GS Specific Clutch FAQ
compiled & edited by Kristian #562 & NickJC #1085
Please read the Disclaimer before attempting any work in this FAQ.
For General Clutch Issues Refer the
Classic Misc Probs Clutch FAQ
If you are looking for information about Clutch Adjustment see the Clutch Adjustment FAQ
For Replacement Clutch Levers (On Handlebar) refer Aftermarket Levers FAQ
For Gear Change problems
For Cables & Cable Routing
GS Clutch stiffer than the Classic
by Kristian #562
As a Former Classic owner and now a GS owner, I noticed the GS Clutch was (and still is) considerably stiffer than the Classic.
The extra pull on the lever is likely do to the increase in the amount of plates and spacers in this clutch compared to the Classic. The clutch should slip less and last longer.
Looking in the parts CD the parts numbers for the clutch kits were not the same for the GS and Classic. If there are different part numbers for the clutch plates between the GS and Classic, there ~might~ have been considerable changes in some of the basic parts, and you can't depend on the BMW parts numbers to tell you, sometimes the same part can be listed under 2 different part numbers between models.
Plus there's at least 2, possibly 3 variations of replacement plates for the Classic Clutch, depending on serial number. (That's the kind of info covered by a factory TSB or SI.) So far no one knows if any parts of the GS kit would be possible to retrofit into a Classic clutch. The trick would be to go in to a dealer to look at the 2 different kits. One of the hi performance places (Pami or Wood) lists an F650 clutch pack with an extra plate or two.
More plates hopefully reduces slipping and the clutch lasts longer, but it's not necessarily true that a couple more plates necessarily require more hand pressure. That's a factor of too many variables, especially SPRINGS. Then there's external influences which might be different for GS vs. Classic, like lever mechanisms on both ends of the cables, the cables themselves, maybe an entirely redesigned or modified release bearing (rack and pinion). Then there's just weirdness - (greatly worn) identical bikes can have different clutch feel due to wear. Thanks again to HsN.
Update: The reason for was the Clutch Cable. I changed it and WOW! what a difference. If you have an early model GS, check the Cable. See "What is the Story with these Two Different Clutch Cable Part Numbers for the GS Clutch"
Alternative Solutions to Stiff Clutch
Go to www.chaparral-racing.com, type "easy clutch" in the search box and click on the picture. still the same part numbers and price. I'm not advocating this device, only telling you about it. I have no experience with it what-so-ever, I just thought it might be worth a shot. As I stated earlier it is on page 386 of my 2001 cat. I don't have a 2002 issue for some reason but the 2001 part no. is 306-9000 for Japanese, and 306-9001 for European. not sure of the difference. the description says: "this unit uses a leverage ratio to reduce clutch pull on dirt bikes and ATV's up to 44%. easy to use and easy to install. weighs only 3.1 oz. lifetime warranty." the price listed is $36.99. I'm sure you could call and reference the part no. as being in the 2001 cat and they could cross reference it to the 2002 cat if there is a difference. you may could find it on their website. I can't say for sure if it would be a direct installation or not which is why I stated earlier about someone maybe adapting it to work on your bike. but who knows it may just go right on with no mods. in the picture it looks like a pretty simple device. good luck and keep us posted on results. Randy, Newnan, GA
Another possible alternative is a Magura hydraulic clutch, not sure about applications. I also remember seeing somewhere, a kit that increased the mechanical advantage in leverage much like your idea but was all done at the hand lever end. Can't remember the name or company though. Also a new product called revloc. It is rather expensive but I read good reviews. it is a kit that replaces the entire clutch assembly and converts it into a centrifugal clutch. the manual clutch function remains, but is not required for most riding. again not sure about applications but I read they were developing new ones all the time as they are relatively new to the market place. sounded like a neat set-up. I read about it in one of the mainstream moto-mags in the last few months but can't remember which one. making sure you keep the clutch cable and all pivots well lubed helps reduce effort slightly and I usually take 3 or 4 ibuprofen tabs before a ride due to carpal tunnel syndrome. it helps me a lot but I'm sure you have already investigated the medication route. Practice your clutchless upshift technique and shift into neutral at long stops to reduce hand fatigue. Randy, Newnan, GA
For the old BMW Airheads there is a clutch fix called the Easy Clutch. It effectively halves the effort and doubles the length of the "friction zone" of the Airheads by running the stock cable over a pulley wheel and anchoring the far end to a fixed mounting (this version looks to have a "bolt on" chain attachment for the cable, mine uses the cable "as is"). The pulley wheel mounting is then attached to the original clutch lever. This gives you a mechanical advantage. Not sure if it can be applied to the F650 setup, but it might get you thinking in the right direction. http://members.aol.com/vechbmw2/clutch.html. Marty #436-Chicago-97 F650F.
