Hi everyone,

I have made a very basic mistake.

While changing transmission oil, I failed to follow the procedure of using the spanner as dipstick and hence filled 1.1L of transmission oil into the reservoir.

Coming home from the second trip since the oil change, see attached pictures of the leak. I assume I have overpressured the seal and it has burst.
That said, when draining the oil prior to the oil change, very little was left in the reservoir, so it is possible the seal was weak already. I bought the bike last year, this was my first transmission oil change.

I fear I have a pretty expensive problem on my hands and I am not sure how I should approach this in the most economical way.
Is this fixable or do i need to call give her to a garage ?
Can I drive her ?
About 2 dL of oil has poured out. I don't know how much has been lost while driving as I haven't drained the remaining oil yet.

Any input is highly appreciated.

Best regards,
Einar.

Since 900cc (+ or - 50cc) is required it seems you didn't add so much as to cause catastrophe. Did it simply leak out of the accordion boot at the clutch lever, or push past seals elsewhere? I'd drain off the excess, if still overfilled, and measure to the correct level, clean up the excess, and presumably the back tyre/brakes, and get yourself home.
It's unclear, other than wetness round the boot, where a leak is from the provided pictures.

Nothing to worry about. The transmission has a breather cap on top so it operates at ambient air pressure and can't "overpressure" to blow a seal.

When I purchased a K1100RS the prior owner had had it recently serviced at Ventura BMW where some dipstick techie filled the transmission up to the brim of the filler plug.  I rode it aggressively several hundred miles to friend's house before I checked all of the fluids and got the fluid back down to the right level.  Tens of thousands of miles on the bike since then and no issues.

It may just be that the boot at the back of the pushrod is old and worn out or there's a little too much oil in that..

Money's on a split clutch boot. Additionally, that looks like oil emulsion around the clip, so I'd drop ALL of the transmission oil, check it for water and start again.

Hi everyone,

thank you for the highly useful input, much appreciated.

@TWB : it looks as if the leak is from the accordion boot but I need to dry it all up and check it again as I can't see any immediate cracks in it. I will do as you suggest and refill it to the right level and test again.

@Duck : I was not aware there was a breather valve for the transmission fluid. It is definitely possible the spill is coming from there because, as earlier mentioned, I can't at the moment identify any visible cracks in the accordion boot.

@ Dai : You are right, well spotted, the oil is somewhat "white" in colour so I am wondering as well if there is emulsion or if it is simply dirt from the inside. The old oil that I drained out was dirty and possibly mixed with water. I should know more when I drain it again.

If the adjuster bolt at the back of that boot is too far in the seal around the rear of the boot is not good and it will leak oil.

RicK G wrote:If the adjuster bolt at the back of that boot is too far in the seal around the rear of the boot is not good and it will leak oil.

Hi Rick, thank you for the reply.
I will check that tomorrow first thing.
Is there a specific procedure to adjust that bolt ? I had it in for service at the beginning of the year and they changed the clutch cable. Could that have messed with the seal ?

It has to be correct at 75mm distance of the cable at the end of the actuating arm. If that is correct then check for a split. It is difficult to have an over adjustment on a K75 because the arm will hit the muffler and rattle.

RicK G wrote:It has to be correct at 75mm distance of the cable at the end of the actuating arm. If that is correct then check for a split. It is difficult to have an over adjustment on a K75 because the arm will hit the muffler and rattle.

Great, I will do that. Thank you for the pointer ! 
Much appreciated.

From the BMW shop manual:




Any easy way to hold the clutch arm in place while doing this is to pull in the clutch and place a piece of wood between the clutch arm and exhaust to release the end of the clutch cable for adjusting it.

Good idea to grease the ferule on the end of the clutch cable before reattaching it.

RicK G wrote:If the adjuster bolt at the back of that boot is too far in the seal around the rear of the boot is not good and it will leak oil.

And water can get in if you ride in the rain.

@ Duck : Thank you for that illustration Duck ! Very clear.

If I understand you correctly, in my case it should be a question of properly setting Adjusting Screw (7), as this is the one that can potentially compromise the accordion seal.

The distance relating to the below mentioned 75mm is that not for the clutch cable "slack" and potential clutch plate wear etc.?


