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97 RT revving but not accelerating right, in all gears, > about 3000rpm


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I've had my RT going on 1 1/2 years and it has 47k miles on it now. This problem started recently. If I accelerate slowly, the problem isn't noticeable. When I accelerate more aggressive, the RPMs go up as quickly as you would expect, but the bike barely accelerates. This happens in all gears. Shifting is still smooth and everything feels ok with the clutch. No noises or vibrations.


The only problem I've had so far is with the (piece of junk) Remus muffler, the rivets all came out of the front of the can. I re-riveted all of them and it's no longer loose, but I'm not convinced everything is 100 percent with it, since it is still noisier than it was.


I mention the exhaust just to not leave anything out, but I suspect I have a bigger problem that is causing what I described above. I lost my job and won't be able to fix it right away, but if you guys could help me with ideas about what it might be, I'd appreciate it.

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Increased revs resulitng without power applied to the drive line is usually indicative of a slipping clutch.


Check all adjustments first. Worst case senario is a oiled clutch disc resulting from a breached main seal.

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OK thanks. Can I count on this getting worse quickly, or is it hard to say? Like I said, I am out of work and we only have one vehicle, that is currently also giving us problems. I'm hoping the RT can limp along for a few month.


EDIT: Stupid reply. If it's the rear main or anything like that, I know it can get bad real quick.

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Main seal leak...It wont limp long at all, don't try it. You are already stuck under 3k in all gears. It's done.


Do the work yourself and it can be done on the cheap.

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It goes up as high in the RPMs as I want it to, or at least up to 5k, haven't tried higher- just not very fast. It just takes it's time getting there. I'm not noticing any leak, or any smells. I'll go inspect closer tomorrow to see what I can find. Definitely not doubting the possibility/probability of that being what's wrong.

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First thing to check is for free play at the clutch lever on the handlebars. You should be able to pull the clutch lever in about 7mm (measured at the pivot point of the lever on the handlebars) before the clutch starts to disengage.


If you can't get enough adjustment from the adjuster at the handlebars, there is another adjuster at the other end of the cable, that is a little harder to get at.


If the clutch is adjusted properly, then you may have a oil leak on one of the input shaft seals on the gearbox. Removing the rearwheel swingarm and the clutch cable mechanism will show whether or not the piston and pushrod are wet with tranny oil. The oil can travel up the pushrod.


Also, if you remove the starting motor, you can look up inside the clutch cavity with a flashlight and see if the clutch plates have been flinging oil around.


Is the clutch hard to pull or sticky? Has the gearbox been especially hard to shift? You may need to lubricate the splines on the gearbox input shaft. If they dry out, the clutch can hang up and the gearbox becomes difficult to shift.


My clutch was done at 60k miles. They typically last longer than that.

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"First thing to check is for free play at the clutch lever on the handlebars."


I loosened the one closest to the handlebar a few turns, and then tightened the other one a few turns, and that made a huge difference, if not getting rid of it altogether. I will have to test it a little more tomorrow to see, but it seems like this is what's wrong.


If it is something this simple, I am going to be pretty embarrassed.

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i have had some similar issues and i had a thread about it.


my clutch lever is adjusted all the way in and it still slips a little...im sure i need to adjust the lower adjuster on the trans arm.


how much of my tupperware do i need to remove to get to that? and what side of the bike plastic do i need to remove to access the clutch arm if it is not all of it i need to remove...


i have a service manual, but it shows the adjuster and specs, but not all of the steps to get there...just want a starting point to get to the adjuster


sorry for the hi jack but it is related and may help Hydrilla as well

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The important issue on slipping clutches is to have some freeplay at the handlebar. Ideally you want to have the cable adjusted within specs, but if you have free play and the clutch is slipping then you probably have a clutch problem.


To adjust the clutch at the rear of the transmission you will need to remove the left foot rest holder plate. This gives you the opportunity to clean, lube, and adjust the linkage. You do not need to remove any plastic.


At the handlebar insure that the adjuster and the lock ring have 10 mm of distance between them on the threaded piece.


Use a 13 mm wrench on the lock nut on the adjuster on the rear of the transmission and loosen it. Use a 10 mm long 1/4" socket with a 1" extension and adjust the bolt until you have the 5-7 mm of freeplay on the lever at the handlebar. Once you have the proper gap at the hand lever, tighten the lock nut and recheck. Reconnect the plate and make sure that the linkage is working well and that the the clutch lever (where the foot shifts) is centered in the slot.

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Edgar, you are my new friend...that is the info i was looking for!


now i will go and try that. My adjuster at the handlebar lever is adjusted all the way in and i dont have enough free play so i know it is the other end at the trans....or hopefully NOT a T/O bearing issue, but i doubt that at 15k miles unless someone rode it with the clutch mis-adjusted for a long period of time

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Clutch slipping due to lack of free play could result in glazing of the clutch plates due to slipping and overheating. You may have to be a bit rough on the clutch for a while, dumping the clutch without letting it slip too much and heat up, to try to remove the glazing. If glazed, it may improve with regular use over time, or it may not.


