Shifting woes - what's going on?

[Jefe]

Hello,

Something's wrong with my shifting and I can't figure out what.

Backstory:
I put together a 1979 engine with a new shift drum from ebay (the first got chewed up when the forks got jammed into it sideways)
Now, the shifting is screwed up - with engine turned off, it shifts through all the gears, but with engine on, I could go from N-1-2 and back all day long, but going to 3, it was almost impossible to shift back to 2 unless I turned the engine off.
I thought it might be clutch related, since I was getting all gears at some times but new springs and multiple adjustments didn't help (plates are well within spec)
Somebody suggested bent forks, which seemed reasonable. I turned it over and did a fork transplant with a set I had (I'm not sure which set were the originals).
This made matters worse!
Now, it only shifts between N-1-2 (still turned over); when I try to go higher, it just jams like it's locking up.
Anybody know what's messed up? Ideas on how to fix it?
Thanks in advance,
Jeff

[DGXSER]

Check that you do not have your shift forks mixed up. The left and right ones only go in a certain way, the tube that mount son the shaft is longer on one side than the other, and the longer side goes toward the center IIRC. Check that you do not have two number one shift forks in or vice versa and that they are in the correct spots.

[TopCatGr58]

Hey Jefe,

I am bothered just a little by your diagram of your shifting...N-1-2.

It should be 1-N-2-3-4-5.

Secondly, there is an alignment for the shifting pawl and the shift drum, the manual describes it, with gear shifter off, drum in the 2nd gear position, shift pawl in normal relaxed position, there are alignment marks on the side of the pawl arm and the shift drum...a little single line/hash mark, and they should line up with each other, and if they are not, then you adjust the shift pawl near where the shift lever attaches to move the pawl so the alignment notches line up. That could be another possible problem, once you verify your shift forks are correct and in the proper position.

But you say you can get it to shift thru all 5 gears with the engine off, I suppose your spinning the rear tire a little bit...needle to wiggle the gears while shifting.

You said when the engine was running that it wouldn't shift higher than 2nd, but did you have the bike on centerstand so rear wheel could spin a bit, and let out the clutch lever between every shift?

T.C.

[Jefe]

Thanks DGXSR and TopCat,

I think the mystery is solved.

DGXSR, following your advice, I went to double-check I hadn't put in two 1's or two 3's. I had them oriented right, but found I'd put in the old bad #2 fork, with a notch and a big burr on the follower. And it gouged out my new shift drum just like the old one! After sticking in a #2 fork and shift drum from a donor engine, I can sorta shift through the gears from 1 to 5. It does needs a fair amount of tire jiggling and shift selector wiggling like you said, Topcat, but I'm hoping it's only stiff because it's cold and not bathed in oil

TopCat, it was your dremel fix post that kept me from tearing it all down to split the cases - thanks, amigo.

I'll get my buddy to help flip it over again on Friday. What could possibly go wrong?

Thanks for your help, guys.

Jeff

[CatatonicBug]

I'll get my buddy to help flip it over again on Friday. What could possibly go wrong?

No need to flip it over if you don't want to. The whole thing can be done on the centerstand.

[Jefe]

Hello CatatonicBug -

I tried on a previous bike to do the 2nd gear fix on the centerstand, but needed a third hand or a prehensile tail to keep things from falling in my eye. I believe it's possible, but I'm not coordinated enough. If you can do it, my friend, I'm sincerely impressed.

And actually, I do need to flip it over now because it's currently upside down!

Jeff

[Jefe]

the sad story continues...

After getting no joy from replacing the obviously bad middle fork, I did Catatonicbug's centerstand surgery to replace the other two, and made some progress.

Now, I have all gears - which is great.

Not so great is that the shift drum doesn't always click into place right away, so that I can't shift at will, but have to tapdance a little sometimes before that dome-ended locating dowel slips into the valleys of that star-shaped cam. I know this is the problem because I noticed it when turning the shift drum before reinstalling forks. Foolishly, I thought it might heal itself when hot and oily, so I buttoned it all up and find the same issue.