@ PSF : Yes you are right, I ride a lot in the rain.  Hence a big concern to see potential emulsion as it does not suggest just an over-pressure situation merely bled off through the breather valve, but rather communication with the environment. Not good.

Yes, that 75mm slack is supposedly only for a brand new clutch plate but I've done it many times with used clutch plates without issue.

It's rare but I've seen it where the tip of the bolt into the boot is not seated/centered properly so you should check that while you fiddling around down there.

Caution: If you let all of the clutch arm pressure off of a used boot there's a spring in the boot that can cause it to tear.

I think the last clutch release arm accordian boot I bought from the dealership set me back about US$30! (23 13 1 338 731) 

Mind the thin 40mm screw clamp is in good nick, too. (23 13 1 241 872)

Two Wheels Better wrote:I think the last clutch release arm accordian boot I bought from the dealership set me back about US$30! (23 13 1 338 731)

That was a long time ago.  The recent price increase added about $4.00, bringing the current price to $46.91.

Someone's pocketing a lot of additional money there; I absolutely refuse to believe that shipping costs make up the difference between U$19.01 (which is what is costs me from Motorworks) and what you guys are paying. If you buy from here, you'll pay U$15.20 plus the shipping (no VAT tax for overseas buyers) and there's no way is the shipping going to be U$20.

Dai, BMW has been doing absolutely bizarre price increases the past couple years.  Some parts have had their price raised 10% and 15% year after year.  I think that in 2016 they did two increases in one year.  I have receipts from 4 and 5 years ago for parts that have had their price nearly double at a time when inflation in the U.S. is less than 2%.

For example, on MAX BMW's official parts fiche, the tank badge was about $16 in 2014, they recently "adjusted" the price on it to $29.22.  If I didn't know better, I'd think they don't want to sell K bike parts anymore.

I sincerely feel bad for anyone trying to restore an old brick today with new factory parts.  So glad my bikes are in good nick and I have a nice stash of used stuff that should last me until I can't ride anymore.

That $30 accordian boot? I pay 5% over actual dealer cost (don't hate me, please) on OEM parts due to a long working relationship with my two local dealers, but am not shielded from their price rises of late. I had to buy a spare chipped, coded key for my K13. These keys used to cost under $50. A few months back I paid nearly $80. Nothing has changed but the price. I don't drop as much coin in there lately.

Dai wrote:Someone's pocketing a lot of additional money there; I absolutely refuse to believe that shipping costs make up the difference between U$19.01 (which is what is costs me from Motorworks) and what you guys are paying. If you buy from here, you'll pay U$15.20 plus the shipping (no VAT tax for overseas buyers) and there's no way is the shipping going to be U$20.

BMW makes a decent markup on parts and then dealers make a huge markup on parts on top of that. It's part of the business model and helps pay for the brick and mortar.

The average markup on OEM parts (from dealer cost to suggested retail)  to dealers from BMWNA is about 32%. 15 years ago it was closer to 40%. OEM are, of course, marked up beyond 'retail' pricing by some dealers, but with the advent of online OEM parts catalogues with published prices those are few and far between. The distributor makes the margin. For the dealers, it's in the aftermarket where margin is made.

An example of this is that for an item a customer pays, say, $100, the dealership has paid BMW $72. If the dealer has got it in for you on the VOR order programme (overnight), BMW tack on an additional 6% to the dealer's cost. But perhaps this is best shifted to another topic as we're running roughshod over the original post.

Hi everyone,

Your continued replies have been really useful for my own understanding as well as troubleshooting of the issue on my bike.

I finally managed to identify the problem, there is a tear in the accordion boot on the upward facing side. I suspect overfilling it has caused it to go from a fracture to an open tear. It also explains the water emulsion.

Next question ; can i fix this (read ; change the accordion boot) myself in my parking garage with standard tools ? Also keeping in mind I would prefer not to mess too much with the clutch cable vs clutch plate adjustments. I'm trying to look for a how-to-guide on how to change it but so far unsuccessful. 

@TWB, some posts transforms into other topics and takes on their own lives, it's one of the things I love about this forum ! And now I already know the reference number and price of the faulty part. Bonus !

What @Duck said on BMW's business model. I frankly find their after service rather ridiculous here in France. It's premium pricing for not even average service.

You can replace it without tearing the bike apart.

Advisable to drain the transmission first but you don't really have to.

Disconnect the clutch cable from the clutch arm.

