I took apart an M97 transmission '99 R1100GS

[mark883]

Originally Posted by Galen

Well done!
I wish you were my neighbor.
I have an M94 that skips in 5th gear (was rebuilt once for the 2nd gear skip) and I have a donor M97 (bad housing and maybe a sloppy input shaft)...
Maybe I'll venture into it this summer, bolstered with confidence after reading about and seeing what you've done.
Thanks for the writeup!

Sounds like you have real work there. There may be a totally different bearing on your M94 input shaft. There may well be some interchangability, but you best ask someone like Anton. Sounds like you will get into some shimming, if you start swapping shafts around.

If you can do the R&R of the trans., that can save you some serious coin right there, and make the professional rebuild of the trans a bit easier to absorb.

Hardest part really was the heating of the case halves to get the shafts in & out.

[mark883]

frack!





Luckily, I carry protection, so I figure, let's tear into it!



Carefully pry it out... multiple stick & prys for maximum effect.



Inspect the big bearing.......

All rivets in retainer ring are accounted for. Insert a couple wheel bolts, and spin... no chunks, grinding or hard turning. No wiggling when trying to jocky the bearing.

I also looked as close as I could at the outer and inner bearing race, and nothing appeared amiss. Checked again after rotating things around. Sorry, no good pics of this. The races are hard to see, but I do know what a grindy bearing feels like. This didn't.

Flushed things out with brake cleaner... old oil, clean out the breather, clean sealing surfaces.



GENTLY tap in a new seal, working around the surface in a circle. You can't get it in on one blow, or one lap around the seal. Take your time. Maybe I should have custom turned a seal driver, but I don't know how to use a metal lathe.

Fill with oil.... let sit overnight... hope it doesn't leak again.

The stool sample from it looked good, as best I can tell. No chucks. However, there may have been a small shiny flake. That has me a bit worried. I will need to watch and observe.

If it takes out this new seal, I know what the answer is. The removed seal was the original, best I could tell. 45k miles, 12 years, hopefully the seal was all that it was.

[mike54]

Those seals have been known to leak. I replaced mine at about 60,000 miles and no issues in the last 35,000 or so. Should be fine.

[YetiGS]

Ironically (or not) I got home tonight, went inside for a while and went out to the garage to get a beer. Found a wee puddle under the final drive. "Hmmmn, what's this? Oh fuck! "


Pulled the wheel and saw that it was definitely leaking past the seal. Removed the seal and saw the same thing you did. Happiness. No missing rivets, cages looked good and everything rotated smoothly!



The weird thing is, I went to look at an 1150 yesterday. Guess my 1100 wasn't pleased and wanted to let me know I better not think about cheating again!

[mark883]

Originally Posted by YetiGS

Ironically (or not) I got home tonight, went inside for a while and went out to the garage to get a beer. Found a wee puddle under the final drive. "Hmmmn, what's this? Oh fuck! "


Pulled the wheel and saw that it was definitely leaking past the seal. Removed the seal and saw the same thing you did. Happiness. No missing rivets, cages looked good and everything rotated smoothly!



The weird thing is, I went to look at an 1150 yesterday. Guess my 1100 wasn't pleased and wanted to let me know I better not think about cheating again!

$30 seal. Much cheaper. And, you know, the 1100s are bestest.

[YetiGS]

Originally Posted by mark883

$30 seal. Much cheaper. And, you know, the 1100s are bestest.

Yup. She just keeps kickin'

[mark883]

Well, I think I can put this one to rest.

After a 30 mile test run, and letting it sit overnight, it appears that the final drive seal sealed things up.

I would say the trans shifts better now. Not 10x better, just better than it did. Maybe some of that is cleaning up the semi-petrified clutch spline lube (very heavy grease- almost beyond grease, towards glue), and maybe some is having the input shaft back to 'normal'. The splines were nowhere near dry, nor rusty, and I've never done water crossings with the bike.

