Down shifting!

Recently I noticed a little trouble downshifting on my RT. When downshifting, the pedal seems to be stuck but adding a little more pressure or force it will go down. A minor inconvenience right now but is this a harbinger of something worse to come??
Now the last ride I took it was freezing and I still have 80/120 transmission oil in it.
It still should warm up after 10-15 miles shouldn't it?
Thanks in advance.

Time for a tranny input spline lube?

DarrylRi said:

Time for a tranny input spline lube?

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yup. i had about 3-4,000 miles from the time my R11S started doing that to the time the input shaft grenaded. It was mostly 4 to 3 shifts, but eventually some 3 to 2s as well. not even every ride, & not nearly every shift- maybe just once a ride at most, and the rest of the time it was like buttah (well, German buttah. never has felt like Italian buttah). then....kablooey! no go nowhere.
if that's what it is, a lube may save the shaft replacement, maybe not. not lubing will guarantee a larger (read: more $) job.

prventative maintence

Every other riding season I lube the splines. And yes at the end of the second season downshifting to second gear becomes diffucult. I now have 60,000 miles and my mechanic just completed this service. He reports the splines show minimal wear at this time.

I use 90W GL-5 in my '95 1100 per manual , 120 sure seems heavy ,especially in cooler climes. Also just spline lubed Helen's 1150 doing a hard into neutral condition with expected payoff

DarrylRi said:

Time for a tranny input spline lube?

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+1! I did a spline lube a year ago. Splines were dry, but the damage looked minimal (as far as I could tell).

Another often overlooked maintenance issue is the shifter linkage and the pivot for the lever. When my R1100RS gets a bit harder to shift, a good clean up and re-lubrication of the lever returns it to a more effortless action.

Spline lubes should not be overlooked either.

I cannot see what trans input shaft lube has to do with shifting gears in the transmission. If the clutch is disengaging the engine from the trans which it will do input shaft lubricated or not then anything other than a smooth shift points to the transmission itself nothing more. I notice a tendency for the trans to become noisier when hot and slowing down in the lower gears. Shifting also seems a bit harder when hot. I tried a multi viscosity synthetic gear lube in the trans and shifting did seem smoother with less trans whine in lower gears. Again, I can't see how input shaft lubrication could have anything to do with gear changing if the clutch is doing its job and properly disconnecting engine output from trans input. Input shaft spline wear might be caused by mis-alignment between engine and trans or too soft metal used to construct the trans input shaft or maybe insufficient spline surface area in contact with the clutch splines. Lubrication of input shaft will simply not correct any of these conditions. Remove the starter motor and while operating the clutch lever observe for yourself how small is the amount of travel of the cluch plate in relation to the trans input shaft. Forever lubricating these splines might make one feel good but not much more. If my input shaft ever fails on my '04RT I plan to replace it with the Canadian built input shaft which is made of harder material and has greater contact area. I might even lubriate it as well.

Red100RT said:

I cannot see what trans input shaft lube has to do with shifting gears in the transmission. If the clutch is disengaging the engine from the trans which it will do input shaft lubricated or not then anything other than a smooth shift points to the transmission itself nothing more. I notice a tendency for the trans to become noisier when hot and slowing down in the lower gears. Shifting also seems a bit harder when hot. I tried a multi viscosity synthetic gear lube in the trans and shifting did seem smoother with less trans whine in lower gears. Again, I can't see how input shaft lubrication could have anything to do with gear changing if the clutch is doing its job and properly disconnecting engine output from trans input. Input shaft spline wear might be caused by mis-alignment between engine and trans or too soft metal used to construct the trans input shaft or maybe insufficient spline surface area in contact with the clutch splines. Lubrication of input shaft will simply not correct any of these conditions. Remove the starter motor and while operating the clutch lever observe for yourself how small is the amount of travel of the cluch plate in relation to the trans input shaft. Forever lubricating these splines might make one feel good but not much more. If my input shaft ever fails on my '04RT I plan to replace it with the Canadian built input shaft which is made of harder material and has greater contact area. I might even lubriate it as well.

