FMF C.E.B. clutch
Posted July 31, 2004 - 04:36 PM
Posted July 31, 2004 - 05:10 PM
**Found it under the info section**
$999?!! HOLY $#@%!!!
Posted August 01, 2004 - 02:25 PM
fmf c.e.b. - slipper clutch, slips to eliminate engine braking. works like a stock clutch from a dead stop.
z start - auto clutch, slips at low rpm for automatic clutch engagement. the lever is optional.
ive heard the z start can work like a slipper clutch, but i dont understand how.
Posted August 01, 2004 - 04:17 PM
Posted August 06, 2004 - 08:17 AM
Posted August 06, 2004 - 02:10 PM
did they say it also eliminates engine braking?
its been my experience that automatic clutch engagement, when used for out-of-the-corner MX type situations, is imprecise and slushy since the "set rpm" has to be very high. it soaks up the snap, exludes you from lugging the engine and causes major heat build up.
a grand? complete rekluse clutch - 500 bones.
Posted August 06, 2004 - 05:19 PM
Posted August 07, 2004 - 03:51 AM
Posted August 07, 2004 - 11:13 PM
ya not real sure what the rpm range is but he definatly said it was adjustable i mentioned on a hill climb if you set your idle much higher(say 2000rpm) than your stall speed(which is say 1000 rpm?) and then set the clutch to between idle and just above stall(say around 1500 rpm) if it would eliminate the stall but yet still act as a normal clutch if pulled revved and dumped and he agreed that it would
thats a complicated question. first, for a z start, the stall speed would have to be at around 3000 rpm to get full engagement by 4500 rpm. if the stall speed is very low the bike will creep when stopped in gear, or you may kill the engine with braking. a high idle would make the dragging worse.
also with a z start, you set the stall speed and pick an engagement rate (light or heavy spring), then your done. there no "setting the clutch" after you set the stall speed. that may be different with the evoluzione.
basically the evoluzione and z start sound the same to me, except the evoluzione wants to eliminate some engine braking by using a whole new clutch design.
these clutches make it seem like you can do the impossible (as far as setup goes), but they are limited to certain factors - since they are centrifigal. i have loved it, hated it, now i love it again... all because of setup.
if you really hate engine braking, then the evoluzione would be the way to go. otherwise i would seriously consider a rekluse.
Posted August 08, 2004 - 01:55 PM
Posted August 08, 2004 - 09:34 PM
there is also no clutch pull anymore, as in one finger is more than you'll ever need to pull in the lever. i only use the lever when taking off or brake sliding, and to find nuetral. this clutch is a luxury item, i will never have a bike without a z start.
Posted August 09, 2004 - 05:55 AM
Posted August 09, 2004 - 07:36 AM
WRT the z-Start setup as an anti-stall device/minimal clutch slip. This can be done. Running 5 Tungsten Carbide balls (25 steel/5 TC balls) in a YZ/WR 450 with the light external adjuster spring will give a very abrupt engagement, almost no slip at all. I ran this setup a couple of weeks ago on my YZ450 and it worked pretty well with the tall stock gearing of the YZ450 on tight trails.
Personally I prefer just dropping to a 13T countershaft and running all steel balls in the YZ450 for the tight trails. A little bit of slip actually works good, especially in the rocks.
Tungsten Carbide balls are available from us, they're $5 each.
I wish I could comment some on the differences between the STM and the z-Start but I have not been able to ride with the STM and would likely only spread disinformation. You might want to check the Supermoto forum for more info.
Posted August 11, 2004 - 07:55 PM
WRT the z-Start setup as an anti-stall device/minimal clutch slip. This can be done. Running 5 Tungsten Carbide balls (25 steel/5 TC balls) in a YZ/WR 450 with the light external adjuster spring will give a very abrupt engagement, almost no slip at all.
i knew al would chime in. nc, this is the setup that im using. im running 5 tungsten carbide balls... it does lower the stall speed enough for me. basically you dont want to have to use the lever to stop, or you'll stall the engine during sudden braking. you want the engagement just above idle, but not so low that the auto part is uneffective.
i get serious chatter with mine, but al has told me this is a pre-04 problem. my off road gearing (15/47) also makes the chatter alot worse, but thats with my YZ tranny. the clutch actually compensates very well for my setup, but im always trying to eliminate as much slip as possible while allowing the auto-engagement to work without too much drag. my bike doesnt creep, but does drag a bit. with the lever, its never a problem.
Posted August 12, 2004 - 04:57 PM
Posted August 12, 2004 - 05:55 PM
now with these heavier balls, i was under the impression you could only use multiples of 30, as in 3,5,6, or 10 balls. since the clutch has 30 balls its important to balance the wieght. i cant figure why al told you that you could use 8 balls.
it seems to me that the heavier spring counteracts the carbide balls. the more carbide balls you use, the lower the stall speed. the more spring tension you use, the higher the stall speed. you want 5 or more carbide balls and very little tension on the light spring. the heavy spring is useless to me (and you).
if your stall speed is at idle, you will kill the engine. to keep from stalling, the clutch has to release before it drops to idle. my setup works flawlessly
Posted August 13, 2004 - 04:22 AM
Posted August 13, 2004 - 04:28 AM
TC balls "steepen" the engagement curve. It takes more spring force (pre-load) to get the same stall speed but then the clutch creates more force at low engine speeds with the TC balls. The transition from not engaged to slip to fully locked up becomes very short with more TC balls.
Some bikes can take more TC balls than others. The YZF has a reasonably tall primary ratio (clutch spins faster, more centrifugal force for any given engine speed) and lots of clutch surface area (more friction). A few TC balls can make a big difference. A Husaberg or a Husky needs 15 TC balls stock to get the same kind of hookup a Yamaha gets with all steel. This is due to a slower primary ratio and also due to a fairly high rate return spring in the clutch slave cylinder. High rate springs are also kind of a bad thing for a centrifugal clutch to overcome (lots of additional force builds against the clutch as it moves from .035" off the clutch pack into the clutch pack).
Hope this info helps...