• Welcome, Guest! We hope you enjoy the excellent technical knowledge, event information and discussions that the BMW MOA forum provides. Some forum content will be hidden from you if you remain logged out. If you want to view all content, please click the 'Log in' button above and enter your BMW MOA username and password.

    If you are not an MOA member, why not take the time to join the club, so you can enjoy posting on the forum, the BMW Owners News magazine, and all of the discounts and benefits the BMW MOA offers?

Zen & The Art of BMW Motorcycle Maintenance: ‘02 R1150RT Clutch Slave Cylinder and Gear Position Switch Replacement

tangoalpha

Member
Well…well…well, it’s been quite a weekend for me and my beloved Der Beemer. Since I just got my bike titled/registered in Texas on Friday and it’s all cleaned up and looking spiffy, I had hoped that I would be able to enjoy a short ride over the weekend.

As I had mentioned in my prior post the bike has been sitting since moving to Texas a year ago, so I wanted to flush the old gas out. Fortunately, I did use a fuel stabilizer and I have have been going out to the garage every couple of weeks to start the bike and let it warm up until I get 1 or 2 bars on the RID display. The bike has sat while on a battery tender so the battery is still in good shape and start ups haven’t posed any problems. So, I took a ride down the street to fill up my tank with premium and that is when I observed (twice) while stopped that the bike didn’t shift from N to 1st when prompted with the clutch lever in. After releasing the clutch lever and reattempting, the bike then shifted from N to 1st gear. Upon returning to my garage, I checked the clutch fluid level by peering through the sight window. That’s when I observed that my “clutch fluid” (also known as DOT 4 Brake Fluid to the rest of the motorcycle riding public) was low.

This of course, led to a discussion here on the forum about why my fluid level dropped and the likely cause being a clutch slave cylinder that needs replacing ASAP. At this point, I ordered a Speed Bleeder to replace the factory grub screw since I’m obviously going to be flushing out the entire system when replacing that slave cylinder. So at this point, now with a full tank of gas and a slave cylinder replacement on my list, I decided I’ll just top off the fluid to the correct level and take a quick spin to see if there’s any difference when shifting from N to 1st. After riding about 20 miles, I noticed a new problem develop.

When riding, I noticed that as I was downshifting in to 3rd gear my RID Display showed E (6th gear). On the ‘02 RT, BMW decided to program the RID to show 6th gear as “E” for economy. As in fuel economy. Because….well, why not? They’re BMW after all and they just had to be different. As I continued to downshift, the RID registered 3rd gear as I clicked in to 1st gear. The green N light is illuminated correctly when in neutral, but it seems that 1st gear and 3rd gears are reading incorrectly on the RID display. So it appears that Der Beemer has learned a new trick! Lucky me. This happened for the rest of the ride home. Besides a faulty gear position indicator switch, I cannot think of anything else that would be causing this.

I decided to consult my service manual and check YouTube for a helpful video on replacing the gear position indicator switch and found a video posted by another Oilhead RT owner who demonstrated how to do exactly that. The video began with “After removing the swing arm……” 😞 -heavy sigh-

So, it would appear that either way, l’m going to be removing that swingarm and disassembling half the bike to replace BOTH the clutch slave cylinder and gear position indicator switch. Desperately looking to turn a negative in to a positive, the only plus that I can see is that I discovered the faulty gear position switch now, so that I can replace it at the same time as the slave cylinder while the bike will be torn down.

Also, while I’m in there performing surgery, I might as well add lubing the final drive gear spline to that list. Is there anything else that you can think of that I should address from a preventative maintenance standpoint, since I’m going in to the bowels of Der Beemer?

- Clutch slave cylinder replacement
- Gear position indicator switch replacement
- Lubricate final drive spine
- ?
- ?
 
I only want to add that disappearing clutch fluid probably means the fluid has transferred into the tranny and forward, on its way to soiling the clutch. Best confirm and get that slave changed out ASAP.
Rick
former owner '02 RT
 
Thanks for your insight. This is definitely on my priority list. Hoping that it’s not already too late. If the clutch were to become soiled, what signs would indicate that? Would the clutch slip or become grabby?
 
Thanks for your insight. This is definitely on my priority list. Hoping that it’s not already too late. If the clutch were to become soiled, what signs would indicate that? Would the clutch slip or become grabby?
Clutch slippage at an advanced-stage, brought on by intermediate-stage leaking of gear lube when the brake fluid damages the front seal on the trans. That usually shows up first as drippage on the exhaust collector and/or oily spooge building up on the bottom of the trans or along the seam lines. But that spooge symptom can also come from a sloppy oil change or leaking oil filter. A thorough wash then a ride before the project starts gives you a cleaner project and sometimes a little added diagnostic info.