Adjust the clutch at the handlebars to the recommended specification - 7mm (it says 3 to 5mm in the owners manual, but that was later revisted by BMW). The place to measure the gap is depicted on page 30 of my Rider's Manual. If you can achieve 7mm adjustment at the handlebars, you don't need to adjust at the bottom end of the cable.

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To adjust the clutch at the rear of the transmission you will need to remove the left foot rest holder plate. This gives you the opportunity to clean, lube, and adjust the linkage. You do not need to remove any plastic....


Use a 13 mm wrench on the lock nut on the adjuster on the rear of the transmission and loosen it. Use a 10 mm long 1/4" socket with a 1" extension and adjust the bolt until you have the 5-7 mm of freeplay on the lever at the handlebar. Once you have the proper gap at the hand lever, tighten the lock nut and recheck....

If you have small hands, it's possible to get in there without removing anything but the black side covers. I use a cut-down deep 13mm socket with a palm ratchet ($4 at Harbor Freight); this just fits between the shock spring and the clutch lever. For me, no combination of extensions and flex joints allowed me to get a regular socket on the adjuster bolt. You still need a spanner to loosen/tighten the lock nut. Once the rear play is correct, it's a matter of feel for the front; for my (somewhat small) hands, I like a lot of free play, so that the clutch starts engaging just off the grip. As long as the clutch isn't dragging when the lever is pulled in, more free play is generally better than less.




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i cant get 7mm at the lever and it is adjusted all the way so the other end needs some loosening


as for the "need to be a bit rough on the clutch for a while"

not an issue, i raced MX for 40 years and a bit of Road racing.

even tho i now ride the nice smooth bmw rt, i still find myself HAMMERING it pretty often....cant teach an old dog new tricks i guess

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  • 4 months later...

Time flies when you have to change jobs again, and you have an unusually cold Winter for North Carolina and aren't motivated to get the bike out.


Today I finally took the right side plastic off, and inspected the clutch cable. It wasn't frayed or anything, so I tightened the cable on that end. When I put everything back together for a test ride, once again there was an improvement but the problem isn't gone. I can gun it and get up to over 4k RPMs before I notice any sort of symptoms, which at that point it acts like before although not as much.


Does it make sense that the cable might just need to be replaced? I know I asked this before. What else would make you need to adjust the cable like this? I think I'd like to start doing more myself instead of taking it to the shop for everything.

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If your clutch cable is adjusted to give 7mm of free play at the clutch lever, as per page 30 of your Rider's Manual (the manual may state 3 to 5mm, but that was revised to 7mm later by BMW) and it is working smoothly, then, in all likelyhood, you need a clutch replacement.


Remove the left-side plastic, remove the left footpeg bracket and remove the starting motor. Take a look up inside the cavity and measure the remaining clutch plate friction material, and look for signs of an oil leak.

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Thanks, I'll check it out in the next few days, by the weekend at the latest. Do you think this is a reasonable DIY job if it turns out to be the clutch? Does it need very many specialized tools? I haven't looked it up yet. I'm not afraid to try things and I usually do pretty well, as long as the risk isn't too high and there aren't too many potential 'gotchas'.


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This was the first job that I tackled as a new (old) BMW owner. It is a fairly major job. You have to split the bike in half to change the clutch. It requires a good set of metric tools (sockets and allen key sockets) as well as a heat gun to soften the locktite on certain nuts and bolts.


If you are generally familiar with automotive maintenance and are comfortable with taking on a fairly major project, then this is a good opportunity to learn by doing and to take a look at a number of other wear areas on your bike (such as spline wear, seal leaks, pivot bearings, rear rotor wear, etc.).


I recommend a good manual such as the Haynes BMW R850 & 1100 93 - 97 manual.


There is lots of great information in this forum and lots of good advice (for example, you don't really need to fully remove the rear sub-frame, with some preparation, you can rotate it out of the way (lift the tail) to get access to pull the gearbox.


It's doable if you are so inclined. Here's what your bike would look like before the gearbox and driveline are removed:





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Thanks for the picture. Most of my experience has been on Japanese V-twins, but I think I could handle it if the manuals/forum write-ups are clear in both the steps and in the parts and tools you need. I'm going to keep this bike for a long time, so it makes sense that I should learn as much about it as I am able. I think I have the manual you mentioned, not positive though.

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Thanks ....I think I could handle it if the manuals/forum write-ups are clear in both the steps and in the parts and tools you need. ......

Well, you are in the right place for help on this forum.

I think that if we wanted to, there are that many pictures around that almost every job could be tackled as walkthrough's, but the clutch change already has been well & clearly documented. So, go for it, and remember to mak notes ant take pictures if you are at all uncertain of assembly.


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Bruce (Bedford)

Watch-ya Hydrilla

Bin there & got the tee shirt.

