Clutch advise needed.

[DJ Downunder]

Due to being mid Winter down under I just had a few days of not riding due to crappy cold and wet weather...I usually ride almost every day..Yesterday I braved the cold and went for a ride..I found that after a few minutes I had very little clutch..It was like the reach adjuster had moved..I pulled over and fiddled with it but made little difference.

I tried to take off and stalled..and after pumping the clutch I was able to take off ok...I was limping home...feeling the clutch lever coming all the way to the bars without engaging the clutch..I had to keep pumping the clutch to change up and down gears...I was half way home and pulled into a service station to get fuel and buy some clutch fluid (dot4 right?)..thinking that I may have let it get too low.

I opened the clutch reservoir and it seemed pretty full..it also seemed very dark in color (?)..I filled it as much as I could with new fluid and put the cover back on...It made very little difference so I rode home pumping the clutch all the time to keep pressure in the system..I got home ok...I'm no real mechanic but I'm willing to have a go..In the past I have only done oil changes myself..and a service is over due now..btw I also have my bars slightly rotated forward making topping up the clutch fluid a bit tricky because it's not level.

Should I try and fix this problem myself...anyone else experienced it or know what's wrong..maybe I have air in the line..It just seems a coincidence that I have had this problem after not riding for a few days (almost a week)...Thanks for any advice....I was going to just take it to my dealer but I think it's time to learn to fix things myself..besides it's likely to cost heaps and it may be an easy fix..fingers crossed.

DJ

[touchton]

I had the same issue with mine. The clutch slave cylinder had failed. I had to take it to the dealer to be repaired.

[iowabeakster]

bummer DJ.

below is some clutch advice from Cyclerob from another thread. I would try the bubble removal trick first. You defintiely also need a total fluid flush/replacement. If all that doesn't do it?


good luck.


Rob says,

Problems with the clutch fluid are influenced more by the age of the fluid than the odometer reading. Mid window fluid level is OK unless the bike is leaned way over on the sidestand and you jerk the bars while squeezing the clutch lever. That would move the fluid to one side instead of covering the feed hole and inhale a tiny air bubble. That'll give you the symptoms you have. It's a long shot, but for some unlucky people it can and does happen.

There is an easy way to purge a clutch master cylinder air bubble any time the bike is stopped without taking anything apart. It can firm up a soft lever you've gotten used to that still functions OK, but with a tiny trapped air bubble in the banjo bolt fitting or the piston bore itself. It requires you lean the bike to properly orientate the master cylinder so the air bubble's path is up and out the internal bleed-back hole. This technique works on any bike with a clutch master cylinder, with only pullback cruiser handlebars having issues because of the weird way they are tilted. Here's what you do:

1 - Sitting on the bike, grab the front brake to keep the bike from rolling.
2 - Turn the steering full right lock and keep it there.
3 - Lean the bike as far as you can to the right without loosing it.
4 - Squeeze the clutch lever about a quarter of full travel in-and-out about 30 times with a full release pause about 1 second between squeezes. Squeeze in slowly, release it quickly.
5 - After just a few squeezes you should feel a change in firmness and the point of actuation.
6 - Smile bigtime and go for a ride.

Air can also be generated by grungy bacteria growing in the minute amount of water absorbed by the 3 or 4 year old DOT-4 fluid. Engine heat kills this stuff, but a bike in storage or one infrequently ridden is an easy target. Just like the tiny bubbles in beer. This grunge can stay in place on a bleeding operation as a film on the internal walls of the system, usually in the lowest point, the slave cylinder bore. Removing the master cylinder and especially the slave for disassembly and cleaning borderlines on major surgery, so make this a last resort all else has failed choice.

On the scheduled clutch bleed I run thru 3 reservoir fills of fluid once a year and the system stays clean. When bleeding, squeeze the lever to the bar and release the bleeder screw rapidly to aid in removal of stagnant fluid hiding in the corners.
_________________
Member since Sept 10, 2001

Only one who can see the invisible . . .
. . . can do the impossible.

[DJ Downunder]

Thanks guys...touchdown..I was thinking that might be it..

iowabeakster..that may be my problem..I'll give it a go..thanks..

