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Camshafts, broken cam tips, cam sprockets,
lifters (followers), alternator & cam seals,
crank nose bearing, etc.
Sports-cams installations.
Assembly lubricants.

© copyright, 2008, 2010, 2017, R. Fleischer

Article 60, sub-section 7, at:  
http://bmwmotorcycletech.info/cams.htm

This article is meant to be used with the following articles:

http://bmwmotorcycletech.info/timingchain.htm  comprehensive on the crank, timing chest sea ls, oil pump, etc.

http://bmwmotorcycletech.info/flywheelremovalwarning.htm

Preface. The importance of proper engine oil:
Most any engine oil will work reasonably well for most of the engine, but there are specific areas of the engine that will be damaged, and perhaps expensively, if the oil is not of proper quality and that means proper additives that are blended by the oil makers. The author's website, http://bmwmotorcycletech.info, contains several long articles on how oil really works, what oil should be used, etc.

Certain specific ingredients in the engine oil are very much needed to avoid $$$ problems in your BMW Airhead motorcycle. THREE are critical. One of them is ZDDP (or ZDP).  In the vast bulk of commonly available oils at any autoparts store, the amounts have been DEcreased over time in accordance with API, SAE, and oil and auto manufacturer's changes. Your Airhead motorcycle requires this additive, in a proper formulation, in a minimum (and maximum) amount, to avoid $$ spalling and other deterioration of the camshaft and cam follower surfaces. Another ingredient is needed to be sure that under storage conditions, the cam and followers (and other items in the engine) do not have the oil dripping off and leaving the metal unprotected at engine startup. The final ingredient of major importance is that the amount of detergents (Increasingly higher in modern car oils) should not be excessive, as that defeats both long term storage metal protection and defeats the protection of ZDDP.

Here's a few photos of cam and follower damage:

cam damage  cam follower damage

 

Broken tip on pre-1979 Airhead camshaft:

This relatively serious problem is seen now & then. The cause is typically from over-torquing the nut holding the automatic advance unit to the camshaft tip. It could have been abused long before you got the bike, weakened, then it was YOUR unlucky day to snap off the tip ....even using proper torque. Officially the nut torque, at least in one BMW manual, is .6-.7 Mkp. 0.7 Mkp is 6.86 Nm or 5.1 ftlbs. I would not go that high. 4 footpounds is, I think, more than plenty high enough. MOST torque wrenches that read, perhaps, to a maximum of 75 foot-pounds are not accurate at low settings of 4 or 5, even if they can be set that low at all. If you must use a torque wrench, use an INCH-pound wrench at maximum 48...or some other lower torque type of wrench (inch-ounces??), with appropriate conversion of values ...there is plenty of information on torque, torque values, etc., using the torque wrench, conversions, etc., on the author's website, see articles 71A, 71B, 71C.

I personally tighten these nuts by feel, and I use the original type of washer or a waverly locking washer. I do not use a split-type of washer. Nuts need not be overly snug, but must be snug enough so the nut does not back off! I never over-tighten these nuts! Do not use Loctite on these nuts.

What to do if the tip does snap off:

A Boyer ignition will likely fit, but you can likely fix the tip, if you do the following very carefully:  

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© copyright, 2008, 2010, 2017, R. Fleischer