I KNEW that there was a problem, same symptoms as you but more discrete, my friends rode my bike but didn't agree. However I went through all the cable adjustments as you have been told and yes there was a little improvement.

Then I bit the bullet and changed the clutch - just the plate - like you money is tight.

I got a seal too but as there was no evidence of leakage I didn't fit it on the "if it ain’t broke" basis.

EVERYONE here was sooo helpful and encouraging (thanks fellahs) I did the job, pretty well the biggest one can do on an R1100RT in the conservatory over Christmas (thanks to my wife for helping t lift the g/box-rear wheel assy!!!)

I found that my clutch plate was down to the rivets on one side and nearly so on the other but the solid plates and splines were ok.

BMW quote 2 days, I took 4 but wasn't rushed - you do need space though, if money is tight forget the Haynes manual (its not THAT good) but the on-line Repair Manuel pdf is vital.

You can do it, keep the pics coming we are all with you!!!!



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Just one follow-up note, if you find that you are down to the rivets on the clutch friction plate (I think that's just under 5mm) you should consider changing out the pressure plates also. I was told that the pressure plates wear in a non-uniform, conical fashion. So if you only change the friction plate, it may wear prematurely due to uneven loading, shortening its life. Best to bite the bullet and change out the entire assembly.

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Bruce (Bedford)

Very true NonComp, my clutch plate was to the rivets on one side BUT not yet wearing the rivets - it was on the cusp! (A picture here would be good!)

I inspected the pressure plates VERY carefully there were no fine cracks, no heat spots, no ridging etc. all good common sense auto-engineering so I was happy - unfortunatly I hadn't heard about conical wear or I'd have put a square against them - but hey ho that's the beauty of this forum; every day, every post a new lesson.

Accepted the entire assy would be the safest option but when money is tight you have to make tough decisions & Hydrilla, like me at the moment, is making everything go as far as possible but the good times will come back, life is tidal it comes in then goes out ~ then hopefully comes back in again!


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It does come down to how long you intend to keep the bike too. If you think you may want to put another 60K miles on it, then you might want to change the whole assembly.

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Good feedback and questions both. I do plan to keep this bike for as long as it makes sense, quite a few years hopefully. Based on that, I would like to replace everything that would make sense while I'm in there. It isn't something I'm going to rush into, and I would like to put a parts list together and get an estimated idea of what the total cost will be. I am hoping for minimal down time (as in not weeks) so I would like to have everything or most everything already purchased before I start. I appreciate everyone's support.


One more question- it is perfectly drivable now, and the problem really isn't even all that bad yet- barely noticeable unless I accelerate aggressively. If I end up needing to drive it a while until I collect everything (the wife and I have one other vehicle, the RT is my commuter car), what am I risking damaging other than the clutch? Is there a risk to anything else, like the tranny?

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I think the worst case is that the rivets in the friction disk will damage the pressure plates. But if you are replacing the pressure plates, then no worries there.


So, it comes down to drivability and the risk that you might get stranded somewhere when if finally goes.

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Bruce (Bedford)

This is the order I placed with Motorworks UK just before Christmas '10 to do my clutch:-

Crank seal rear (R850/R1100/R1150/Cruiser)ENA41087 1 @ 15.3

Clutch bolt (R850/R1100 with cable operation) CLA54417 6 @ 0.98

Clutch friction plate (R850/1100 with cable operation)CLA25351 1 @ 66.98

Clutch diaphragm spring standard (R850/1100 with cable operation) CLA42353 1 @ 24.68

Delivery 6.90

Total 119.74 English pounds

Oh yes I forgot the flywheel bolts ENA41472 that had to be added later!

As it was I didn't use the seal or flywheel bolts.

Check to make sure my 1100rt '96 and yours are the same!!!


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Remember Motorworks sadly do not ship to the USA.


PS MotoBins do ship to the US I believe, but it MUST be cheaper buying at home (your home - note mine)!

CLUTCH FRICTION PLATE ALL R850/R1100 - Part No.30525 - £63.00


CLUTCH DIAPHRAGM SPRING- ALL R850/R1100 - Part No.32020 £21.50

CLUTCH BOLT *QTY 6 REQ* R850/R1100 - Part No.32330 - £0.90 ea

CLUTCH BOLT WASHER (6 REQD) ALL R850/1100 - Part No.32360 - £0.30ea

CLUTCH THRUST PISTON ALL R850/R1100 - Part No.31821 £34.00

CLUTCH PRESSURE RING ALL R850/R1100 - Part No.32240 £64.00


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...As it was I didn't use the seal or flywheel bolts.

Check to make sure my 1100rt '96 and yours are the same!!!



Did you get a new Clutch thrust piston BMW part number 23131464167?

I believe Keith (OoPEZoO ) found he needed to becuase it failed shortly after a clutch change.

See post http://bmwsporttouring.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=610130&Searchpage=1&Main=55059&Words=%2Bclutch%2Bpiston%2B&Search=true#Post610130


and entry #614150



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