Best,
DeVern
 
That gear position indicator switch is about $185.... "Maybe" it can be R&R'd without pulling the bike apart?
It sounds like perhaps its innards are gunked up with a combination of oil and road dirt - can you reach it with a spray of degreaser/contact cleaner?
"Sometimes" the E is due to a bad ground wire.
 
Clutch slippage at an advanced-stage, brought on by intermediate-stage leaking of gear lube when the brake fluid damages the front seal on the trans. That usually shows up first as drippage on the exhaust collector and/or oily spooge building up on the bottom of the trans or along the seam lines. But that spooge symptom can also come from a sloppy oil change or leaking oil filter. A thorough wash then a ride before the project starts gives you a cleaner project and sometimes a little added diagnostic info.

Best,
DeVern
DaVern, I think the reality is beginning to set in of what I may be seriously up against. The feelings of dread are setting in. I totally agree your point about doing a thorough cleaning. I hate working on dirty engines or anything mechanical that has gunk caked on. I never let it get to that point though. Dirt or gunk can also fall in to places it shouldn’t be and that’s reason enough to clean the area before starting work. One thing I will say about my bike, these issues aside, it’s probably one of the cleanest looking 1150 RT’s still around. I get loads of compliments from other riders who recognize that I’m riding a 22 year old machine. I definitely have an attachment to this bike and because I’ve invested so much learning about it, repairing it, servicing it, I’ve grown even more fond of it.
That gear position indicator switch is about $185.... "Maybe" it can be R&R'd without pulling the bike apart?
It sounds like perhaps its innards are gunked up with a combination of oil and road dirt - can you reach it with a spray of degreaser/contact cleaner?
"Sometimes" the E is due to a bad ground wire.
Hmmm…I’ll have to see if I can reach it. From what I imagine, it would seem like I would at least need the rear wheel removed and get the bike high enough off the ground to be able to reach it. I like the way you think. Just not sure I can reach the part without removing the swing arm. I’ll look in to it.
My money (0.02cts) is on having to split the bike and redo all of the components... Main oil seal, clutch plate and slave cylinder.. The bike is old enough to have things aging out. The main seal being one of them.. JMHO YMMV...
Yes, this is exactly what I’m thinking and fear the most. What if the clutch plate is a ticking time bomb and after replacing the slave cylinder, gear position sensor and getting the bike back together that the clutch plate completely bites the dust? Or the main seal? It’s easy to talk oneself in to preventative maintenance, but as you pointed out the bike is 22 years old so parts are aging out.
 
You haven’t mentioned how many miles are on the bike, as that is a factor to consider. If this isn’t a high-mileage bike my personal approach would be to replace the slave cylinder using the method Paul Glaves outlined then ride the bike for a while and see what, if anything, develops.

While you’re replacing the slave cylinder it’s a good idea to provide a drain opportunity so that if the slave leaks in the future the brake fluid can drain away and not pool until it reaches the level of the pushrod and follows it forward. You can either drill a 2-3mm hole in the bottom of the bore the slave fits into, or use a small triangular file to file a v-notch in the bottom outer lip of that bore, so that even with the slave fitted there is an opening to drain leaking brake fluid.

Best,
DeVern
 
You haven’t mentioned how many miles are on the bike, as that is a factor to consider. If this isn’t a high-mileage bike my personal approach would be to replace the slave cylinder using the method Paul Glaves outlined then ride the bike for a while and see what, if anything, develops.

While you’re replacing the slave cylinder it’s a good idea to provide a drain opportunity so that if the slave leaks in the future the brake fluid can drain away and not pool until it reaches the level of the pushrod and follows it forward. You can either drill a 2-3mm hole in the bottom of the bore the slave fits into, or use a small triangular file to file a v-notch in the bottom outer lip of that bore, so that even with the slave fitted there is an opening to drain leaking brake fluid.

Best,
DeVern
I agree with DeVern
Devern, the bike is not a high mileage machine by any means. I’m almost embarrassed to tell you, but it has less than 32,000 original miles on it. The bike was a garage queen when I bought it from a Dentist from the Bay Area. As I understand the story, this bike (Der Beemer) was an identical twin which he kept at his vacation house (spare bike). The other bike was his primary. When I bought Der Beemer in 2016, the bike only had 12,000 - 15,000 miles on it which was one of three bikes I owned at the time. In the 8 years I’ve owned it, I’ve only added another 17-20k miles. Since moving to Texas, this is now the only bike I own. The others have been sold.

I like your idea about using a small triangular file to notch the bottom of the bore. That makes sense. If I can channel my inner Paul Glaves, I’ll see if I can wrangle that slave cylinder and gear position sensor out without removing the swingarm. That would be ideal. I think that settles it. I will start there and see how it goes. I pray that it works and I don’t have to go any further with it.

