Riding Style & Tranny Bearing Life

[Oaktown]

I took my '07 R12R with 65K miles into the SF dealer for what I knew would be an expensive service: new ABM rotors, EBC HH pads, brake flush, Ohlin steering damper, new rubber boots @ both ends of final drive ($150 parts!), change all fluids, adjust valves & balance throttle bodies and perform fuel pump campaign. This was going to approach $2K with parts and labor, but it was time to do it all, especially since I have a ride to Utah scheduled for next week, I wanted to be confident crossing Hwy 50 in Nevada. I think the service manager is calling yesterday to tell me the bike is ready, when the news is about the transmission: "The tech is hearing some tranny sounds that are indicative of a serious problem." After I approve six labor hours to diagnose the exact problem, it turns out that two bearings are toast, one not good and three are OK. It only seems reasonable to replace all six since the tranny is apart in their hands and much of the cost is access and reassembly, so another $1,163.00 was approved. At first I was very disappointed in what I consider far too few miles ridden to require this expensive repair. After all, the CHP has some R12's on the road with over 150K miles and those guys ride them just as hard as you'd imagine, so WTF happened to my tranny? Then I got to thinking: I am a near-constant short-shifter, rarely exceeding 5,000 RPM before shifting up. I weigh 240 lbs. and usually have the side cases on with stuff adding another 50 lbs. or so. The question I have is: Have I been putting stress on the tranny and decreasing its life with my riding style? Time to wind it up higher before shifting? Thoughts appreciated in advance.

John

[Bob Ain't Stoppin']

John, I would think that the bearing life in the tranny is more a function of the oil you use and the change interval. Riding style would more likely affect the shifting parts. Oddly enough I recently changed the trans oil, using the same Castrol stuff as always, and quickly found that the shifting was not as smooth as before. Haven't figured out why yet.

I just rode 50 in Nevada. This is the "loneliest road in America", but I found it very interesting. Mountains (admittedly small ones) all around for most of the way. I'm thinking that I'll be a multi millionaire if I can find a profitable use for sage brush. Getting into Utah on 50 quickly changes the landscape into barren and 'lonely' desert.

[tinytrains]

There really should not be anything you could have done to damage the bearings. My guess is one just had bad metallurgy and started to fail. that produced debris which ate the other two. In which case changing them all is a very good idea. Transmissions on these bikes are not normally a problem.

Good luck.

[Steve H.]

+1 Tynitrains!
On the other hand rpms shifting at-high or low-will not affect bearing life.If you are a"calm"driver or let to say a touring style driver,everithing mechanical from the engine to the FD would last longer.In you case one faulty bearing messed up everything I assume.Once the tranny is out and in parts,best is to change everything worn and suspicious.I wold do the same.

Steve H.

[Oaktown]

Thanks guys. The tranny work has been done and it no longer makes a "whirring" sound when running in neutral and the clutch out.

[MTBeemer]

On behalf of mother BMW, and despite what others have said; it was your fault, all your fault and certainly not BMW's fault.

[P_Jensen]

Makes one wonder if the factory lubrication schedule and recommendations are enough? I have wondered about that with a cat just below the trans shedding heat how it would affect the life of the trans oil and the trans. I did notice eariler this year at the dealers that the weight of the factory gearbox/final drive oil was now a 90-140W vs the previous 90W.

[Steve H.]

I use in trany 75w140,in differential 75w90 both synthetic oils 75w140 considering the heat from the engine+cat. The differential is away from engine and cat.

[deilenberger]

I use in trany 75w140,in differential 75w90 both synthetic oils 75w140 considering the heat from the engine+cat. The differential is away from engine and cat.

I do also - but a consideration - if the bearings used are like the ones used on earlier BMW transmissions - most of them are a sealed/greased bearing. The oil doesn't lubricate them. One clue to a bearing failing on earlier transmissions was the oil turning dark from the grease escaping from the bad bearing. Wonder if that's what inspired the service department to explore this transmission.. if so kudos to the mechanic who spotted it and knew what it meant.

[ammolab]

The Bearings on the output shaft of my R50/5 failed twice. Second repair found that the shaft was not properly shimmed to eliminate side load on bearings when the case was bolted together. After that second repair I had no further transmission problems.

[Steve H.]

Yes,Ammolab I have had bearing problem on freightliner fld.It happened twice.The mechanic didn't know why it happening.That was driveshaft input into transmission. Shortened the shaft by 1/4" and never had that problem again.I never had a chance to see BMW trany taken a part,so I don't know is there a seald or non seald bearing.The final or output bearing should be so called "one side seald"bearing-logikly-alloving gear oil to lube the bearing still preventing oil to eskape from transmission.Both side seald bearings-in this case-doesn't have to much sence.