Clutch won't disengage transmission

Doc Stephenson

Doc Stephenson

Member
losing the clutch while riding, so stop and adjusted the cable. after setting the clutch it immediately collapsed when i tried pulling the clutch lever. so this needs investigation. towed it home and started looking inside. found the throw-out bearing had backed itself out a couple of turns. ohhh, I tightened that back to ~150lbft. The clutch pack was oem and warn. i ordered a heavy duty clutch pack, diaphragm, gasket kit, etc. put everything back together, adjusted everything, etc but the clutch didn't seem to disengage when i applied the clutch lever. ok, so i looked at the clutch side. took all that apart but the ramps/ball assembly looked good, so back together. it must be the new pack was sticking. so i took the left side apart again. i compressed the clutch and could see the pushrod moving the pressure plate, i.e. everything is working (mechanically correct anyway), i.e. i must be right the clutch pack itself is stuck to itself or the inner hub. so i unscrew the 4 bolts, pulled the pressure plate, and the clutch pack comes out but it's beautifully greasy and smooth just like when i took it from soaking to assembly. since i was there and just drained all that brand new primary fluid, i let them soak a few more hours before putting everything back together. obviously, adjusted pushrod and clutch cable again. i can still see the pushrod disengage the pressure plate from the assembly but holding it disengaged still does NOT release the transmission. I can't think of anything i'm missing that would explain this behavior. any help would be greatly appreciated....

fyi i've already adjusted the pushrod to every depth between 0 and a full turn back, adjusted the cable play from zero to 1/4 inch, all to no avail. pushrod still appears to disengage the clutch pack (you know that i can only see the pressure plate move away while the pressure plate compresses) without releasing the transmission. i've even tried holding the clutch while someone pushed the bike through compression strokes hoping that would free whatever i couldn't see. nothing seems damaged. i can't hear anything. i'm just at a loss to explain...
 
Jersey Big Mike

Jersey Big Mike

100K mile club
ok, the clutch hub NUT backed out, not the throw out bearing.
I point this out because when I had that happen once and I adjusted clutch on the road, I mangled the throw out bearing.

Check your steel plates and make sure none of them are warped.
Does the transmission go into neutral ok? Spin freely?
Did you check the carrier when it was open that it didn't crack -- they have a habit of doing that when the hub nut loosens up.
Are you sure the plates were put back in correct sequence?

What year/model bike. Who's Heavy Duty clutch pack did you use?
 
W

woodbutcher

Mr. Old Fart member #145
Staff member
what year is the bike? did not see that you had replaced the carrier, some, if not most of the pre-'08's had a poorly designed carrier which would crack. all would look normal until you took it all apart and the center would be completely loose from the rest of the carrier. good luck.
 
Doc Stephenson

Doc Stephenson

Member
sounds like a good plan. i'll take it all apart this weekend and see if the carrier or anything else in the assembly has a problem
thx
 
S

Sven

Well-Known Member
Steel plates have memory. By that I mean, take your hands and touch finger to finger as if praying to a deity. See the tension if you press your fingers against each other? Steels are stamped out and one side is sharp, the other side is smooth at their edges. Now take one hand, lay it over the other fingers. Press both fingers and watch how if the steels were all stacked one way, they would not have resistance when static occurs, meaning, no tension, right? Does the one way direction make sense for assembly? Did you just throw the friction and steels in any old direction?

So you first shuffle the steel plates like a deck of cars so each cut side faces one way. This cut side faces the pressure plate. And as these are now stacked as pancakes on top of each other, hold the stack in your palm and see if each steel sits flat on the next one. Air gap says one is warped and you remove that one, then shuffle, stack the pack again and find zero air gap as you turn the pack looking for another warped steel.

This stacking and direction goes the same for the frictions looking for the obvious warp and assemble facing the pp. Look for a sharp edge or markings on the frictions. Stack the markings [if found] and line those up in the one way pattern as well. For argument sake, drag racers install the cut side of the steels away from the pressure plate. They say they have no problem either way. However, frictions can be installed in their stack direction between steels and pressure plate either way, except if you have a cut sided friction or is marked 'outside,' it usually faces the pressure plate, ala, harley . I suggest all cut sides and makings face the pressure plate.

That's your basic stacking of steels and frictions into the basket. Basket outer is chained/belted to the crank so this always spins. For argument sake, say a friction is the first plate that touches the clutch outer. As the outer spins with the crank, this friction is first on the collapse so as to touch the spinning engine first. Frictions lock to basket outer. Clutch inner call it, the steels are locked to this. The output shaft is locked to the clutch inner and is chained/belted to the rear wheel. The pushrod separates both plates just so far. With a warp steel it can drag the frictions enough to keep the bike rolling, grind 1st gear's teeth off while the friction should be away from the ever spinning clutch outer. This is your narrow down point as to creep/gear grind. Make senses so far?