You guys always have the best advice. I sure am grateful for all your wisdom.
 
Quick update: My project has been temporarily put on hold, due to my garage door spring snapping. Murphy’s Law! I will get that rectified this weekend so I can start working on Der Beemer. I’m using the online fiche available through Max BMW and getting my parts list together and pricing everything out. It dawned on me that while I have the bike apart for this project, I should replace the clutch line that runs from the reservoir to the slave cylinder. Further, I’m beginning to wonder if part of the problem I’m having could be due to the rubber clutch line deteriorating from within. A few years ago, I swapped out the brake lines for a a quality set of braided stainless steel lines from Speigler. However, I didn’t touch that rubber clutch hose. Do you suppose that pieces of rubber may have deteriorated and made its way down to the slave cylinder, thereby gumming up the operation of the clutch push rod? The more I think about it, with roughly 32k miles on the clutch and the factory clutch line/hose still in place I am beginning to think this may be the source of my problem.

What say you?
 

Attachments

  • image.jpg
    image.jpg
    990.2 KB · Views: 2
"Maybe." Interesting idea, but I haven't seen one (for bikes) commercially available... until just now...
Keep in mind that the clutch fluid does not have to deal with the extreme temperatures and pressures that the brake lines do.
You'd probably have to order up a custom line, or have it fabbed locally, providing the correct parts.
Here are three possibilities -
https://www.galferusa.com/shop/moto...draulic-clutch-line-clutch-lines-fk003d407cl/
 
Last edited:
"Maybe." Interesting idea, but I haven't seen one (for bikes) commercially available... until just now...
Keep in mind that the clutch fluid does not have to deal with the extreme temperatures and pressures that the brake lines do.
You'd probably have to order up a custom line, or have it fabbed locally, providing the correct parts.
Here are three possibilities -
https://www.galferusa.com/shop/moto...draulic-clutch-line-clutch-lines-fk003d407cl/
Thank you very much for sending those links. I appreciate it very much. Both of those appear to be very good options. Looks like there’s also a third option. I checked Spiegler’s website and they make a set for my bike.

Your point about about the clutch fluid not being subjected to the extreme heat and pressure is well taken. I guess my only real reason for considering this option is that the clutch fluid uses DOT 4 brake fluid. When I bought the bike, I was encouraged to replace the rubber brake hoses with stainless steel lines as the DOT 4 will eventually break down the rubber inside the hoses, which can lead to brake failure. Given that my bike is 22 years old and that I have no record or receipts from the prior owner which show that the clutch line has ever been replaced, it occurred to me that I should probably do it. Not that I’m looking to add any more expense, mind you.

Speaking of expense, according to the MaxBMW website that clutch slave cylinder sells for $290. Yikes! 😳 What’s even more surprising is that the factory rubber brake hose/line that runs from the reservoir to the slave cylinder sells for $257. Not to mention the gear position indicator switch that also needs to be replaced at a cost of $184. Those prices are outrageous! At least I can save some money on the clutch hose/line by going with one of the aftermarket options. For comparison, the Spiegler clutch line sells for only $70 The factory BMW clutch line, as noted above, sells for 4X more than the cost of the Speigler unit.

https://spieglerusa.com/bmw-r-1150-rt-clutch-line-kit-r-1150-rt-s-bm0173.html

1714475015931.jpeg
 
Last edited:
Paging any and all mechanics:
So now I'm wondering - did the factory make these clutch lines of the same materials as the brake lines?
If they recognized the reduced stress on the clutch fluid, did they use a cost-cutting lining, or just stick with brake hose line? Anybody know?
My bike is 20 years old and has had one clutch replacement, plus many fluid flushes (love that fitting on the end of the hose), and I've never had an issue with clutch actuation and I've never noticed bitso'crap in the old fluid.
So is this something that all of us Oilhead riders should seriously consider?

May 02 - So far, two guys have said they've never seen a bad clutch hose on an Oilhead (I didn't ask about other bikes or manufacturers), but they have seen seeping fittings and slave cylinder seals; also, if they saw junk in the flush, it was always due to a seal.
One said that the swap "probably" wouldn't change the feel of the clutch, first because hydraulics pretty much hide what's happening down there anyway, and second because the inside of the hose isn't distorting (like a brake hose would) thanks to the lower pressure.

Anybody else, any other opinions?
 
Last edited:
Paging any and all mechanics:
So now I'm wondering - did the factory make these clutch lines of the same materials as the brake lines?
If they recognized the reduced stress on the clutch fluid, did they use a cost-cutting lining, or just stick with brake hose line? Anybody know?
My bike is 20 years old and has had one clutch replacement, plus many fluid flushes (love that fitting on the end of the hose), and I've never had an issue with clutch actuation and I've never noticed bitso'crap in the old fluid.
So is this something that all of us Oilhead riders should seriously consider?