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The clutch disk has to shift axially slightly to fully release from the flywheel. If the spline is nearly shot and there is a ridge on one of the spline surfaces, the disk can't shift axially and will continue to drag on the flywheel, making shifting hard.

A harder shaft might help, but the BMW shaft is already quite hard, and the clutch ID seems to be the first element to go anyway in the pictures I've seen. A longer spline would also help but the potential improvement is so slight it isn't worthwhile

I agree, the problem is alignment. If the transmission is out of alignment with the flywheel rotation axis, the spline has to drag clutch disk around the face of the flywheel once per revolution, causing fretting corrosion in the spline. Once the alignment is fixed, the spline should last indefinitely.

Spline wear condition can be monitored by removing the starter and critically evaluating the buildup of wear debris in the clutch housing, and looking at the clutch disk-to-input shaft backlash.

Thanks

Thanks for the input. At least I can talk to my dealer with a little less embarrassment.

Post in Online Central

Time and time again we read about this problem from other riders. Ultimately, it ends up being a transmission rebuild $$$$
Have a look at the post in Online Central "2856" for what BMW-North America says is the culprit to our problems.

I agree that if binding happens when the clutch disk shifts along the spline axis then complete disengagement would produce hard shifting. Actual clutch movement is very slight as well. It is hard for me to see how these worn splines produce enough tendency to bind against the forces applied when the clutch lever is depressed causing desired disengagement. I mean this is an hydraulically operated clutch mechanism after all. I wonder if this drag could be observed or tested for after removal of the starter motor somehow?

$1000.00 round trip

My dealer said it costs $1000.00 dollars round trip (disassemble/reassemble) to inspect and lube the input shaft. That's a lot of cake to pay every other year! What am I missing here? Note: I'm not a "wrencher" - no tools , no time, no knowledge.

"What you didn't know" is that your dealer is typical "brand pricey". my "used-to-be-head-wrench-at-BMW-dealership (and one of only 2 or 3 BMW Master Techs in CO)-but-now-owns-his-own-shop" friend quoted my $600 lubing my R11S.
unfortunately, my occassional hard downshifts morphed themselves into a splinectomy, created entirely by the bike. Another local shop did a full repair of the input shaft and clutch (both were thoroughly creamed) for $1400.
moral of the story- you don't have to go to the dealership. This job is basic nuts & bolts, so even if you choose not to do it yourself, you can go to a trusted/knowledgeable wrench and come out for less $.

of course, you could come out to CO every other summer, have Steve http://www.beemersandmore.com/ do a lube on the splines, and then head on over to Paonia for TOR. Brilliant! And the $400 savings over what your dealer suggested would nearly pay for the vaca!! Double Brilliant!!

btw- general wisdom (translation: Paul Glaves) recommends lubing shaft splines every 40,000m. or so, with Honda Moly 60 paste (although he custom blends his Moly 60 with a molybdenum compound).

IMO, if the tranny is aligend, the splines will last forever, lube or no lube. If the tranny is misaligned, the splines are going to strip out every 30K miles. Lubing the splines may increase the mileage to 35K, but it is inevitable.

Hey OP, two things. First, hard downshifting, I'm sorry to say, is generally not a good sign. Second, you may be able to check the health of your splines by removing the starter, squeezing the clutch, and seeing how much radial play you have by reaching in with a thin screwdriver and moving the clutch plates. No movement is good. A slight movement is OK. significant (1/4 inch or more) movement is bad. Check it out and let us know.

JimMoore said:

IMO, if the tranny is aligend, the splines will last forever, lube or no lube. If the tranny is misaligned, the splines are going to strip out every 30K miles. Lubing the splines may increase the mileage to 35K, but it is inevitable.

