F650 Stiffer Clutch Springs
by Kristian #562, 15/10/01
Please read the Disclaimer before
attempting any work in this FAQ.
Last Updated: 18 Feb 2007, by Winter #1935
- General Questions
- Why would I want to put in stiffer clutch springs?
- Where can I get them?
- Is there a cheaper alternative?
- Are there any Drawbacks?
- Are the new springs worth it?
- OK I bought a set anyway. How do I install them?
- Is there any other work I can do when/if I install them?
- Clutch Actuator Breakage!
For other related FAQs:
- Two reasons, one is to prevent
clutch slip if
you've beefed up your power by re-jetting or som other means, the second
is to prolong the power at high revs, which is where
clutch plate slip
is first noticeable. You may notice using some oils cause more slip than
others. The Oil I use states made for Bikes with wet clutches to
reduce slip. See the Oil FAQ.
- Note ""One of the most probable reasons for a slipping
clutch (assuming everything is adjusted OK) is the use of EC (Energy
Conserving) rated oils. (Has an EC in the API - American Petroleum
Institute) star logo. Not sure if you have them in HK or Europe, or how
they are marked (probably NOT with an API symbol!) but they are very
common in the US, especially with the synthetic oils. The EC additives are
VERY BAD for use with wet clutches, cause excessive slippage, and are
difficult to "wash" out if used - might take several oil
changes. In other BMW's with a dry clutch, using EC oils is common, so
it's probably a common mistake in the service shop also."
Where can I get them?
- Well, one source is Team-Pami
in Germany, where I got mine. I have no affiliation with Team-Pami. Ron
Woods has probably also got a set.
Is there a cheaper alternative?
- Flash had a great Idea. Shim the existing ones.! i.e. Don't buy
new springs, just put a washer in the
Plate Holder Wells or behind the existing one on each of the 6 the
Bolts and presto, stiffer clutch.
Are there any Drawbacks?
- Well there definitely could be a couple. The first is I am
on my SECOND Clutch fork, it's soft aluminium an
could be because I tightened it up too tight or I took it on/off too
often, but I know I'm on my third since the spring replacement
- The second is that the clutch lever is harder to pull in, so if
you have small hands or weak hands don't consider it, particularly if you
drive a lot in traffic, where you need to control the bike with the
clutch. These bikes are not too good at low revs, so you really need that
clutch control at low speed in traffic.
- The third is it puts a lot of strain on your
Clutch Release Bearing and
Actuator Arm Spline (First Set) and could cause it to wear then FAIL,
eventually causing the clutch to "Jam". Here's my
Release Bearing and Actuator Arm Spline (Second Set). Admittedly I
DID get a used one when I replaced it the first time and it MAY have come
off a 1995 or 1995 bike. I just do not know which model year it came off.
But I'm not the only one to whom this failure has occurred. Refer the
Clutch Misc. Problems FAQ for
Here's what Team Pami said about it:
> From: Gottfried Michels INFO@TEAM-PAMI.DE
> Sent: Friday, October 12, 2001 2:29:40 PM
You are the second person which (sic) has problems with the clutch gears.
Please note that the "spring preload" is only 12-16% higher -
and that should destroy the parts? I can't believe that the stock parts
that "close on the limit" ??
Model year 1994 and 95 had problems with these parts as they were to
"soft" - not hardened enough. I knew that BMW changed the
parts/production process in year 96. From that time we heard nothing from
that parts (for the Paris Dakar engines we take stock parts out of year
Gottfried - Team Pami
Are the new springs worth it?
- For the average rider? Nope, they might hold power slightly longer
on a heavily loaded uphill, but IMHO the stock ones are fine. Use Good Oil
- Ramey from Ron Woods racing has previously observed that with e.g.
Redline FULLY Synthetic Oil people with Clutch Problems went away
OK I bought a set anyway. How do I install them?
Is there any other work I can do when/if I install them?
- Sure there is. You can replace your water pump shaft and seals
Water pump Repair FAQ and I
would recommend replacing the gear shifter and clutch shifter-shaft seals.
Also, have a good look at your shifter-shaft splines and you clutch
release bearing. See Clutch
Cover Removal Problems.
- The Part # of the longer 6" vertical shaft, that rotates,
with the cable end lever spline on one end sticking out of the engine
cover, and the gear (rack) teeth on the other end, is 21 21 2 343 177.
- The Part# of the fat 3" Horizontal Rack (release bearing),
pulled by the above (177) part, inside the engine at the end of the clutch
basket, that actually pulls/loosens the clutch late pack, is
21 21 2 343 175.
Thanks to Hombre sin Nombre
Clutch Actuator Breakage!
- I am having problems with a classic F650 breaking the clutch actuator teeth when using stiff clutch springs. I was wondering if the new FI GS has upgraded these parts with stronger ones or a better design? If so, would the parts work in the classic? Has anyone fabricated there own stronger clutch actuator parts? Is there any "treatment" that will make the metal stronger? ScoobyDFW
- To make the problem go away, don't use stiffer clutch springs. Q.E.D. Flash 412 (CO)
- I bought the stiffer springs at
On my F650 the clutch started to slip at about 10.000 miles. On my F650GS
which is noticeable stronger than the old model the clutch started to slip
at about 3.000 miles. Robert
- Some random thoughts on clutch mechanics. New clutch plates are
thicker than old ones. This means the the same old springs will work
better with new plates than with worn plates. You can shim the old springs
with washers to give them added strength. So, if your clutch is slipping
and the plates are not at the wear limit, you might try adding some
washers to the springs before replacing pieces. If your plates are worn,
you might try adding some washers while you're in there, just for grins.
You can always take them back out. Flash #412
- Clutch Parts: Hi, the part number for 1 disc (you need 7 discs) is
: 21 21 2 343 170. Or you buy a complete clutch replacement kit (with 7
discs and springs). Part-nr. : 21 21 2 343 464. Don't forget to buy a seal
for the left cover, in most cases it gets damaged while disassembling.
Part-nr. : 11 14 2 343 039 And before disassembling the clutch (just 4 or
5 screws with springs behind them) take a look at the discs in order to
see the sequence and the surface the discs are inserted. (You can insert
them "the wrong way", so take a close look). Oliver (BMW