DJ

[Boxer]

Yes it sounds like the slave has gone south. That fluid should not be dark. I bleed mine about every other year and its always still almost clear.

DJ, you will have to take off the bottom end of the rear shock and raise the frame about a half inch to get the slave cylinder to slide out once you undo it. I would do this before I'd haul it to a dealer. Once it's out you can replace it with a new part or clean it good and put it back in, depending on its condition. After its all reassembled and the shock is back on, you just fill it back up with DOT 4 and bleed it out good.

Rob has lots more info on this for sure, but I think the hardest part of this task is getting that bottom shock bolt out. It requires heat since its locktightened in there.

[zooomart]

DJ,
Sorry to hear of your clutch problem, sounds like the same issue I had in May. You probably already checked out the May18th thread. Tranny seal is the likely problem, which sinks because they should last much longer than a few hundred hours of service ( in my case). I still don't believe that Mobil 1 in my tranny contributed to the seal failure.

Share with us what the dealer sez unless you tackle the job yourself. If you do the work yourself... a picture of your hands before clean up.

Good Luck

[boxermania]

DJ

Yep, clutch slave cylinder......the pressure you build starts leaking either out or back to the low pressure side, in the first case the level of the master cyl will go down, not so in the second case. Rebuild or replace.

I recomend changing the clutch and brake fluid every two years, this is based on the high humidity of Louisiana. We do it at the end of the season (since the bike will see less use) and have never experienced any problems. This assumes that you are using the right brake fluid for the application.

[CycleRob]

Wow. The puzzle pieces are forming an answer to this question of why the clutch lever goes soft and dysfunctional. Besides the left HandGuard contacting the lever's ball end preventing it from fully releasing, can we point the finger at Mobil-1?

I had the same dead lever problem about 4 or 5 years ago. The clutch lever progressively went soft and the DOT4 system fluid got smelly and dark. The reservoir was full, dark with Aluminum glitter to it & rankisly smelly. I did a roadside bleed and recovered function. Then it did it again later on in the same ride. It turned out the upward migrating left HandGuard was not allowing the clutch lever to go to full release, somehow overheating the slave fluid to boiling.

I believe I was running Mobil-1 in the transmission back then. I changed out the Mobil-1 the next 6K service because I noticed it did not shift as smoothly as other heavier weight synthetics. I noticed a harsher "sting" of gear dog engagement as I was shifting. I continued to use Mobil-1 GL-5 in the rear drive because of it's low hand-spin rotational friction and noticeably cooler to the touch running temp. No other problems ever happened after the handguard repositioning and trans fluid change, now with 56,090 miles (90,268km].

To think that Mobil-1 swelled or softened the transmission seal(s), as some rumors say, makes me wonder how very right they are. I say "wonder" because no gear oil leaks have ever occurred on my bike.

Getting back to DJ's problem . . . . Being winter there, my advice is for DJ to take the clutch release system all apart for cleaning, diagnostics and selective replacement. Like Boxer said, the frame has to be loosened and lifted a little to get the clutch slave out, but it's not difficult, just simple multi-operation busy work that one person can do using tiedowns. There aren't many individual internal parts to the clutch release system, so erase your fears and dig in. You'll also be able to clean the (removed) rear shock and swingarm area really good. The 69MegaByte PDF file of the BMW manual walks you thru the process, but it does not spoon feed you. Internal snapring pliers are prolly the only special tool you'll need (to take apart the master cylinder and slave).

A few tips: loosen tight banjo bolts before dismounting the slave or M/Cyl. You can contact me and I'm sure Boxer (Phil] & BoxerMania (Al) if you get in a jam. We all have digital cameras, fast net access and (speaking again for Phil & Al) a willingness to help. DJ has lots of crappy cold weather indoor time and a very sick bike.

[Sunbeemer]

DJ - Sounds like air in your clutch line. I'd try bleeding the line and purging the air with new (DOT 4) fluid. It might save you some extra (uneccesary?) work. I bleed mine every year here in humid Florida, but it doesn't look dark, just a little cloudy...