May 02 - So far, two guys have said they've never seen a bad clutch hose on an Oilhead (I didn't ask about other bikes or manufacturers), but they have seen seeping fittings and slave cylinder seals; also, if they saw junk in the flush, it was always due to a seal.
One said that the swap "probably" wouldn't change the feel of the clutch, first because hydraulics pretty much hide what's happening down there anyway, and second because the inside of the hose isn't distorting (like a brake hose would) thanks to the lower pressure.

Anybody else, any other opinions?
Thanks so much for that feedback. I really appreciate it. Based on the input you’ve gathered, it doesn’t sound like replacing that clutch line is absolutely necessary and any interior rubber deterioration may not be what’s causing my problem. That’s very reassuring, but it completely blows my theory apart. Made sense to me anyway. I’m assuming the clutch line is made of a different material and not the same as the brake lines.

At this point, I may just go ahead and replace that clutch line anyway since I’m going to be flushing the system with new fluid and chalk it up to preventative maintenance. Besides, I must admit I do like the aesthetics and it would match the braided stainless steel brake lines.
 
Details on the info I've gotten on this:
Over at Long Beach BMW, the parts babe (Chelsea) AND the parts manager (Dewey) each independently said that they do not recall ever selling a new replacement 1150 clutch hose. I even had Chelsea bring it up on the official fiche to help jog her memory before asking her.
I also went over to Valdi's shop (plug alert! https://valdismotozone.com/), and the only time he ever replaced one was when a customer somehow kinked the line during some other action. (Makes good sense: metal tends to break at such points.) He showed me the old line - it is steel-spiral-wrapped, so I doubt the Speigler would be any better (except that it's about $180 cheaper! and custom colors can be nice). He also reiterated that when the clutch fluid gets dark, it's almost always due to the slave cylinder.
 
Wow! Thanks for checking that out for me. I really appreciate it. Long Beach BMW…that brings back memories. That dealership and Irv Seavers BMW . in Orange have been around nearly as long as I can remember. Growing up in OC and living there most of my life, I recall driving out there periodically to look around, see what was new and what bikes had come in on trade.

Good to know that the factory clutch line is steel-spiral wrapped. I had no idea. As far as the slave cylinder goes. I’m not sure what to think. The clutch fluid isn’t dark. In fact, it looks fairly normal, so I’m feeling somewhat perplexed.
 
Wow! Thanks for checking that out for me. I really appreciate it. Long Beach BMW…that brings back memories. That dealership and Irv Seavers BMW . in Orange have been around nearly as long as I can remember. Growing up in OC and living there most of my life, I recall driving out there periodically to look around, see what was new and what bikes had come in on trade.

Good to know that the factory clutch line is steel-spiral wrapped. I had no idea. As far as the slave cylinder goes. I’m not sure what to think. The clutch fluid isn’t dark. In fact, it looks fairly normal, so I’m feeling somewhat perplexed.
Reading your thread.., trying to learn as much as possible. Look what I have! Got my '09 K1300s from them.
 

Attachments

  • 20240507_225941.jpg
    20240507_225941.jpg
    398.7 KB · Views: 4
Details on the info I've gotten on this:
Over at Long Beach BMW, the parts babe (Chelsea) AND the parts manager (Dewey) each independently said that they do not recall ever selling a new replacement 1150 clutch hose. I even had Chelsea bring it up on the official fiche to help jog her memory before asking her.
I also went over to Valdi's shop (plug alert! https://valdismotozone.com/), and the only time he ever replaced one was when a customer somehow kinked the line during some other action. (Makes good sense: metal tends to break at such points.) He showed me the old line - it is steel-spiral-wrapped, so I doubt the Speigler would be any better (except that it's about $180 cheaper! and custom colors can be nice). He also reiterated that when the clutch fluid gets dark, it's almost always due to the slave cylinder.
Details on the info I've gotten on this:
Over at Long Beach BMW, the parts babe (Chelsea) AND the parts manager (Dewey) each independently said that they do not recall ever selling a new replacement 1150 clutch hose. I even had Chelsea bring it up on the official fiche to help jog her memory before asking her.
I also went over to Valdi's shop (plug alert! https://valdismotozone.com/), and the only time he ever replaced one was when a customer somehow kinked the line during some other action. (Makes good sense: metal tends to break at such points.) He showed me the old line - it is steel-spiral-wrapped, so I doubt the Speigler would be any better (except that it's about $180 cheaper! and custom colors can be nice). He also reiterated that when the clutch fluid gets dark, it's almost always due to the slave cylinder.
my experience is the same with the clutch slave cylinder hose, the 1150 originally used brake fluid in the slave cylinder circuit that should be light amber, the mineral based fluid is darker
 
Back
Top