Think about the ramp, rod gap, springs, and final throw at the pressure plate:
1. Ramp; is going to rise from sitting in those deep pockets, what, about 3/8" maybe? Rod is going to push the ramp home on the adjust screw, right?
2. Rod; will need the expansion gap and who cares if it zero or an 1/8th turn out, the ramp is going to still push the pressure plate off the stack.
3. Gap; Zero clearance means the rod grows and pushes the pressure plate out so the plates slip... your bike, your adjustment.
4. Springs; When the plates wear, the springs grow, the tension is not as strong, you slip. You still catch N, you still clunk into 1st, no creep, just as flat as new, but out of spec to stack to tension.
5. Pressure plate; is designed a few ways. One is with springs, or the other is the spring and pressure plate, called a wave plate. Wave plate in the static is cone shaped. When the stack is within spec, those combined steels and frictions push the wave plate flat and there is your spring tension and break-free of the plates. When this wave plate goes back to memory, the plates do have the full ramp rise, but the spring is too coned to give the plates a gap to break-free. Your lever loses cable gap because the adjust screw moved with the cone moving into the clutch outer. You no longer can move the wave plate flat so are back to hard finding N, gear grind, etc.

Lastly is how deep are the indents of the friction tangs on the clutch outer forks tabs? How deep are the clutch center grooves in that part, and if deep, they stay locked in those grooves and now just one steel needs to cause a friction to keep moving shaft, where grind goes the gear, and a dr. appointment for an ankle sprain looking for N.

Got enough clues if I explained the theory behind the moving parts?

Signed,
NOLTT (never over look turtle talk)
 
Doc Stephenson

Doc Stephenson

Member
Thanks so much for the help. I thought I'd covered all the information and steps taken so far, but clearly I brain farted the name of the part when I was describing the problem.

Sven, yeah, I never even looked at the order or orientation of the plates. I just installed them in the orientation they come from Baker (thicker steel plate in the inside). Thanks for all the info. I'll take a much closer look at the plate set when I get it apart later. today. fyi, baker says they send them presoaked, but I soaked them in primer fluid anyway.

One note of fact, the pushrod is moving 3/8" when I squeeze the clutch. I'd be more comfortable saying 1/4" to 3/8", probably more toward 3/8", but I'll actually measure it today. When I was checking for the movement happening at all, that amount of movement looked fine. If this amount is way off from what it should be, then I've got bigger issues. Maybe a bent pushrod or something. I do not know. when I looked at it, it looked to be the correct amount of deflection, or at least the amount I would expect from a cable/ball & ramp.

fyi, when I get to the bike shop, i'll take some pics of the current state and the deflection of the pushrod. Anyone interested in some other pics? seems like everything (not work related) happens on Saturdays these days, but i'll try my best to get back to the bike shop asap and get some pics and take the carrier off. while it is possible something in the clutch pack is bent, but i'm pretty anal with alignment, torque specs, etc but i'll check. also just to let everyone know, I do own the shot manual for this bike if anyone needs to know something or something to look up to help, but wrt to the clutch, it's pretty normal. the clutch on this bike is very mechanical, so it's supposed to be easy right.
 
Doc Stephenson

Doc Stephenson

Member
Resolution update.

Took everything apart, left side and right side. I found the inner ramp was ½ way compressed. The first time, I was the one who took the clutch cover off and checked it out. I didn’t have any help at that point when putting it back on the bike, so it’s possible the pulling of the cable when mounting caused the ball/ramp to pull a little bit and collapse causing the problem found after reassembly to begin with, wasn’t corrected during adjustment, and the problem not fixed because of that. The 2nd time, another guy in the shop was working on the right side, checked my work out (he found nothing unusual), and put it back together. I was working on the left side that time. Problem still there, so the post to you guys for help. After that post, I did everything again myself, left and right sides. Took everything off, cleaned, inspected, etc. That’s when I found the problem with the clutch ½ way engaged. I didn’t find anything else wrong. So, I had someone in the shop help by holding the cable together while I put the clutch cover back on the engine. Made all the adjustments again. Time to test…

Now all is well!!! Tested in the shop fine, so I took the bike out for a test drive. All was great, no slipping in 3rd or 4th at any rpm. Burnout (small) trying to feel if the clutch slipped. No slipping and super solid. Idle, engage clutch, shift to 1st. RPM didn’t change and no drag in the plates I could hear or feel. Again, just what I wanted to hear.

If you want to pick for the 10 sec burnout, that’s fine. I already have a new tire waiting and the current needed changing anyway. I’ll do that later today. Don’t judge the method, this one is my bike, I can test the clutch my way. If you have a better way, let me know.

Fyi, if you care about the displacement part of this. I did the left side 1st and measured the displacement of the pushrod, dead on ¼ inch. I didn’t measure the displacement of the pressure plate when everything was together. In hindsight, I should have. Anyway, at that point, nothing “seemed” wrong, so I went to the right side and found problem. I can't say if the original problem was resolved with a good cleaning, or something with the clutch pulley, or a combination of both. Clearly, I just know that doing both did correct the problem. Thanks so much for the help.
 
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