The 2-3 shift is still a bit crunchy, if not done totally correct, but I think that's a BMW oilhead thing. My guess is, ( I could be wrong) there's a lot moving for the 2-3 shift inside the trans- some gears are a simpler throw inside than others- mainly just moving one gear. So, I think, with 2-3 there's more time between gears to mismatch the revs, hence the slight 'chunk' in the shift. But looking at my gears & dogs, I didn't see that it has hurt anything yet.

Hopefully everything holds up, and I'm good for a bunch more miles. At 45k miles, my GS engine is just getting broke in.

[YetiGS]

Originally Posted by mark883

Well, I think I can put this one to rest.

After a 30 mile test run, and letting it sit overnight, it appears that the final drive seal sealed things up.

I would say the trans shifts better now. Not 10x better, just better than it did. Maybe some of that is cleaning up the semi-petrified clutch spline lube (very heavy grease- almost beyond grease, towards glue), and maybe some is having the input shaft back to 'normal'. The splines were nowhere near dry, nor rusty, and I've never done water crossings with the bike.

The 2-3 shift is still a bit crunchy, if not done totally correct, but I think that's a BMW oilhead thing. My guess is, ( I could be wrong) there's a lot moving for the 2-3 shift inside the trans- some gears are a simpler throw inside than others- mainly just moving one gear. So, I think, with 2-3 there's more time between gears to mismatch the revs, hence the slight 'chunk' in the shift. But looking at my gears & dogs, I didn't see that it has hurt anything yet.

Hopefully everything holds up, and I'm good for a bunch more miles. At 45k miles, my GS engine is just getting broke in.

Glad to hear that both of your problems are solved. My FD seal replacement did the trick too! Glad to know that mine isn't the only GS with the slightly, notchy 2 to 3 shift.

[Transrider5587]

Just food for thought...Most peple are over critical of their own work. I replaced 3rd and 5th gear in a little Yamaha 225 I still have....I know it was half the job of a GS transmission, but still transmission work. When I drive the bike I still feel a long hard shift into 5th. Why do I feel it because I should have replced one more shift fork but went cheap. The bike is kind of a pass around now. One that every one ends up riding. When other people ride the bike they are shocked at how nice it shifts and runs. When I ride it, all I feel is LONG shift into 5th. The feel of the shift into 3rd with your bike might just between your ears. From the post you did outstanding work, and sure didn't miss anything. Congraulate yourself and go ride that bitch hard!!!

One last thing great post!

[reyb]

Great thread Mark883. I've been googling recently regarding my 2000 R1100R tranny. Initially, I thought the noise I'm hearing was the throwout bearing but after all the articles I've read it seems that it's the tranny's input shaft. Some questions I have about your tranny rebuild are:

1. How did you heat up the bearings without melting the seal? I replaced my final drive bearings(big and tapered) and put them in the oven. However, they didn't have a seal, so I'm afraid that if I cook my bearings I'll melt the seal.
2. When I replaced my FD bearings, I used a bearing puller I got from Sears. Looking at the tranny input shaft, I'm thinking I would pull the bearings off by grabbing/pulling the gears which would pull the bearing off. Is this what you did?
3. Did you use a press to press on the new bearings? Which the large bearing on my FD, I used the old bearing to hit on(gently) to drive in the new bearing which worked fine.
4. Any chance your friend's son would "rebuild"(i.e. weld/polish the worn spot) another gear? I'm reluctant to try and find a place where I'm at only because I don't know if they can do the job correctly. Your friend's son has shown he can do the work.

I don't have a time table right now when/if I'll rebuild my tranny like what you did. I'm somewhat mechanically inclined and the work you did didn't seem complex.

Lastly, I was thinking about the wear between the gear and the bearing race. Since the gear has some those two notches on it, I assume for lubrication, I wonder if putting additional notches would help. My thinking is that there will be less surface contact on the bearing race which should be less wear and there will be more lubrication. Comments on this?