F650GS/Dakar Clutch Cover Removal
North Queensland, Oz
This modification appears to be necessary for removal of the clutch cover on F650GS and Dakar models.
Incidentally, The Manual Says:
-Remove Exhaust Manifold
-Remove Left Footrest (Peg)
-Disconnect Oil Return Line from the Engine and the Oil Tank
So I guess those two above are what BMW say you need to remove to get the Oil Line Out. Not that I'd want to do that every time mind you. I like your tube better, though I'd take it off once BMW's way first to cut the darn thing.
After removing all the bolts for the left cover, slide the left cover outward about 3/8 inch. This will create a gap large enough for the oil pipe to drop into. Now the oil pipe can be rotated and removed. With the pipe removed, the left cover can be removed.
Changing the clutch cutout switch
NOTE: If anyone can supply pictures to
supplement each of these steps please contact the
by Robin #790, '01 GSD Chicago
As it seems to be the week for all of my switches to go bad on my '01 Dakar (approx. 36K miles), my clutch cut-out switch decided to fail. This is the switch that allows you to start the bike in gear with the clutch pulled in. Needless to say, it's inconvenient to have to look for neutral before you can restart. Installation of the switch is simple, but you have to remove a fair amount of stuff.
1) All the faux tank panels.
1) Oil tank
2) Coolant catch tank
3) Cover from electrical panel (Photo showing switch location)
After that's all off, it's a pretty simple matter to:
A) Slice the wire ties holding all the wires together
B) Rremove the faulty switch and wire
C) Replace with the new one.
NOTE: The only tricky part is screwing the switch back into the clutch lever housing. As the threaded part does not move independent of the wire, just threading it in
would result in a twisted wire. Pre-twisting the wire in the opposite direction takes care of the problem.
D) Button everything up in the reverse order, and you're ready to go.
NOTE: I prefer to leave the battery in place until I get the oil tank and airbox off.
It makes it easier (marginally) to access the terminals for disconnection and connection.
slippage - Loner
My '01 650 GS has 20k on it and I just had the oil changed at the dealership. Now my clutch is slipping in 4th and 5th gears. I've had synthetic in there since about 10k and they put synthetic in so I'm not sure if that is the problem. I've looked at everything on the site and it looks as though my best bet is to change the oil again first. The clutch adjustment distances are good. It seems to happen most after the bike is warm, and I first noticed it on the way home from the dealership.
A's and Opinions.
I have had clutch slippage on and off for "several" years now. I have tried to "cure" it with different oils and so on, but it is still slipping if "provoked". Others have tried to use stronger clutch springs, and it seems the clutch release mechanism does not cope with the hard springs. haakon#626 (Norway, F650GS)
The clutch on my Classic slipped almost from new if I was a too enthusiastic with the throttle. I went to 15 tooth countershaft sprocket and it cured the problem. The change in gearing made RPMs higher through the range, but that wasn't as much an issue as the slippage and I was able to cruise at 80 easily. Harl #380
The clutch is probably fine. The springs compress and allow the clutch to slip. I changed my clutch and springs. The springs are very cheap and not hard to change. Do not use aftermarket springs. Steve#417(in,us)
I would start thinking about damage to the clutch throw-out lever. Check the FAQs. Kristian had a real problem when this device ground up its worm gear and stopped pushing on the clutch. Richard #230
Kristian ran into this problem after installing after market stiff springs. Steve#417(in,us)
When I worked at a dealership that sold Norton's almost everyone of them had clutch slippage problems, the cure was to surface plate the steel plates to make them perfectly flat. We would glue a piece of emery clothe to a piece of glass and move the clutch disk around in a figure 8 motion until you could no longer see high spots (do both sides). This made the clutches work better in every way-no dragging and no slipping. It's cheap and easy and would have the advantage of removing the friction modifiers from the synthetic oil if you did the friction plates also. You can use a flywheel from an old Japanese enduro bike with the strong magnets to hold the plates while you are rubbing them on the surface plate(this will keep you from sanding the tips of your fingers off) although can do it by hand. Also be sure you clean and degrease the plates first or the emery paper will gum op right away. - mcguiver
NOTE: << You can use a flywheel from an old japanese enduro bike with the
strong magnets to hold the plates >> I personally would not do this.....I would be worried that the clutch
plates could end up "slightly" magnetic, and attract metal stuff to them, sort
of like the magnetic drain plug. Jack, F650GS, Rockhampton, Qld, Australia.
