clutch slipping at full power - Harley Forum

03fxst · #1 07-11-2009, 06:34 PM

Hmmm

Not sure if the clutch is worn or if I have pushed the torque too high. I adjusted it as per the manual as I have done in the past. In second gear at full throttle she pulls like crazy and then for a second or so as it approaches top rpm the clutch lets go and then grabs hold again. The revs go up but the speedometer sits right where it was. Then I either shift up or it grabs and then I shift. Should I go for a heavier spring set-up ie the Barnett clutch spring replacement kit or do I need to repack the whole basket with new discs and plates? If the latter do I buy oem or go for something beefier.

two steps forward and one new problem....

03FXST

unclepsycho · #2 07-11-2009, 07:00 PM

I was lucky my bike was under warentee when it did that.... I ended up beating it till it let go completely. Then I upgraded to a Kevlar clutch. the first pressure plate did exactly what you describe, and I had the shop look at it again. turns out the pressure plate was ''warped'' or not seating flat, so they replaced it and had no trouble after that....except for the final drive belt jumping and rattling the tranny like carzy.

My bike is an '04 BMC with a 100" revtech(evo) and a 6-speed Baker.

Start by taking off the primary cover, and pull in the clutch , Motor NOT running. make sure it comes out and goes back in perfectly with no lateral twisting. if all looks good, then maybe it is just starting to wear out. then you may as well upgrade to heavier springs and the good clutch plates.

03fxst · #3 07-13-2009, 11:30 PM

Thanks Unc
Looks fine when I pull and release. I'll look at putting in new discs and plates. No slippage other than full throttle pulls at the top of the gear so I'll stop doing that until I put in the new plates.

I suppose I could have left it stock....but where's the fun in that.
03FXST

03fxst · #4 07-15-2009, 09:53 AM

Just picked up a Rekluse Torq drive. Found it browsing the J&P catalogue but thought it was claiming too much. Easier pull at the handle bar and more grab at the clutch. Stopped into a performance shop to ask about it and the mechanic had the tech sheet for it stuck to his tool box. He pulled one apart to show me the ball and ramp set up between the pressure plates.
One of the plates is slotted so it slides on the clutch stand-offs and pushes the other out against a spring set up with the ballbearings in the grooved ramps increasing the pressure on the clutch itself. He had one on the shelf so I bought it. Will install it today. Anyone ever tried it or is my Hog the guinea pig.

Sometimes you gotta just try something new.
03FXST

03fxst · #5 07-15-2009, 08:26 PM

Fairly easy install. My clutch pac measured within the specs as outlined in the directions. Outside of spec would have meant replacing it, Took a test run. No more slipping at high rpm. Can run it right up to the rev limiter and it just keeps pulling. Clutch lever feels like it isn't pulling anything at all. It is very light. At first I thought it wasn't going to work but when I slipped from neutral down to first there was no creeping. It grabs later than it used to though. Handle is about halfway out from the bar before I feel any pull. It used to be right off the bar. I suppose I can get used to that.

so far so good..
03FXST

evoKENevo · #6 07-15-2009, 09:08 PM

Yo,O3
When you implied that your bike used to "creep" when you shifted from neutral to first, the first thing I thunk was that your clutch and cable were'nt adjusted right and your clutch plates were'n fully disengaging. And then when you said it used to grab when your lever was right off the bar I knew your clutch and cable were'nt adjusted right. When it is right (as it seems to be now) it should start to disengage when the lever is almost all the way out...and start to engage where it does now.

That does'nt explain why your clutch was slipping at higher RPMs and I'd like to learn more about how/why this new gadget seems to have cured that problem...but it definitely explains why you're not "creeping" with your clutch lever pulled in all the way anymore. Meanwhile, get used to the way it works now

it's a good thing. In fact it may be part of why clutching seems easier now...and I bet you'll learn to like not having to pull your clutch lever in so far while shifting gears, too...better for those "power

shifts"

03fxst · #7 07-16-2009, 09:55 PM

Thanks Ken
In heavy traffic today the much easier shorter lever pull was a treat. No more squeezing the bar. It didn't quite creep before, just flexed the suspension when cold and then settled in. The simple explanation on the torq drive is its three plate two spring design. The bottom plate has the threaded opening in the centre for the clutch thow out post and lock-nut. That plate presses into the friction plates sits over the clutch stand-offs but has open slots at each post so it can turn say from twelve to one o'clock. The ball bearings sit in ramped grooves on the outer edge of that plate. the second plate, also has ramped grooves to sandwich the ball bearings. It has holes for the stand-offs not slots so it does not twist with the first but stays firmly positioned on those stand-off posts where it can rise and fall. The ball bearings push it out as the first plate twists in those slots while maintaining contact with the pressure plate. Two springs sit outside that second plate. They are pressed into place by a third plate that torques everything into those stand-offs. So as the first plate twists it pushes the second but rather than moving out the second plate resists because of the heavier spring so the ball-bearings and ramps are actually forcing the first plate back into the clutch pac with more strength.
The lighter spring is responsible for the easier clutch pull at low torque.

Hoping it lasts.
03FXST

evoKENevo · #8 07-16-2009, 10:22 PM

"Ha"...believe OR not...I actually understand

what you wrote...and it all seems to make good sense...good writing/explaination helped more than the pictures etc on their website...thanks