Thanks,


Rey

Originally Posted by mark883

Well, after viewing the stool sample from someone else's transmission, and an Internet pissing match, lets get back on track.

Here's my refurbished gear, back from my coworker's kid.



I'd say that looks pretty good. The wear was built back up by TIG welding, then machined nice and smooth and flat. None of the gear face depth was sacrificed, so the bearing is now its original depth away from the gear teeth. If the face is, in fact, now harder, I should get better wear than the 45000 miles now on the bike. I will replace the bearing, mostly to satisfy the slightly OCD control freak behind the handle bars. If the money was a big issue, I wouldn't, but I'll feel better this way.

I hope.

Next up, lets think about 2nd / 3rd gear.

I'll post those thoughts and pics later. Technically, I'm at work.

[mark883]

Originally Posted by reyb

Great thread Mark883. I've been googling recently regarding my 2000 R1100R tranny. Initially, I thought the noise I'm hearing was the throwout bearing but after all the articles I've read it seems that it's the tranny's input shaft. Some questions I have about your tranny rebuild are:

How did you heat up the bearings without melting the seal? I replaced my final drive bearings(big and tapered) and put them in the oven. However, they didn't have a seal, so I'm afraid that if I cook my bearings I'll melt the seal.

I used a sacrificial large toaster oven. You don't need crazy hot, just about 350-375. I think the seals can with stand this. At least mine did. Every junior mechanic needs a sacrificial toaster oven. Especially if you have a wife.

When I replaced my FD bearings, I used a bearing puller I got from Sears. Looking at the tranny input shaft, I'm thinking I would pull the bearings off by grabbing/pulling the gears which would pull the bearing off. Is this what you did?

I used a hydraulic shop press with one of those flat bearing pincher things (Don't know the proper term) I think I did have to grab under the one gear, if I remember right. Just remember to remove all the retainer clips, or you'll be cussing or hurting things. I don't really like bearing pullers, they don't agree with me for some reason- they beat up the end of the shaft. With a press, you just have to be able to catch the shaft when it pops out.


Did you use a press to press on the new bearings? Which the large bearing on my FD, I used the old bearing to hit on(gently) to drive in the new bearing which worked fine.

Warm up that bearing, and while you're doing that, set the shaft out in the January coolness- about 20* or so. You drop the hot bearing right on, and it will set. Since you live in Sandyeggo, you will need to use the freezer. No press is necessary. I'm a bit paranoid about new bearings. Especially expensive BMW bearings. Expand the bearing with heat, shrink the shaft with cold, they'll drop on.



Any chance your friend's son would "rebuild"(i.e. weld/polish the worn spot) another gear? I'm reluctant to try and find a place where I'm at only because I don't know if they can do the job correctly. Your friend's son has shown he can do the work.

That could be explored. However, no guarantees or warranty! But mine is still working- I didn't do a ton of riding this year. But, I don't know why it shouldn't provide good service life.

I don't have a time table right now when/if I'll rebuild my tranny like what you did. I'm somewhat mechanically inclined and the work you did didn't seem complex.

The worst thing is heating up the cases when you put things back together, since the bearings are tight fits in their respective case holes. The WORST is the smaller top cover, which is hot, and you're fighting to get three shafts lined up properly, while hitting the thing on. I used TIG welding gloves. And a mallet.

Lastly, I was thinking about the wear between the gear and the bearing race. Since the gear has some those two notches on it, I assume for lubrication, I wonder if putting additional notches would help. My thinking is that there will be less surface contact on the bearing race which should be less wear and there will be more lubrication. Comments on this?

Beats me. I'm not an engineer. I'm thinking it has more to do with surface area and pressure from that big 'surge' spring in the shaft. My bet, it wouldn't do much good. I think things are doomed to wear with that spring.


Question: Is the 2000 R model still the old 5 speed, or is it a 6 speed? I don't know how things work with a six speed, but maybe the shaft problem is the same. That's the year the GS went 1150/ 6 speed.

