I have been lurking on this forum for years, but contributed very little so thought it is my turn now… My ’02 bike has 92 000 km (57 000 miles) on the meter and I started to get worried about the condition of the clutch splines. During the late autumn and Christmas time I “cut the bike in half”.
While disassembling the bike I followed the BMW repair manual and information found on this and some other web forums. I took the gearbox and driveshaft out as one whole unit since I had replaced the FD pivot bearings just last winter so did not see any reason to take things apart again.
BMW manual does not mention anything about removing the throttle bodies but I was afraid of damaging the cables or something else while lifting the rear frame so I took them out. I replaced the large O-rings between the throttle bodies and inlet tubes. Actually it was the second time this autumn/winter that I removed the LHS throttle body. The first time was when I changed the camchain tensioner to the newer version.
For some reason BMW manual requests to disconnect the plug of the side-stand switch but I did not see why this should be necessary. Additionally, I think that disconnecting the gear indicator plug could be done after lifting the rear frame and this would probably make it easier to pull/push/wiggle the plug out between the frame rail, battery box and wire loom. It took a while to get it out but I managed to do it anyway. I think some people have simply cut the cable and then soldered it during the re-assembly.
My starter has been working perfectly but it was very dirty so I disassembled, cleaned and lubed the Bendix mechanism using the guide here: http://advwisdom.hogranch.com/Wisdom/ I did not have a 3-leg puller in my toolbox so this was a good excuse to buy one.
My first real “finding” during this work was a badly corroded clutch slave banjo:
This was not that big surprise as I had read about the problem in some forum earlier. I replaced the original clutch line with a steel braided Venhill Powerhose Plus line. Unfortunately the 6mm banjo for the clutch slave cylinder is not available in stainless steel, but since there is not any more the water-collecting outer cover tube I expect that the chromed steel banjo will not give me any problems. (Sorry, no pics of the new parts.) I have used Powerhose Plus lines also for the front brakes and like the look and the quality of the stainless steel fittings.
When I took the slave cylinder out, there was a small amount of some fluid in the housing:
Looks like I was there right at the correct time. After a while the fluid would have started to creep towards the clutch plate along the clutch pushrod. I have been reading about leaking slave cylinders, but I am pretty sure the fluid was gearbox oil. The smell was typical gearbox oil “aroma” and also the color was similar. The slave cylinder itself seemed to be ok and I did not find anything wrong when I opened it, and I did not notice any cloudiness in the clutch fluid.
Anyway, I replaced the slave cylinder with a new one as preventive maintenance since I have seen several failed slave cylinders on different forums and I don’t want that happen to me in the middle of nowhere. Looking at the tiny bearing on the slave piston makes you wonder how it can endure spinning at engine speed for tens of thousands of kilometers, and the only lubrication is the small dab of grease it received during the assembly in the factory. I am not sure if this really is good engineering, but then I am not a mechanical designer. I also drilled a hole in 6 o’clock position like shown here so any future leaks can be seen from outside and the oil or clutch fluid will not sneak to the clutch plate via the clutch pushrod: http://www.r1150r.net/board/viewtopic.php?f=2&t=17736
Talking of the clutch pushrod, I wanted to remove it before taking the gearbox out in order to avoid bending it. This was an interesting experience since first I grabbed the end of the pushrod with pliers and pulled. Nothing happened. Then I used more force and nothing happened. Even more force and still the pushrod did not want to come out (even if the whole bike started to move…). I was already getting desperate but then a strange thing happened: I held the end of the pushrod between my two fingers and, almost by accident, very gently pulled, and, voila, out came the pushrod!
When I pulled the gearbox and driveshaft apart from the engine, this is what I saw:
It looked quite promising but I could not really be sure before I had cleaned the parts:
What a relief to see these parts in almost perfect condition. Before putting the gearbox back in, I changed the input shaft front and rear seals. Based on the color of the new seals (brown instead of black) it seems that BMW has updated them from normal nitrile rubber (NBR) to Viton (FPM) seals that should be more durable. I removed the rear seal by drilling two small holes into it, inserting sheet metal screws in them and pulling the seal out with a slide hammer. However, I found out that this does not work for the front seal as the metal part in it is not wide enough for drilling the holes. So I just pried it out with a screwdriver. I lubed the clutch splines with Honda Moly 60 that I had found in Ebay and then I was ready for re-assembling the bike.
On the re-assembly I had big problems getting the bottom end of the rear shock to the correct position so I could put the bolt in. Finally I realized that the lower part of the shock had rotated slightly, and the sharp edge of the shock bushing somehow cut into the soft aluminium of the swingarm and got stuck there. Afterwards I felt really stupid not noticing this immediately
. When I had rotated the lower part of the shock to the correct position, it slid easily in its place.Another tricky part was installing the fuel distributor since my bike has ABS brakes. I had not taken picture of right side of the bike so that I could see how the fuel lines and brake lines crossed each other. Fortunately I found a picture in this thread http://r1150r.org/board/viewtopic.php?f=2&t=30306 which shows that the fuel lines go between the two metal brake lines. Lesson learnt: take LOTS of pictures during the disassembly.
Otherwise the re-assembly was, as they say, reverse of the disassembly. I have not been able to test the results of my work since we are in the middle of winter in this part of the world, but I do not expect to find any surprises when the riding season starts (only 3 or 4 months waiting…)
I had some mixed feelings when starting the work as I was not sure how difficult it would be. I can do the normal maintenance work and things like changing brake lines etc. In the past I have also changed a stator of a Honda CX500 which is an engine-out job but I have never done a full engine or gearbox rebuild. Spline lube was the first major job that I have done do for my R. Eventually I found out that it was quite easy, it is just the amount of effort that makes it a little hard but I think anyone with normal wrenching skills can do it.
Big thanks go to CycleRob for this very helpful write-up: viewtopic.php?f=2&t=15682&start=0
And as a “thank you” to this forum and all the writers who have provided invaluable information I have (finally) paid my lifetime membership.
-JayTee
). Bike sounds much nicer without being overwhelming. Everything is visible, and I think I should be able to remove the transmission under an hour next time.
