about to lose my mind....clutch slipping - maybe

Popping out of gear is usually caused by incomplete or partial engagement, where the driving forces are mostly on the bevels of the dogs/cogs, especially when those bevels get rounded and longer. It can 'lever' the shift fork, and either bend it, or force the shift drum to rotate slightly. Some H*ndas would show up in our shop with worn/wallowed indexing wheel holes, the ones that ride on the 'star' pins, which would allow the shift drum to wander a little. This 'disengagement' issue was usually quite visible when inspecting the dog/cog faces, the shift fork faces, the shift fork slots, and sometimes the indexing wheel, star wheel pins (notching), shift drum guide slots (slight widening at gear positions), and shift fork pins (slight notching from shift drum slot.

But popping out of gear is completely different from clutch uncoupling/slip. Usually gear disengement is buzzy/rattly/violent, and clutch slip is a smooth feel. Clutch slipping, if done long enuff, usually results in discolored plates, and the fibers will feel a little harder and glazed when trying to indent with your fingernail. My smeller doesn't work anymore (too much chemo), but some folks could simply smell the fiber plates and tell if they've slipped/burned.

Is this old news for you guys, do you believe it's more of a clutch 'disengagement' than a gear skip-out?
 
TwoMany.....I dont perceive any buzzy/rattly/violence......it honestly feels/sounds just like you reached over and pulled in on the clutch lever while going down the highway.

Everything makes me believe its a "clutch" issue.....but Ive changed every single part of the clutch and it still persists.

It was NOT there before the 5th gear swap and it showed up immediately after the 5th gear swap. It persisted thru me changing every single part of the clutch, including the basket. I even completely swapped the transmission internals from another bike (but put the 5th gear OD back in).

I cannot wrap my noggin around why a gear on the other side of the case would cause this......but it seems to me to be the case.

I was really doubting myself until someone else showed up with the exact same problem.
 
Yep.....I had that printed and went thru it the one of many times.....nothing missing or out of place. Everything looked good in the "claw adjustment".
 
Here's another:

http://www.xs650.com/forum/showthread.php?t=143

I'm going nuts trying to find the thread that contains specs for total clutch plate stack-up thicknesses.
Maybe it's on another website or forum.
This is just to ensure that there is sufficient clearance between the mushroom and the pressure plate.
Using just a 'tablet' here, maybe you can find it...
 
I can second his statement. Feels as if you pulled the clutch in . I went through my whole motor this winter. No problems before rebuild . After rebuild and 5 th gear install . Same problem as OP. my shift forks were fine . Clutch assembly is perfect .
 
Here's an idea...... 5th gear dog engagement to corresponding gear.....torque applied to dogs.....mainshaft lateral movement....did you change tranny bearings? In this pic the middle gear on bottom shaft is the one moved by the fork (to the right for 5th I believe), if the shifting drum/fork is pressing gear/shaft assembly to the right, also the clutch hub is attatched directly to the mainshaft opposite the pressure plate. Vibration/friction with 5th gear dog engagement and loose bearings could be pushing the mainshaft to the right, while the clutch pusrod is still pushing on the pressure plate. When you back off the throttle, the dogs/gears move back to a neutral, wait..... fully engaged position:), and off ya go!

If/when you got the cover off (again:doh:), with the clutch still adjusted proper, pull the lever and watch the whole basket, release, and try and push it back in the case. Then, pull the plates and check inner hub/mainshaft endplay

.........Just an idea:wink2:........
 

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If/when you crack it open again, follow-up on NONclow's post. Check for any shaft and shiftdrum endplay, ensure correct thickness shaft washers in proper position. This OD 5th is in a lot of bikes. Could be a mfg error, but you could confirm that with both old/new gears in your hands. That OD 5th and clutch share the same shaft, gotta be something there...
 
Well I think I found the problem . After splitting the case . The dogs on the gears on 5th were rounded and chewed up a little bit . I am trying to up load a pic . Every thing was installed right . So I am going to replace the whole tranny . I had a extra one from a spare motor. I really don't know what is wrong with the gear but it was the problem.

So this gear just cost me a lot more than what it's worth!
 
Well I think I found the problem . After splitting the case . The dogs on the gears on 5th were rounded and chewed up a little bit . I am trying to up load a pic . Every thing was installed right . So I am going to replace the whole tranny . I had a extra one from a spare motor. I really don't know what is wrong with the gear but it was the problem.

So this gear just cost me a lot more than what it's worth!

strewth ....that doesn't sound good on a new gear does it.!

Looks like you may have found part of your problem but its odd that you didn't notice 5th gear suddenly jumping out of engagement ???:confused: I still think ,like most other posters that there is something else going on with the clutch .