Work Actually done and data found
by Marty #436- Chicago-97 F650F
My clutch started slipping intermittently under high load when I went to a 17-tooth sprocket. It kept asking for more "free play" in the clutch cable (using up what was already there). Before the BMWMOA National, I moved the actuator lever on the clutch housing two teeth...and used up all that free play in the mountains at the National. Haven't pulled it apart (yet), but I'm expecting that the springs have "sprung" due to heat or age. Bad news is that I had to do my 1000 mile day and 4K (Mt. Evans) on my K75RT instead... :-(
Hopefully I will rip into this project tonight (so I might be able to get the clutch repair kit from one of the two "local" BMW dealers tomorrow, if needed). If not, definitely get into it for sure this weekend. I have in my possession 6 clutch springs for a 1980 Honda XL500 ($25 worth-see previous thread/translation from German website), and am hoping/expecting that that will be the problem. I WILL take a very close look at the rack and pinion actuator gears, and measure/ examine the clutch pack disks (and put REAL bolts back in). I did not see in the FAQ any information on service limits/dimensions for the clutch pack/disks/stack or the spring height (anybody have the BMW manual with those numbers?) I did find one reference to the Clymer numbers being wrong (I don't have one of those, either) and want to confirm. I also noted a lack of pics in this FAQ and will try to snap some as I go...(I see a revised FAQ in my future). I'll also report on those Honda springs vs. BMW (used). (BTW, the Honda only uses 4 clutch springs). I figure if I need the rack or pinion actuator, I'm done for a few days anyway. Bob's BMW catalog lists a washer (IIRC) that must be replaced when working on the clutch...is this the crush washer for the coolant drain bolt, or is there some type of locking tab gizmo like on the front sprocket (and can it be re-used?). To Flash...I'll try to continue on with the oil test (i.e. not drain anymore oil than I have to...)
OK, pulled the clutch tonight. Rack and pinion look OK. Clutch pack measures 33.5mm. According to one comment in the FAQ, that would be 1.5mm under the service limit, can anyone with the service manual confirm? Also, the springs currently measure 43.2mm. One source (thread) indicates original length is 44mm, can anyone confirm this, or provide the minimum service length? Looks like I'll check whether either Chicago BMW dealer stocks the clutch kit tomorrow.
Chicago BMW = no stock. Tag BMW had 2 in stock. I ended up with an open bag (that came from Laurel BMW, that closed a couple of years ago, so OLD stock). Clutch plates looked to be a match, so I dumped them in a pan of oil to start soaking prior to assembly. (Had to run my wife off to the airport). I had recently purchased some springs for a 1980 Honda XL500 (since when do Jap dealers stock parts this long??? Hmmm...), due to a comment from a previous thread. Good thing I did, because when I measured the old springs, they were roughly 1.7"/43.3 mm long. The NEW BMW springs in the clutch kit are 1.2"/30.4 mm. The spring wire thickness of the old are .102" vs. 0.166" for the new. OD of the old is 0.80" vs. 0.69" for the new. ID of the old is .59" vs. .35" for the new. 8 coils for the old vs. 6 coils on the new. The correct part number is on the bag, but needless to say, the correct parts are not IN the bag. It will be 3 weeks before I can get back to TAG BMW...teaching MSF class next weekend, rally the following weekend. As a result, I will be installing the Honda springs, as their specs are compared as follows...length 1.705" (used BMW) vs 1.731" (H); spring wire 0.102" (BMW) vs. 0.106" (H); OD 0.796" (BMW) vs. 0.804" (H); ID 0.586" (BMW) vs. 0.587" (H); coils 8 (BMW) vs. 8.25 (H). BTW, I tried to measure the spring rate by putting an old slide hammer weight on top of the spring and measuring the compression. Too little deflection to get a significant result. Assuming that they are made from the same metal/hardness/temper (a BIG assumption), the length is likely closer to what NEW BMW springs should be, the ID, OD, and # of coils are very close to OEM, and the slightly thicker spring wire should give SLIGHTLY more clutch pressure. I'm off to try and put this stuff together (and will check metal plates for flatness). To Nick...I'll send you a copy of the present spreadsheet with all my measurements. But I'll hold off until/if I get the new BMW springs to measure as well.
The Honda springs fit and work (at least for the first 50 miles or so). The BMW dealer mailed me the correct spring set (better service than I expected), which I will measure and add to the information I will put together for the FAQ. FWIW, the new springs feel SLIGHTLY stiffer than the old ones (the old ones may have been weakened?). The rack and gear actuator had no visible wear.