Airhead Tech Pages
R Bike Spline Procedure
by Paul Kalichman
As requested, I have documented the procedure I followed for lubing the clutch
splines on my 1984 R80RT. It will apply for all 81-84 R80/R100's (dual sided
swingarm) I do not profess this to be the best method, after all I fix computers
not bikes! My now defunct dealer charged 1 hour for this service. I took 4
hours, including shopping time for supplies and tools, tool modification, and
lunch! Unfortunately I did not record the actual work time. The steps do not
have to followed in any particular order, I just numbered them for convenience.
The swingarm and battery tray could be done first.
- BMW supplied toolkit.
- Torque wrench.
- Crescent wrench for control valve, as correct size is not in BMW kit. (This
nut holds the valve that is connected to the pollution line running to the
exhaust manifold. It can be sized and seen above the line outside the airbox.)
- 27mm or 1.1/16 inch socket. (Ensure the socket and allen key fit before
starting. Grind/cut allen key,socket to fit, or find one's that do. I couldn't
- the short end of the key is too long, and the socket outside diameter
- Flashlight or trouble lamp.
- Remove gas tank
- disconnect speedometer cable, and battery ground for the cautious
- disconnect brake rod at rear wheel
- remove air filter
- disconnect pollution control lines at airbox
- loosen carbs at manifold
- remove plastic carb air supply tubes from airbox
- remove 1 pollution control valve (inside air box, right side) (for access
to mounting nut)
- remove 1 rubber air supply connector (inside airbox, left side) (for access
to LH mounting bolt)
- disconnect 2 vacumn hoses that will be in front of bolts
- remove swingarm locknuts
- remove swingarm pivot pins
- remove 4 10mm nuts securing battery tray
- loosen LH tranny bolts (upper in airbox, lower in front of shifter)
- remove RH tranny bolts (upper in airbox, lower in front of brake lever)
CAUTION: DO NOT remove LH bolts completely to insure tranny can not
somehow fall completely off engine.
- pull in clutch lever to separate tranny from engine
- pull battery holder up and out of mounts and towards rear. (this is for
This should give about 3/4 inch gap between tranmission and engine. Inspect
splines and clean if possible. If you do not see splines, re-assemble, and
go have a drink, you're too late! Re-apply a small amount of your favorite
high tempurature grease with a tooth brush or screw driver. If you see grease,
be happy you just wasted your time. If you see splines but no grease, be happy
you didn't waste your time, but wonder if you're in time!
- Operate clutch a couple of times to re-align tranny before completely tightening
- Swingarm must be centered between frame.
- Pivot pin torque is 8 inch/lbs. (this is the bearing preload) (see procedure
- Carbs will need to be leveled and adjusted. (you do have carb stix right!)