There's a small hose clamp that attaches the base of the boot to the transmission that you'll need to undo.  You'll need a small regular (flat head) screwdriver to do that.

@ Duck : Awesome ! thanks for the quick reply. Sounds easy enough ! I'll give it a go once I'm back from travels and can source the part. 

HUGE relief for me, as I feared this would be an expensive affair.

It's not THAT easy. Undoing and redoing the tiny screw of that clamp is kind of a pain and will cost you a swear word or two.

But at least it's not an expensive or complicated repair.

Haha fair enough ! And thanks for the warning.

I'll brush up on colourful language before attempting the repair.

I haven't done one in a while but I think the last time I did, once I got the boot seated, I reattached the clutch arm to keep things in place while tightening the clamp as there's a spring inside the boot pushing it out.

Good advice thank you. I will do that.

Also, for anyone reading this thread, if you are ever tempted to use a powerwasher on your K to clean out around the swing arm, you WILL blow the clutch boot off its mounting and get water in the transmission. Chances are you will also put water in the gear position indicator switch.

+1 on what Olaf said.  That is the one part of the k-bike that is better left dirty than clean.

Point-Seven-five wrote:+1 on what Olaf said.  That is the one part of the k-bike that is better left dirty than clean.

There's a TON of road grime that builds up inside the back of K bike transmissions though.

I do agree that pressure washing them is a very BAD idea as I think water can also get in via the breather cap.

However, if I have time when doing a spline lube and have the transmission removed, I usually wash them with engine degreaser (Gunk), a sponge and a garden hose, being careful not to get any water in the breather cap or clutch boot.



I also do the same to the center stand assembly.

Hey guys,

Update on my progress, it is not an especially easy task so far. I hope I'm not in over my head.

I managed to take off the boot and remove the spring with a plyer after much hassle and by tearing apart the accordion boot. See attached picture. 

As you can see I have very little clearance between the clutch arm and the seat of the spring.
To test, I tried to reseat the spring only, and but were unable to do so.

Any advise on how to proceed with the installation of the new boot ?

The main problem I will have is to get the spring into its seat while simultaneously fitting the accordion boot. See attached picture. 

My bike is a K100RS, the clutch arm cannot bend out further as it's touching the exhaust pipe.
Is there an easy way to remove the arm completely that I have failed to identify ?

Your input as always highly appreciated.

Best regards,
Einar.

PS : ref the above discussion on cost, I paid a total of €40.73 for the boot, the spring and the clamp.

Either the muffler is removed, or the muffler and header pipes are removed together, then the side stand retracting rod is removed before removal and installation of that boot is attempted. That allows the clutch arm to swing away from the piston. Just keep your head down, keep moving forward, and get a manual. There are a couple of them downloadable from this site.

Forget about easy or difficult.

While you are doing this do yourself a favour and fit a grease nipple to the clutch arm. Occasional greasing will stop water and road crap from getting in and lengthen the life of your clutch cable. Lubricating your cable with a PTFE based lubricant also helps along with greasing the cable nipples at both ends and the lever pivot points. Some non PTFE based lubricants can degrade the Teflon liner in the cable.
Regards Martin.

@ Laitch : Thanks for the feedback, I will do that then. The reason I'm trying to anticipate the level of complexity is because all I have is a parking garage and standard tools.

@ MartinW : Good tip, I will look into installing one. Anything increasing the lifetime of these critical components is welcome.

Laitch wrote:Either the muffler is removed, or the muffler and header pipes are removed together, then the side stand retracting rod is removed before removal and installation of that boot is attempted. That allows the clutch arm to swing away from the piston. Just keep your head down, keep moving forward, and get a manual. There are a couple of them downloadable from this site.

Forget about easy or difficult.

If you are on a 16v the standard muffler is a one piece so it comes off as one piece. Watch the procedure for refitting [its in the manuals too] it and may be advisable to have new mounting bushes. Lots and lots of WD40 on the header nuts before you go at them.

92KK 84WW Olaf wrote:


If you are on a 16v the standard muffler is a one piece so it comes off as one piece. Watch the procedure for refitting [its in the manuals too] it and may be advisable to have new mounting bushes. Lots and lots of WD40 on the header nuts before you go at them.

Thank you I'll keep that in mind. I'll read up and give it a go tonight and see how far I get.