Hey OP, two things. First, hard downshifting, I'm sorry to say, is generally not a good sign. Second, you may be able to check the health of your splines by removing the starter, squeezing the clutch, and seeing how much radial play you have by reaching in with a thin screwdriver and moving the clutch plates. No movement is good. A slight movement is OK. significant (1/4 inch or more) movement is bad. Check it out and let us know.

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Agreed Jim, lubricating splines isn't going to solve anything if trans is mis-aligned. I think pulling started motor and inspecting for metal filings and radial play is about all the preventive maintenance you need. I still have a hard time believing that lubricating dry spines that are otherwise in good shape can improve or make for smoother shifts. I mean when that clutch lever is pulled in that clutch will disengage lubricated splines or not.

Red100RT said:

Agreed Jim, lubricating splines isn't going to solve anything if trans is mis-aligned. I think pulling started motor and inspecting for metal filings and radial play is about all the preventive maintenance you need. I still have a hard time believing that lubricating dry spines that are otherwise in good shape can improve or make for smoother shifts. I mean when that clutch lever is pulled in that clutch will disengage lubricated splines or not.

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Do spend the time to read up on this issue...hard downshifting is the warning bell for worn splines. The splines on the 6 speed do not project all the way thru the hub. They are short by a full 6mm. The ridge that develops on the splines (stock shaft) does not let the clutch plate slide freely on the splines, thus affecting downshifting
You can start reading here.... I ended up having a longer input shaft made having go thru this twice http://www.advrider.com/forums/showthread.php?t=207014&page=10 see posts 98, 128, 140

It's a long read start to finish but a lot of info

Good idea

of course, you could come out to CO every other summer, have Steve http://www.beemersandmore.com/ do a lube on the splines, and then head on over to Paonia for TOR. Brilliant! And the $400 savings over what your dealer suggested would nearly pay for the vaca!! Double Brilliant!!

Good Idea Fish. I got a son that lives in Golden. I could go out there and pay him a visit while my bike's in the shop!

GSAddict said:

Do spend the time to read up on this issue...hard downshifting is the warning bell for worn splines. The splines on the 6 speed do not project all the way thru the hub. They are short by a full 6mm. The ridge that develops on the splines (stock shaft) does not let the clutch plate slide freely on the splines, thus affecting downshifting
You can start reading here.... I ended up having a longer input shaft made having go thru this twice http://www.advrider.com/forums/showthread.php?t=207014&page=10 see posts 98, 128, 140

It's a long read start to finish but a lot of info

Click to expand...

I read that piece already. If the spines are worn to where this ridge has developed to affect clutch radial movement then why bother lubricating a defective input shaft and then go to al the work involved to put the whole works back together again without replacement? I can see where this ridge can be an indicator of a damaged input shaft if clutch disengagement is affected. I cannot see how this condition is an indication that lubrication is required and I cannot see how regular routine lubrication can prevent this condition from developing. Also, if this ridge has developed lubricating and re-assembly could not possibly improve shifting for any length of time at all before the lubricant is simply scraped away so why bother? I think this is maybe why nowhere in my owners manual is spline lubrication listed as required maintenance. I agree the after market harder longer input shaft is a good idea but not sure how this will correct a trans engine alignment problem. Also hard to believe that BMW has not corrected this spline issue years ago going back to the days of the R100 at least. If my machine ever needs an input shaft replacement I will for sure go with the Canadian replacement shaft.

Oh, not to change the subject, but it does seem like BMW does spend time reinventing the wheel. An example is the final drive failures that seem to plague the oil/hex/k bikes as of late. Now BMW has been building reliable final drives for a lot more years than I am old and now, all of a sudden, they forgot how? Give me a break

I don't have to worry about input shafts or FDs anyway what with all this ice and snow as far as the eye can see.

Red100RT said:

If the spines are worn to where this ridge has developed to affect clutch radial movement then why bother lubricating a defective input shaft and then go to al the work involved to put the whole works back together again without replacement?

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Agreed, shaft must be replaced, lubrication is only a short term fix.