I'm thinking of two alternatives:
1. Ride it and shift a thousand gears until it wears into place
2. Tear into it again to polish all wear marks out of that star-shaped cam (though I worry about changing tolerances or curves)

Any suggestions?
Thanks,
Jeff

[TopCatGr58]

Hey Jefe,

Did you check/verify the shift pawl and drum alignment before you buttoned it all up? The pawl may NOT be pushing/pulling the drum far enough/around if it doesn't have enough THROW..which is set with the alignment.

Another problem that occurs is that the shift lever spring gets weak, and folks report problems with Downshifting, because the spring doesn't pull the lever back up to the full return position which resets the ratchet on the shift pawl, and so folks "dance" on the shift lever until it finally bounces back up enough to reset, then they can downshift to the next gear. Instead of bouncing on it, gently slightly lifting on the lever enough to reset the ratchet without actually shifting back up a gear can then let them shift down thru the gears. Just wanted to add this in case you were experiencing more than just one type of shifting problem symptom.

T.C.

[rockman]

I've just put mine back together after the dremel fix/washer swap. What I find is I can get 1st and 2nd ok, but to go to 3rd and upwards I have to give the lever a little flick with my foot. Then it works ok and I can get all gears. The problem is only on upshifts, not downshift.

Sound similar to yours. I'm thinking weak return spring, but I'm going to try riding it about for a while and see if it loosens up. Only done about 2km so far.
Interested to see how you go with yours

Phil

[DGXSER]

one thing about these XS11s is that it takes a VERY FIRM shift to get them to go into gear. None of this flip the toe in the up direction and it will fly the rest of the way into gear stuff, you have to lift that shift lever ALL the way up and firmly each and every time.

[latexeses]

As fredintoon says: смены как российский трактор

[Jefe]

Thanks amigos - I think I'm getting some clarity.

Topcat, when I was hand-shifting it was easy to jump a tooth between pawl and shifter, but they were definitely dot to dot when secured. And the shifter lever snaps back into place just fine, so its spring seems fine.

DGXSer, the sensation I'm getting when it won't shift is like when you try to upshift from fifth or downshift from first - the shifter feels like it's got nothing to grab. After playing footsie with it until the drum clicks into place, it grabs just like it orter. And I shift with a firm and manly foot - no pussyfooting for me!

The manual calls the star-shaped cam piece a stopper plate; the hollow domed dowel with the spring inside that hits the stopper plate is the shift cam detent. If that spring is responsible for snapping the drum into position, maybe rockman is right that a spring's the problem, though not the shift return spring. Can anyone tell me if the drum spins freely before the detent is fitted? I didn't think to try it before.

If that spring is flaccid, then, and I can't find any spring Viagra around, I suppose I need something stiffer in that detent hole.

Can you just order a spring to size? Failing that, I do have another detent assembly around and I suppose I could mike the springs and use the longest.

the plot thickens...particularly with Russian cropping up. What's "smen kak rosseiskei tractor" mean?
Jefe

[DGXSER]

I think the statement is "they shift like a Russian Tractor". Just another way of saying they are loud, clanky, notchy and no pussyfooting on the shifts.

Once i is in gear, does it seem to drift in or out when you get on or off the throttle? That pin is there to hold it in gear, I would think more so than to "finish" the shift.

If you need another detent and spring I have one laying around here, or did the last time I noticed it anyway.

[bikerphil]

Jefe, with the bike in 2nd gear, are you sure you have the two marks on the shift drum and the pawl lined up? The photo below shows the marks not lined up because the bike is in neutral. They should line up in second for proper shifting...

[Jefe]

Thanks for the brain cycles, guys.

DGXSer - it never seems to drift from the selected gear, no matter how I goose it, so the shifting seems to be finished as far as the gears are concerned.

I appreciate the offer of a detent - I may take you up on it if I can't find mine. You may be right that the detent isn't finishing the shift by clicking into the notches of the stop plate, but I'm having trouble understanding what else might be doing it. Do you have any other ideas?

Bikerphil - thanks for pointing out that alignment of the claw and the drum. I never checked it so I don't know for sure. But I get all gears sometimes, and the only alignment mentioned in the manual was the dots on the teeth that the pawl pushes up and down. For that reason, I'm thinking it's probably where it should be, but I'll only know for sure when I get annoyed enough to take it apart again.

Fortunately, I've got plenty of ways to put that off, with four other pieces of two-wheeled garage art that don't run either.

Jeff