BMW K75 K100 Final Drive Driveshaft Spline Failure Causes

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1. New driveshaft is worth the money, while available.  No grease fittings.. dumb.
   Paralever ( on K-100)  isn't going to fly without the rear spline being outside the bevel gear assy.  Is paralever worth the trouble ?  Nope.
2. The rubber shock coupling in the middle of my K-100RS( 4 valve)  failed before 10K miles... this is simply a shoddy part.. and not maintenance related ( although the 2 young guys before me might easily have been stupid ! )  So on this I will agree.. crummy part.   Worse, the dealer was so lame they couldn't do a proper compression test... and told the P.O. that bike needed a valve job.  I bought it because it ran like a watch, and clearly did NOT have any compression/engine problems !  In went the new drive shaft, and I drove away happy.  Vroom Vroom.
3. Paul,  Your K-75 and Mine are at least 19 and perhaps as much as 26 years old. The lubrication interval needs to be observed.  Your bike might only have 35K miles.. but it is long long overdue for spline lube.   The Honda Moly ( molybdenum)  spline lube product is so superior to the BMW label goop... that beemer dealers routinely use it !   The "bitch" isn't the dry clutch automotive type drive-line... but rather the crummy lube that was used during manufacture.. and perhaps subsequent maintenance.  You are clearly smart enough to have done your own clutch replacement. "Misalignment"  is pretty darn hard to achieve between the clutch and transmission.  Now, if you don't happen to like the dry clutch, separate transmission architecture.. why not buy a similar Honda or Kawasaki.?  The used  K-75 represents one of the finest used motorcycle values available.  They are capable of 300K mi endurance.  During the 50 years this is likely to happen.. stuff is going to fail strictly from age, and more from deferred maintence ( by previous owners).  Once sorted, these bikes repay you with economy, safety, and comfort.  The K-75 is reasonably sporty, and over the long haul reasonably comfortable.  All machines have their strong and their weak points, both in terms of failures, and repairability.  Relative simplicity, low parts count, and field serviceability with hand tools is the strong suit here.  too expensive new, but great bargains used... with the caveat that doing your own work is the key to making financial sense out of owning a BMW.  Post K-1100... I wouldn't touch one. too complex, too big, too prone to failure.  But your K-75.  One of the real successes of BMW after the R-75/80.
4. Any videos available for a K75S (engine) oil change (especially showing the 'belly-pan' removal) ?
   Thnx,
   Dan
5. wet clutch are crap they will burn much faster when mis threaded
6. no problems with japanese bikes is bullshit, most bmw are old too.....
7. I like your method of recording the date,mileage,& Moly 60, on the transmission case! Slick.
8. The Softails had belts manufactured by Gates. They are IMO the best system for,cost,maintenance,& fuel efficiancy.
9. Good essay. The Yamaha XS750 had its drive line system designed by Getrag AG. In Germany. I owned Harley Softails and they were easy to adjust & maintain.
10. The pinion splines of the bevel drive / driveshaft rear tube portion are to be CLEANED and lubricated with either a moly-based grease or the proper Staburags NBU30PTM every time the rear tire is replaced (8,000 miles). Failure to do so will result in spline failure at the back usually around 40,000 - 50,000 miles. Proper repair performed by Bruno’s Machine & Repair consists of the driveshaft tube being resplined and plugged to retain grease and the pinion splines rebuilt and made 13 mm longer. 
11. The transmissions input shaft splines / clutch friction disc splines are to be cleaned and lubricated every 20,000 miles on Airhead and 2 valve K's. All Paralever models including Oilheads are to have this done every 40,000 miles. This requires removing the transmission. BMW stopped listing spline lubes in the 1990's likely due to the ridicule they received by the motorcycle press regarding these outrageous service intervals. Any experienced BMW tech should know this and now you do as well :) 
12. My dealer stated that BMW does not offer an interval for greasing the splines. My owners manual does not list this either. Can you provide picture of any documentation from BMW that states the interval for this procedure?
13. You are welcome.
14. My dealer stated that BMW does not offer an interval for greasing the splines. Can you provide picture of any documentation from BMW that states the interval for this procedure?
15. Correct, the design requires lubrication - however, BMW did not include this procedure in the maintenance schedule. It can happen at low miles as the bike ages and the grease dries up. Many owners learn after a costly drive failures that an informal "schedule" was developed. Shafts in all other bikes are tried and true technology that offer almost no maintenance. I have yet to see an explanation for the benefit of the BMW dry design? Even BMW has abandoned this design.
16. Ouch, did you replace it? If so pleas post updates. Thanks.
17. lol! Thanks for the humor!!!!!!! I loved it!!!!
18. Good, I loved my bike too. Remember, this is not an attack on the brand. New models are being changed and improved but owners of the k75 need to know three things about the k75s drive system: 1. it is very strong (it is the same shaft used on powerful k1100) 2. it needs good quality grease to keep it in good working order 3. If it is taken care of it will probably last 150K miles or more. Follow this program and it will not fail. If you shaft is worn this video shows you how to fix it.
19. I don't know about this model so I can really speak to that problem. It does not sound like a design flaw to me. Remember, if a seal is not put in correctly at the factory or is compromised during wheel removal for tire changes (I don't know if that is possible for your bike) then a leak can develop which is not the seals fault. You would need to gather information on how often this happens and at what mileage and other info like how hard the bike is ridden, hot / cold climate etc. Good luck
20. I LOVE never seize (a mix of graphite powder and oil). My answere is no. Never seize / Anti-Seize works best on parts that don't or rarely move like bolt threads and lug nuts on a car. Or the spline on the bmw k75 rear wheel - not the drive shaft but the spline that the rear wheel slides on to. I have found in wheel bearings or other parts that move a lot and fast it does not provide good lubrication the way engine oil, gear oil or grease does.