BMW Oilhead PDF Maintenance Manual

Cold Engine and Drivetrain Procedures
Note: In most cases the alternator belt does not need to be checked any more. Early models should have the pulley and belt upgrade that came out a few years ago. Current recommendations are that the belt is installed and adjusted, then not disturbed until 36K when replacement is specified.
1. Remove the four bolts holding the black plastic alternator belt cover at the front of the engine, 4mm T-handle hex.
2. Remove the cover by sliding it straight down.
3. Check the belt for cracks or shredding.
4. Check the belt tension, quite tight, ~1/4” deflection when you press on the center.
Note: Paul Glaves suggests that proper belt tension is when you can twist the belt ~90 degrees, midway between the pulleys. If you can twist it more than 90 degrees, it is too loose. If you cannot twist it 90 degrees, then it is too tight.
5. Leave the cover off for the valve adjustment procedure on the next page.

Change Alternator Belt
1. Remove the four bolts holding the black plastic alternator belt cover at the frontof the engine, 4mm T-handle hex.
2. Remove the cover by sliding it straight down.
3. Loosen the 2 nuts and 1 bolt, 13mm, that hold the alternator – one is on top and one is on each side, thus allowing the alternator to pivot down.
4. Remove the old belt. (Some bikes have a pipe that traps the belt – loosen it enough to get the old belt out and the new belt in)
5. Install the new belt being sure it is properly seated.
6. BMW calls for a tensioning torque of 5.9 ft.lb. (8 Nm) on the adjuster bolt on the left side of the bike. You have to get at this bolt from the alternator side and you may have to lift the tank. Alternatively, you can pry the alternator up with a large screwdriver to tension the belt.
7. Once the belt is under proper tension, tighten the 2 nuts and 1 bolt, 13mm, to 15 ft.lb. (20 Nm).
8. Check the belt for proper tension (see above) and proper seating alignment.

Valve Adjustment
1. Remember – engine cold!
2. Bike on centerstand.
3. Transmission in neutral.
4. Remove the black plastic valve cover protectors, if installed, using a 5mm T-handle hex wrench.
5. Remove the black valve cover strip by pulling outward on the end where the plug wire goes under it.
6. Pull the plug wire cap off the sparkplug using the special black plastic tool in your BMW tool kit.
7. Before removing the sparkplug, blow compressed air around the plug well – there is often dirt here that can fall into the cylinder when you remove the spark plug!!!
Note: If you do not have an air compressor, you can get a compressed air tank at any Xmart automotive department, or you can get a small can of compressed air at any photo or computer supply store.
8. Repeat again after turning the spark plugs a couple of turns.
9. Remove the spark plugs using the tool kit spark plug socket or 5/8 in. deep well very thin wall socket.
Warning!: It is very easy to get a spark plug socket stuck in the plug well. If your socket does not slide onto the spark plug easily, do not use it!!! Use the spark plug socket in the BMW tool kit instead. I welded a nut onto the end of my BMW socket so I could use a torque wrench on it when installing the spark plugs.
10. Place an oil drain pan under the valve cover.
11. Remove both valve covers using a 6mm hex socket and ratchet.
Note: Loosen the valve cover bolts until you can pull them part way out. They stay in the valve cover – do not try to pull them all the way out.

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