Are these 5th gear sprockets being manufactured properly I wonder ?
My 5th gear has only done 18k miles over 35 years but there is absolutely no wear on the dogs at all !


I think all this cheap stuff from the far east is going to come back and bite us bad eventually as all the little manufacturers in the West who can't compete on price go bust and the skill , expertise and experience are lost along with it. Sad :(
Often the problem is simply that stuff isn't properly quality control checked
 
I've just reread this thread.
When a clutch is just starting to slip it is most noticable in the higher gears under hard acceleration at higher engine rpms. Like in fifth gear at around 5500 rpms and you open up the throttle and when you hit 6500 rpms the clutch slips.
As it gets worse it slips at lower rpms and in the lower gears.
Now in Arrons case it started slipping after Mike's fifth gear. If your clutch was just starting to slip then Mike's gear being just a bit higher gear the slippage will be more noticable.
I don't think your problem is the gears, there is something in the clutch not quite right.
When I rebuilt my clutch I used both my 75 clutch and an 82 clutch. Both slipped with the 750 engine. Rearranging all my stock parts in many different combos didn't help.
I sanded any color off the steels and roughed them up. It helped but not enough.
I bought heavier springs, Kibble White 70 lb. I replaced the worm, cracked. All these things helped a bit.
I finally got Forodo fibers.
My clutch works now. No slippage. Easy lever pull. two fingers.
Maybe those Vesrah fibers are not all that great.
I might try the Forodo fibers before I replace any gears.
Leo
 
My 5th gear has only done 18k miles over 35 years but there is absolutely no wear on the dogs at all !

Likely originals:shrug:, that were installed together. I think the new one from mikes w/ new (not yet abused:wink2:) dogs trying to mate w/ an older gear w/ worn holes. Improper initial fit causes binding that with constant torque starts to separate the dogs. Which causes bearing wear, and eventually, exssesive shaft endplay, which can be checked w/o splitting cases.

Check every "old" part of the system that gets 1 new part: fitment, clearance, preconcieved wear.

Think of it like a brand new chain and old sprockets.
Ditto XSLeo on (lack of) quality with Vesrah.
 
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My clutch was fine and assembled with new ( better) bearings from 650 central , new push rod, heavy springs, all washers in right place. No discolour on steels. No problems until 5 th gear . I am going swap out transmission with extra one I had laying around. Don't know what else the new gear has damaged. All my trans bearings were in great shape . No play , spun freely .
 
Ran my xs for the first time after making it into a bobber, clutch slipped, not horrible but slipped when you really got on it. Let off throttle she would settle back in.....repeat. I never opened the right case, so I thought it to be an existng problem. Figured I would replace clutches and friction plates. Did this, still slips. Pisses me off, I read every clutch thread available. XSLeo or retired gentlemen describes the stamping/manufacturing process with all of those smeared burrs on the exitside of the stamping.....well times 30 teeth times times 5 steel friction plates on a cast aluminium piece. Deburred all the friction plates, gave the clutch basket, where clutches contact, a ultra light sanding w/oil on the sand paper. Then wiped it all down, scuffed the faces of the friction plates, reinstalled properly. No slipping

When you feel those burrs, think about the 150 plus little hard steel knife edges with pressure on them trying to dig into the soft cast aluminium.......sanding then took time, effort, focus, and patience. If they did this at the factory we wouldn't be paying 8.50 for something that was made on the other side of the planet, they would be 25.00 a piece.

Just saying.
 
Two things to eliminate in this fault finding mine-field:

1. Is the clutch bearing washer in good shape? and in the right order in the washer, spacer, bearing sequence (apologies if I am teaching my grandmother to suck eggs on that one).

2. Is the shifter-shaft claw moving those gears correctly (that's operating the star-shaped assembly)? - if not that would strongly indicate the line TwoMany has been following, bent fork mechanism inside. The engraved circle pointing to ten past the hour on the star mechanism is fifth gear. Operate all the gears through from 1st, (20 past the hour) neutral (6 o'clock) to 2nd, 3rd, 4th and 5th (reach through underneath the carbs or another pair of hands with you). If you are lucky it might be a simple case of adjustment here to resolve the mystery slipping. It is always worth a try.

Good luck

Anlaf
 
Ran my xs for the first time after making it into a bobber, clutch slipped, not horrible but slipped when you really got on it..

I've recently done the same with my plates and basket. I didn't have a problem with my clutch but whilst the clutch is apart it has to be worth the investment of all the time and effort as you have shown.
Welcome to the forum by the way. :thumbsup:
 
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