for 1/2″ sockets, and less than super-human strength)
3. Disconnect shock bolt (2 17 mm wrenches) at top of shock. Keep washers
and spacers in order.
4. Disconnect shock from stud on gearcase. 17 mm (may have to wiggle shock and/or lower the rear gear case to get clearance) Replace washers and nut for safekeeping.
5. Unbolt torque arm. (17 mm and one smaller) Set parts aside.
6. Remove the dust boot clamps from the joint boot. Set aside.
7. Peel the boot down the swingarm and onto the gearcase. Be careful  with this unless you have another one handy.

8. When the rear gearcase is unconnected to anything except the swingarm at the pivot bearings and is resting on the scissors jack, you are ready to risk everything and get into trouble.

============= POINT OF NO RETURN =================

** Be especially careful to not put greasy hands on the exposed brake shoes at
any time. Also note that brake dust isn’t very good for greasy parts.

9. Check that the floor under the joint is padded with a clean drop cloth to catch stray pivot bearing races.

10. Back out outboard pivot pin ( 6 mm Allen)

11. Back out the inboard pivot. It’ll probably feel gritty rather than smooth. This is loctite messing up your swingarm threads.

12. Carefully support the gear case as you remove both pivot pins.
13. Set the pins aside with room to add the bearing races when they  come out.

14. Slowly lower the scissors jack a little ways to allow the gear case to  extend away from the swingarm. Guide the brake cable out of the support to clear the gear case.

15. When the gear case is free of the swingarm, remove the pivot bearing inner races from the gearcase. (before you drop them). Set aside IN ORDER.

16. Find a place to gently park the gear case.

17. Breathe. Mourn for what you’ve begun.


1. Wipe the old grease off the driveshaft ujoint socket and from the inside of the swingarm housing. You should be able to do a great job of getting the old grease out of the splines with the old toothbrush. Use solvent if you want to be fastidious. But don’t get solvent in the u joint.

2. Clean the splined shaft inside the gear case. Be careful not to put grit or dirt into the pivot needle bearings.

3. With a lint-free cloth, wipe and inspect the bearing inner races. Look for a nice clean, shiny, happy bearing race.

** I found my outboard bearing to have shiny spots corresponding to
each roller.  These turned out to be mostly cosmetic. We used some
super-machinery here at work to check wear depth on the bearing
races and they were shiny only, no measurable wear.

Replacing the bearings requires a Kukko puller (I used the big one
at the BMW shop- it barely fit. The tools fiche calls for a small
one but I couldn’t get the expanding gripper to expand far enough
to get a bite on the bearing.  Requires serious heat gun to
heat gearcase to install new bearing.

4. The manuals say to clean the bearings with solvent and dry with compressed air. (I didn’t since this was done at 16,000 miles for spline lube. I wiped them some…..)

Note: “Cleaning” involves solvent and rags in close proximity to the inside of the rear drive housing. My suggestion would be that rather than cleaning the bearings in place and probably doing a lousy job, just replace them at 40,000 miles. Removal for cleaning should be avoided because removal can be assumed to cause damage. (see heat gun & puller required)

5. IMPORTANT: Use the wire bristled toothbrush to cleanup the inboard pivot threads in both the swingarm and the pivot pin. Get these  REAL clean. The swingarm is aluminum. Aluminum threads can be damaged very easily by leftover loctite binding in the threads.  For test, thread the pivot pin into the swingarm to test for cleanliness. Keep cleaning until it threads all the way in smoothly.

6. By whatever means you wish (I spread it with a clean finger) , apply a thick coating of Staburags (or the new lubricant) to-

– the driveshaft Ujoint socket splines
–  the splined shaft in the gear case


1. Apply a thin coating of Staburags to the needle bearings in the gear case. (This re-greases them after wiping and helps stick the races in place later.)

2. Apply a thin, neat coating of anti-seize (I said ANTI-SEIZE) to the pivot surfaces of the pivot pins.

Place the inboard bearing race onto the inboard pivot pin. Apply a neat, thin coat of Staburags to the outside of the bearing race.
Position the pivot pins ready to hand near the swingarm where you  will need them.

3. Figure out a way to fix the driveshaft u joint relatively rigidly inside the swingarm cavity. The manuals recommend a thin, long screwdriver thru the u joint from swingarm pivot hole all the way across. More than one tool may be required to keep the little bugger in place. The important point is to use something that won’t damage the u joint and can be withdrawn after the splines have mated and as the gear case is pushed into position.

(This step needs a better solution. )


1. Move the gearcase to position on the scissors jack. Thread the brake cable back into the housing. (The cable will be an annoyance from now on.)

2. Find a stable position in which to rest the gear case.

3. With clean hands, apply a thin coat of Staburags to the outboard race outer surfaces. Don’t slop it to the inside of the hole where the pivot pin goes.

Stick the race into the bearing on the outboard side. (The one on this side can’t be installed after the gearcase is inside the swingarm.)

4. Gently fiddle and fuss with the gearcase to get the driveshaft socket and the gearcase shaft to mate.

Considerable foreplay may be required.

5. Once the splines have gotten together, ease the gearcase on up into the swingarm. Raising the jack gently will help with your hold.

Remove whatever you used to fix the u joint in place. (ALL OF IT!)

6. Visually align the outboard bearing and the pivot pin hole. Thread in the outboard pivot pin about one third of the way.

7. Visually align the inboard bearing with the pivot pin hole. Insert the inboard pivot pin WITH RACE into the bearing and thread the pivot pin all the way on by hand. Wiggle the gear case while inserting the pivots to help seat the bearings and races.

8. Reinstall the torque arm (hand tight) bolt to the gear case.

9. Reinstall the shock (hand tight)

10. Reinstall all the brake cable parts. Don’t tighten up much.

11. Now that you have something to wrench against, Thread the inboard pivot pin all the way in.

Unthread it about 2 turns and dab 1 or 2 (your risk for next time!) small drops of Loctite 273 onto the pivot threads and then torque to spec (75 ft-lb)

12. Hand tighten the outboard pivot pin “firmly” to pre-load the bearing.
Unthread a little then torque to spec (5 ft-lb ??).
Use a big box or adjustable wrench to seat the outboard locknut while  holding the pivot pin steady. Then, torque the locknut with the 27 mm socket to 75 ft-lb.

13. Remove the shock again.
Move the gear case up and down feeling for binding or play as best you can to confirm good bearing seating.


1. Reinstall shock.

2. Put the rear wheel on properly but leave the shock and torque arm fasteners hand tight.

3. Take the bike off the stand and bounce it on its wheels a few times.

4. Now torque all fasteners to spec. Double and triple-check all fastener torque settings and the brake adjustment.

5. Refill the gear case if you drained it.

6. Put everthing back where it went (tools, seat, etc)

7. Pickup your tools and put them away. Wash your hands and face. (don’t forget behind your ears)  Have some milk and cookies.

8. Carefully pre-flight the bike.


10. For the next few weeks, your preflight should pay special attention to the areas you messed with. Shock bolts, swingarm play, etc.

Disclaimer: Hey! I told you to sell the bike!

Ron Miller
DoD # 0693

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