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tranny input shaft

According to some extensive reading I did just now, 5 speed transmission have complete engagement through the clutch hub. They also have different spline profile and count (need confirmation)

EDIT:
This should be the list of 6 speed transmission bikes


R1200C (and all variation of cruisers, chromeheads i guess,) 1996-
R1100S 1998-
All 1150

Correction: Chromeheads have hydraulically activated clutch but 5 speed transmission. I am still trying to figure out different combinations of engines and transmissions.
 
PGlaves said:
If "this issue" means the less than fully engaged spline length, no. If "this issue" means stripped splines then yes. The possibility of a bent flywheel, misaligned shafts, rust, and the lack of lubrication affect 1100s as much as they affect 1150s I think. Of course, classic K bikes and Airheads also suffer from dry, rusty, worn splines too.
Click to expand...

I have not had mine apart yet but from what I have seen and read so far the 1100 splines do not fully engage either. Chris Harris's take on the problem. Warning: Expletives and some cursing ensues! :blah

http://www.youtube.com/watch?v=Jx3e0gqzylY
 
I did see the video but some other trustworthy posters have said that 5 speed transmissions have full engagement.
here is a list that i am using to piece the specs

http://www.bmbikes.co.uk/bmwmodels.htm
and in the video after he says "all of them" there is a pause and a cut,like he got ahead of himself
 
PGlaves said:
If "this issue" means the less than fully engaged spline length, no. If "this issue" means stripped splines then yes. The possibility of a bent flywheel, misaligned shafts, rust, and the lack of lubrication affect 1100s as much as they affect 1150s I think. Of course, classic K bikes and Airheads also suffer from dry, rusty, worn splines too.
Click to expand...

How come the K bike posts don't mention this? I have two, K75S and K1100RS and I am wondering if I have to worry about them like my R1100RT.
 
It is the 6 speed transmission that does not have 100% Spline engagement.
It mates to clutch plate 21 21 7 670 454

which is used in
R1100S
R1150GS
R1150GS ADV
R1150RT
R850RT '00 and on
R1150RS
R1150R
R850R '00 and on
R1200C 5 speed
 
Thank you. I am sure you go through this exercise probably more than you want, so I really appreciate you still have patience to share your knowledge on this subject.
 
roger 04 rt said:
The shape of the wear pattern and the color you mention seem somewhat diagnostic. What thoughts are there on when the material there is being heated more than the surrounding metal?
RB
Click to expand...

cele0001 said:
I am thinking that before the actual failure start there is weakening of the material due to heating.
My other random thoughts.

Clutch splines and hub connection has to be kept somewhat "lose" to allow sliding of clutch plate unlike a fixed spline hub connection where you are dealing with almost interference fit.

The shape of the wear pattern suggests that the clutch hub is slowly tilting on each impact,(because it must be slightly lose), more and more as the time goes. It is flexible enough to allow this movement and return to normal position when the things settle.Now, if there was full engagement this tilt would be met on the opposite side by clutch hub meeting the spline, (on the engine side) but since this second point of contact is missing things get out of control. Once the initial play is created it is only a matter of time.
I will try to get some pictures but I hope I am making sense. Sometimes the more you think about lines and angles the less sense everything makes.
Click to expand...

The explanation makes sense although I can only imagine a couple things which might cause the tilt: an out-of-flat flywheel or a misalignment come quickly to mind but don't easily explain the depth of the wear on the tooth.

Transmitted horsepower through the hub/spline during local and highway riding runs between 3 HP and 15, not very high. Only a tiny fraction of that can be lost in the joint and cause heating/wear. Wide Open acceleration at higher RPMs can result in 20-30 times as much transmitted power running through the connection. I wonder if the angles between hub and spline get increased as wear progresses and if there is any deforming of the connection under hard acceleration, leading to the heated areas you're seeing.

Going with this thought process for a moment, a longer spline/hub connection would better resist any twisting forces. It would also put the "sharp" end of the clutch hub over the relieved-groove at the inboard-end of the splines. I wonder if that is the reason for the grooves?
 
Without some serious testing everything is a speculation, but the most failures happen on the bikes with incomplete engagement,(maybe another speculation) so there are two possibilities:

1. Quality control on parts for these bikes is crap comparing to all others , despite the fact that supplier has no idea where the parts go, or care most of the time.
2. Failure happens largely due to the fact that there is incomplete engagement.