If the clutch fluid level drops, then you've got a leak, because under normal usage, the fluid level in the clutch's master cylinder reservoir rises as the clutch plate wears. If it is leaking, find out where. If it's at the slave cylinder, replace it before it runs onto your clutch because replacing that is a much bigger job

[geothepencil]

the fluid level in the clutch's master cylinder reservoir rises as the clutch plate wears.

I removed some fluid the other day from my 02 RR reservoir as it was completely full. Clear fluid, but full. It actually came out under pressure when I cracked the lid. Everything else seems OK although the clutch engagement is a little abrupt with the lever almost all the way out. (20K) Anything I should be looking for at this point ? Thanks,

geo

[DJ Downunder]

Now my brain hurts... ..jeeez it's all tricky stuff isn't it.. (for me anyway)...Thanks for everyones advise...I tried the air bubble thing without any luck.

Thanks CycleRob...I was at my BMW meeting last night..and talked to a guy that suggested buying a clutch slave cylinder repair kit and fixing it myself..He also suggested buying a speed bleeder.

I know some very good BMW service people that are local..and not a genuine BMW dealer..so they should be cheaper..I'll ask them for a quote..Another option is that our club as a service day every month that I have never been to in the past because I work weekends..It might be time take a day off work and roll up and do it then..The only problem is that the location is a fair way from where I live and I don't like the idea of riding it that far the way it is.

It seems odd to me that I have no leak anywhere (that I can see)..I changed the clutch slave cylinder on my car a few years ago..because it was leaking..It also seems odd that I can go for years without changing the clutch fluid in my car..Why is my bike any different?

I have always had my servicing done at a genuine BMW dealer..and had the clutch and brake fluid changed every two years..I tried to change the clutch fluid myself but need to buy a nipple-thing-a-ma-jig first to attach to the bleed point first..I don't know why BMW don't have one there to start with..and I will look into buying a speed-bleeder kit also.

Mean while..I guess I'm grounded...

DJ

[CycleRob]

..It also seems odd that I can go for years without changing the clutch fluid in my car..Why is my bike any different?

Hmmmmm. I had to think about that because I know it is absolutely true and the answer wasn't obvious. Adding to the dilemma is the fact that the car's system also has DOT-3 fluid which is slightly inferior to DOT-4. Then I mentally took both systems apart to figure out why.
The slave on your car has a piston about 1/4th the diameter of our bikes slave piston -and- the car slave is hanging out in the cooling breeze. The bike's slave is buried inside the air cooled transmission that sometimes operates well over the operating temp of a car's water cooled engine/trans assembly. Most importantly, the car's slave and master cylinder pistons have high quality, tight fitting, rubber bellows totally isolating the moving pistons completely from the area outside them. The car's master cylinder boot is under the dash that is protected by the environmentally controlled cabin where the people are. Also, the car's master cylinder heats up from the engine at about the same rate and temp as it's slave at the other end, while the bike's master cylinder gets cooler, sometimes in the rain or snow, as it's slave heats up, worst case, 200 degF hotter. Lastly, the bike also will experience off season idle periods as long as 4 months by an occasional rider in frigid climates. Doing the math, it' easier for me to see now why the car's less exposed to moisture and temp swings hydraulic clutch release system needs less attention.

That reminds me . . . . it's time (again) to purge and replace the DOT-3 clutch fluids on my `98 truck and her `04 car. Taking the slave pistons out on them for cleaning is so easy compared to my bike. It's been way too long.

Sounds good to me.

[DJ Downunder]

Thanks Rob...it's a shame that BMW don't have the clutch slave cylinder externally mounted like in my car..btw...I popped into my local BMW service shop today..I have it booked in for next Monday.

Chris who is the boss there is a nice guy and I don't think they will rip me off..and will do a good job.

He had one there that they were in the middle of doing (a clutch on an 1150 RT cop bike) and he showed me..He said once there is a leak in the slave cylinder the contaminates (oil etc) on the other side can flow back up the line and make the clutch fluid dark.

Because there is no visible leak and once the clutch fluid leaks around the cylinder it can work its way along the shaft to the other side and into the clutch..that's bad.

They do a small mod to the slave cylinder gasket..they cut a very small slot at the bottom to lets any fluid that passes past the piston to drip out..to give a tell-tale that somethings wrong..and help stop the fluid getting through to the clutch.