The photo looks like its got clamps on the headers to muffler connection like on 2v but even with that most remove it as one piece. If you do find you are opening those clamps no problem apart from needing to make sure you line them up as they are jig saw pieces, be sure to get some good photos before you open any of them.

Hi Olaf

It's a 2V and hence not a one-piece as you correctly identified. 

I'll see if I can get it off in one piece. And yes, taking plenty of photos should hopefully help with the reassembly. 

It says in the manual that there are sealing rings that must be changed. Is this strictly necessary ? I would have to order them in that case.

ERasberg wrote: The reason I'm trying to anticipate the level of complexity is because all I have is a parking garage and standard tools.

You might find this video inspiring, regarding constrained work space.

Its a job you can do roadside. The thing is to get lots of the WD40 on the stud nuts and studs .....but unless you have had that off in more recent times it may not be as simple...this is what I do. Before going at the exhaust I have new nuts studs and the sealing rings. The nuts can be split it needed, leaving the studs in, but sometimes the studs come out with the nuts. Having all new makes it easy and quick to put back. Copper paste on the studs before you screw them in. You are likely to end up with a few spare studs but always useful to have them. Now I am on Ks a while I slacken off the nuts and retighten every few months so I know if I have to get the exhaust off I won't have issues.

Watching this with interest because my K100RT needs a new clutch boot fitted. It got one in early 2017 when I did the clutch and rear main seal but its failed.

@ Olaf : Thanks a lot for the encouragement and all the valuable advise. I lack spare studs, bolts and seals so I'll start by dismantling while the order is being processed. 

I'll find out tonight regarding the mechanical integrity of the exhaust. It looked pretty rusty but fingers crossed.

Being a lazy git, my approach would be to undo the muffler mount to the footpeg plate, loosen the clamps where the headers attach to the muffler inlet and angle the muffler down to gain clearance without actually removing it.  If I still need clearance, I'd loosen the nuts at the cylinder head so the headers can be angled down a bit as well.

Hi PSF ; yes I too hope that it will be enough to bend or remove the muffler only.

I have decided to do it in two steps :
Muffler first - bend then remove
Headers second - bend then remove if necessary.

It's a bit more time consuming, but it might be easier for a rookie like me instead of trying to undo it all in one piece knowing the headers probably won't slide out of their seats like pistons.
Whether they can be bent remains to be seen. 

I'll probably be back in a few hours with more questions...bear with me...

On a K100 it is much better to remove the can and the headers as one unit.  Getting the headers lined up and attached to the exhaust can again can be a PITA.

I am totally with Duck on that one.

If you decide to bend the muffler to one side and that's not working for you I think I would bolt it back up again and then remove as one piece. The idea of separating the headers and clamps is well explored and its a real PITA getting it back together.

However, if you do end up with it apart.........POLISH THE DARN HEADERS while you have them off!!!

Hey guys, thanks for the advise. I'll keep that in mind while proceeding (with caution).

Just back from the garage now, and there are two screws too rusty to be removed. One on the muffler cover and one on the foot peg.

For now I have soaked the muffler clamps + screws in WD40 and loosened up the screws I could on the muffler cover and foot peg.

I will need to drill the two remaining screws tomorrow before I can proceed.
Will keep you posted once I get over this hurdle.

Einar/

I honestly think it’s easier to just undo the 8 nuts and 2 bolts and take the complete exhaust off. Getting the silencer lined up and pushed on is a royal pita.

nobbylon wrote:I honestly think it’s easier to just undo the 8 nuts and 2 bolts and take the complete exhaust off. Getting the silencer lined up and pushed on is a royal pita.

Yep. After you've done it once you'll never want to do it again if you can avoid it.  It's one of those things that looks like it should be simple but isn't.

Spray some penetrating fluid on the 8 nuts and leave for an hour or so. Start the bike up to get the studs and nuts hot and using a good quality socket they unscrew easily. Careful not to burn yourself.

That procedure is recommended by Delkovic exhausts for removing the easily-broken studs on a Bandit but they say soak the studs every day for a week first. I'd add; at the end of the week (!) go out and ride it to get it seriously hot and then use a side-drive socket, not a 12-point one. With a side-drive socket you stand far less chance of rounding off the nut. I now only use 12-point sockets when I really have no other choice.