My joke is that the main reason Germans lost the war is that they were so busy measuring tolerances, while Russians were building tanks.
 
cele0001 said:
Without some serious testing everything is a speculation, but the most failures happen on the bikes with incomplete engagement,(maybe another speculation) so there are two possibilities:

1. Quality control on parts for these bikes is crap comparing to all others , despite the fact that supplier has no idea where the parts go, or care most of the time.
2. Failure happens largely due to the fact that there is incomplete engagement.

My joke is that the main reason Germans lost the war is that they were so busy measuring tolerances, while Russians were building tanks.
Click to expand...

Since we all have our own personal speculation as to causes, my candidate is improper lubrication: wrong stuff, put on poorly. Kinda like running your engine out of oil and asking if the rings might be in crooked!
 
OK, to clarify, I have an R1100RSL that was manufactured in June of 1993. Does this bike have full engagement of the trans input shaft splines with the clutch splines which is NOT the case with my '04RT?
 
jammess said:
OK, to clarify, I have an R1100RSL that was manufactured in June of 1993. Does this bike have full engagement of the trans input shaft splines with the clutch splines which is NOT the case with my '04RT?
Click to expand...

It appears that one is a 5 speed M97 and would have full engagement.
The 04 RT does not.
 
jammess said:
OK, to clarify, I have an R1100RSL that was manufactured in June of 1993. Does this bike have full engagement of the trans input shaft splines with the clutch splines which is NOT the case with my '04RT?
Click to expand...

It is yes on both questions what he meant to say.
Yes, your R1100RSL has full engagement, and yes, that is not the case with your 04 RT.
 
jammess said:
Do you know when BMW switched from the M94 trans to the M97?
Click to expand...

Got the answer to my own question. BMW used the M93 trans on the R1100RS until 09/93 when they went to the M94 so my 1100 has the M93. Apparently a change was made to the input shaft with the M97. Not sure what the change was. Seems I read somewhere that spline failures began showing up with the M97.
 
Transmission R&R

Took the transmission out today to inspect the modified hub. All OK. Took some pictures, hope to upload in the next couple of days. Total mileage 512 miles. I removed bolts that held the hub and installed rivets. I used 3/16 X 5/8 rivets. The holes on the hub are 5.2mm so I am at the limit as far as suggested rivet hole goes. I guess they were originally metric rivets. If anybody has a source for flathead solid steel rivets M5 X 14 (preferably) or M5 x 16 let me know. Everything that I found is "imperial. Next size is 7/32 and that is too big.
Also found out that clutch alignment tool is not needed at all. Socket over push rod is all you need. Slid right in. Comparing to automotive transmissions this job is a joke. Removal took less than an hour. Install about 2 easy pace. The fact that there is no airbox helps a lot. I have to source replacement bolts for the torx's bolts that are on the bike. There is no reason to have different fastener types.
Enough with brain dump. Off to watch some TV.

EDIT: I have a Rockster which is basically naked bike, I am sure RT is a different story, but shouldn't be that bad either.
 
cele0001 said:
Took the transmission out today to inspect the modified hub. All OK. Took some pictures, hope to upload in the next couple of days. Total mileage 512 miles. I removed bolts that held the hub and installed rivets. I used 3/16 X 5/8 rivets. The holes on the hub are 5.2mm so I am at the limit as far as suggested rivet hole goes. I guess they were originally metric rivets. If anybody has a source for flathead solid steel rivets M5 X 14 (preferably) or M5 x 16 let me know. Everything that I found is "imperial. Next size is 7/32 and that is too big.
Also found out that clutch alignment tool is not needed at all. Socket over push rod is all you need. Slid right in. Comparing to automotive transmissions this job is a joke. Removal took less than an hour. Install about 2 easy pace. The fact that there is no airbox helps a lot. I have to source replacement bolts for the torx's bolts that are on the bike. There is no reason to have different fastener types.
Enough with brain dump. Off to watch some TV.

EDIT: I have a Rockster which is basically naked bike, I am sure RT is a different story, but shouldn't be that bad either.
Click to expand...

Why not bore the holes out to 7/32? It's only .022" larger
 
I would have to drill not only the hub and the spacer but also clutch plate and the backing plate. I dont want to go there if I dont have to
 
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