It seems like a good idea.

My service is due so they will do that as well..including a new alternator belt..because it is also due (60,000 klms)..fingers crossed that they don't find other things wrong..I hate large bill surprises...So this time next week I should be back on the road..and my wallet will be a little lighter.

Maybe I will get MIXR's cam chain tensioner mod done as well..They didn't know anything about that..Anyone remember these part numbers.

DJ

[Sunbeemer]

Left cylinder Cam Chain Tensioner Upgrade Parts:
11 31 7 688 629 = cyl. tensioner
11 31 7 656 922 = piston
07 119 963 308 = gasket ring (for new cyl. tensioner)
13 54 1 341 797 = TBI o-ring (if you need to remove the left throttle body and find the o-ring damaged)

AND, the BMW clutch bleeder screw is part #34 21 2 330 310,
OR the Speed Bleeder for bleeding the clutch (at the filler adapter) is # SB1010S

[DJ Downunder]

Thanks Rich..

DJ

[baltm604]

DJ,

You do not need to remove the TB. There are prior posts around here that show how to do it with a 3/8" rachet, a 15mm and 17mm socket and wobble adapter and a 3" rachet extension.

That and a piece of wire or magnet to fish out the old piston, it took about 10 minutes in my driveway to do.

Bill

[wncbmw]

Not to hijack the thread but what's up with Mobil 1 rumors for the tranny?!? First I have heard of that! And I am on my 2nd change with Mobil 1! Any substance to this?

BTW, hope you get back on the road DJ without too much pain ($$)!

[def38]

Not to hijack the thread but what's up with Mobil 1 rumors for the tranny?!? First I have heard of that! And I am on my 2nd change with Mobil 1! Any substance to this?

Mobil, Shell, Texaco, BP...name brand gear oils of proper grade and viscosity are all good choices.

Personally, I run 75W-140 synthetic in the transmission. Also, I ad 10% moly to both transmission and FD gear oil.

[DJ Downunder]

I'm back on the road again.. ....Here's an update for those that are interested.

Last Monday I had a new clutch slave cylinder fitted..btw..I've had my bike since 01 and ride almost every day..all year round.

I think because I ride mostly in city traffic I use the clutch more often than some would..so I guess 60,000klms and 6yrs is not too bad.

Here's a pic of my old slave cylinder...



Check out the crud and gunk..Because the brake/clutch fluid had leaked to the other side of the piston and mixed with the bearing grease it made this mess..btw I'm lucky that the fluid had not made its way to the clutch plate because that would mean replacing the whole clutch.

The service guy told me that what saved the clutch was that BMW now have a felt washer to stop the fluid leaking through..but it will still get through after a while..He said they used to do this on the older BMW's and was a good idea..but they stopped doing it on the 1100's..and if it had been one of them the clutch would be stuffed instantly..Lucky for me BMW went back to the felt washer with my bike.

Here's my new clutch slave cylinder fitted...Notice the number stamped onto it...#20.



This pic shows the nifty trick that they do..They cut a small slot in the bottom of the gasket that will allow fluid to drip out if the slave cylinder starts to leak..and give a tell-tail sign that it needs replacing before any damage is done.



The one that came off has a different number on it..#24...the one that they fitted is the wrong one #20..it's from a K bike but still fits and looks the same..But you need forarms like Popeye the sailor man to pull the clutch...BMW had packaged them wrong so I will need to take it back and have it swapped over once they get the correct one in...It's something to watch out for if any of you guys do this...The #20 has a smaller internal diameter and needs more force to operate it..They look the same on the outside.

Here's some more pics..here's my old one with the gunk..before and after cleaned off.



[

Here is the cylinder apart...Guys love to take stuff apart to see what's inside don't we..

Maybe all it needed was a new rubber seal for the piston..but BMW only sell the whole thing.

DJ

[def38]

Here is the cylinder apart...Guys love to take stuff apart to see what's inside don't we..

Maybe all it needed was a new rubber seal for the piston..but BMW only sell the whole thing.

DJ

I note from the photo that there is a rubber seal showing in one groove. Was there evidence of a rubber seal in the other empty groove?

Also, what is that big ball bearing assembly in the previous photo?