I'm trying to think here- but there's not much of a throwout bearing on a GS. Its more of a silly thing at the back of the tranny underneath the lever that connects to the clutch cable. The noise is probably the input shaft- mine wasn't really making much noise, the shifting was just a bit blech. If yours really is grinding, that's not good.

Even if you don't decide to tear into the gearbox, you could remove it yourself and send it to someone like Anton that knows what he's doing.
While you're removing (and putting it back on) your gearbox, give yourself a $100 bill every hour, cause that's what you're saving. That was the worst part of the job, and I particularly hated the battery box / fuel injection spider part of it.

Get yourself the BMW service manual, and read it three times. You will at least need the torque specs. (I may have used three different torque wrenches in the process) Some of the manual was not translated well from the German. You may get confused at times.

Also, if you don't trust your life to your mechanical work, don't do it. Wheels can fall off and stuff, and you could die.

[GmanVic]

Hey Mark! Nice thread, great photos, and inspirational, too. I am working hard to AVOID taking my m97 apart. The input shaft seal is leaking and it seems I need to take it apart to install a new one...can you confirm (or deny) that? And if yes, is it possible to take it apart "minimally?

Cowardly yours,
Gerry
;-)

[mark883]

Originally Posted by GmanVic

Hey Mark! Nice thread, great photos, and inspirational, too. I am working hard to AVOID taking my m97 apart. The input shaft seal is leaking and it seems I need to take it apart to install a new one...can you confirm (or deny) that? And if yes, is it possible to take it apart "minimally?

Cowardly yours,
Gerry
;-)

First you need to know if the rear engine seal or the front trans seal is leaking. If you know its stinky trans oil (dino poopy sulphur), not then gassy used engine oil, then you have the answer. I believe you can replace the front trans seal, the hard part is getting it out of there, then devising a way to drive the new one in around the input shaft. People have used a piece of PVC pipe, but I don't know if you have to turn it down on a lathe to the appropriate diameter. If you look at the pic of mine on the first page, you can see its nice and dry, but the seal is rather recessed in the hole. Could be a bit of fun, both to pull and install.

Worst case, the front of the case is the 'lid' so you could always take that off and do it that way. But I don't think you have to. Either way, wrap the input shaft when you install the seal, so you don't damage it, and have another leaker.

Have fun taking the butt end of your bike apart! Be sure to put it back together correctly too. That's always nice at 85mph or so.

[GmanVic]

Originally Posted by mark883

First you need to know if the rear engine seal or the front trans seal is leaking. If you know its stinky trans oil (dino poopy sulphur), not then gassy used engine oil, then you have the answer. I believe you can replace the front trans seal, the hard part is getting it out of there, then devising a way to drive the new one in around the input shaft. People have used a piece of PVC pipe, but I don't know if you have to turn it down on a lathe to the appropriate diameter. If you look at the pic of mine on the first page, you can see its nice and dry, but the seal is rather recessed in the hole. Could be a bit of fun, both to pull and install.

Worst case, the front of the case is the 'lid' so you could always take that off and do it that way. But I don't think you have to. Either way, wrap the input shaft when you install the seal, so you don't damage it, and have another leaker.

Have fun taking the butt end of your bike apart! Be sure to put it back together correctly too. That's always nice at 85mph or so.

Thanks Mark! Yes. Exactly as you stated. Am putting the bike back together now and confident that it won't leak anymore. The seal was quite recessed and tricky to get out but with a little prying with some dental picks... And yes the piece of PVC pipe as a drift got it back together. Thanks for your help.

[larryboy]

Originally Posted by mark883

The races are hard to see, but I do know what a grindy bearing feels like. This didn't.

Yup, me too. Couldn't see anything wrong, couldn't feel anything and my seal wasn't leaking either. Just didn't trust the damn thing, so I cut the bearing open.

Badda bing, badda bang, bad bad race;




The bad spot was at the top and I couldn't pull on the hub hard enough to feel the bad spot, glad I just took care of it.