Shifting issue identified, culprit found

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ponyfool

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I successfully split the cases and removed the main drive shaft, shift drum assembly, and transmission this afternoon. Upon inspecting the parts, I can clearly see damage to the shift fork and gear dogs. So far, there hasn't been any "holy shit, now what?" issues. It's been pretty straightforward. Let's hope I think that when I am putting it back together.

See for yourself:

Click Image to Enlarge

CASES SUCCESSFULLY SPLIT





DRIVE AXLE ASSEMBLY



DAMAGED SHIFT FORK



DAMAGED GEAR DOG



ANOTHER VIEW OF DAMAGED GEAR DOG (All dogs on this gear (2nd) have similar wear)



DAMAGED GEAR (WHERE DOG ENGAGES) and DAMAGED DOG



UPDATE: The job is finished. Outlined in this thread: https://www.fjrforum.com/forum//index.php?showtopic=106625

 
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I'm compiling a list of all the parts I need to order, and holy cow is it extensive. I wish they had an "Entire Engine Gasket Kit" instead of having to look up every freakin' gasket and O-Ring.

 
You're a brave man. Good on ya man for attacking the project. Are you going to go ahead and take the gearbox apart?

 
Very cool pictures, thanks!

I tried looking back over your earlier posts but I didn't see any explanation for what caused the damage... any idea as to the cause?

 
Very cool pictures, thanks!
I tried looking back over your earlier posts but I didn't see any explanation for what caused the damage... any idea as to the cause?
I'm told that typically a bent shift fork is caused by a high speed mis-shift (or multiple mis-shifts), abuse of shifter, a forced shift without clutch, and a few other. The gear dogs start to wear due to a bent shift fork.

I don't have any specific knowledge of any of those happening, but who knows. I loaned my bike to a co-worker for six weeks when I was out with shoulder surgery, but I have no tangible evidence to suggest he caused it either.

 
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I don't have any specific knowledge of any of those happening, but who knows. I loaned my bike to a co-worker for six weeks when I was out with shoulder surgery, but I have no tangible evidence to suggest he caused it either.

Wow, that's a bummer. Good luck in getting 'er fixed! Always makes me a little nervous to hear about things like this happening... I want to believe my bike is bullet-proof!

I know one thing for certain, my '07 FJR shifts smooth as butter compared to my old XS1100. That old bike was super notchy and got worse the hotter it got. Once you got used to it, it was fine. But when I hear folks complaining about how an FJR shifts, I have to smile!

 
So were the symptoms you experienced the typical ones: false neutrals, popping out of gear, etc? Are you going to replace all the forks and dogs since you're already in there?

 
I don't have any specific knowledge of any of those happening, but who knows. I loaned my bike to a co-worker for six weeks when I was out with shoulder surgery, but I have no tangible evidence to suggest he caused it either.
Stuff don't bend without force. I think I'd have a heart to heart talk with yur co-worker... :thumbsdownsmileyanim:

I can count the number of people I'd loan my bike to on one hand.

And every one of 'em would be fixin' my bike if it was screwed up.

I wish ya was closer to me, cause I get the feelin' your a good ol' boy and I wish I could help ya.

 
I'm told that typically a bent shift fork is caused by a high speed mis-shift (or multiple mis-shifts), abuse of shifter, a forced shift without clutch, and a few other. The gear dogs start to wear due to a bent shift fork.

I don't have any specific knowledge of any of those happening, but who knows. I loaned my bike to a co-worker for six weeks when I was out with shoulder surgery, but I have no tangible evidence to suggest he caused it either.

Wow, that thing must have really gotten hammered. I just did a track day on my R1 at Laguna Seca yesterday, and even as I was riding, I was thinking that I wasn't being too kind to the tranny. I always used the clutch but I wasn't too concerned with the niceties of smooth shifts and I didn't break anything. I'm thinking there was some major screw-up of a shift to cause the damage on your bike. Too bad.

 
You are so not going to NAFO...either you'll still be working on this or you'll burn up all your leave working on it until there is none left for the trip... :D

Make sure you get plenty of miles on the rebuild before we launch July 22nd!

 
Wow....reminds me of my bent shift forks on the harley. On top of that...reminds me of the broken tooth on the second gear of the harley.

Yeah, shifting without hitting the clutch will do that.....I guess.....hell, I don't know..........does it?

 
Good for you PF. You took the job on and you're doing great. Just get those parts and start putting it back together and we'll see you at NAFO.

 
Good job so far and I wish you the best of luck!

Thanks for the pictures. I been staring at the pictures for 30 minutes and still can't figure out how it works. :huh:

 
Good job so far and I wish you the best of luck! Thanks for the pictures. I been staring at the pictures for 30 minutes and still can't figure out how it works. :huh:
One of the best ways to figure it out is the way 'ponyfool' is doing it -- you don't necessarily need an FJR, though; almost any small motorcycle operates the same way (and, there may be considerably less stress for you?).

'odot': Wow....reminds me of my bent shift forks on the harley. Yeah, shifting without hitting the clutch will do that.....I guess.....hell, I don't know..........does it?
Just rolling-off the throttle will allow a 'break' in the power transmission and permit easy, safe, gear changes -- clutch disengagement isn't really necessary (but it does, essentially, the same thing).

Big boots stomping levers may have something to do with it? :( :unsure:

 
Did you give any thought to having the dogs undercut as long as you were in there? I've missed a few shifts and always thought that doing that would help.

Not that I'm gonna split the cases to do it, but as long as you're in there.....

Rancho

 
It would seem that a gear jumping sideways after a dog slippage would be where a shift fork would receive its worst abuse.

Is the groove in the shift drum assembly damaged when a fork is pushed sideways by a slipped dog gear? Does the fork guide bar get bent by the deflected fork?

A motorcycle transmission is an amazing crude mechanism. There's nothing there to help the operator -- no synchronizers, etc. The quality of shift is primarily a function of the operator's skill and to a lesser extent the operation of the clutch.

Are the dogs longer on a higher torque bike -- the gears are likely wider? Seems like a higher torque bike would be the most difficult to shift properly.

 
Much kudo's on ya Pony for tackling such a job as this. I would not do it myself due to lack of knowledge but could one ask if the Y.E.S program would have covered such a repair? Hope it all works out and your back on the road soon. PM. <>< :good:

 
Much kudo's on ya Pony for tackling such a job as this. I would not do it myself due to lack of knowledge but could one ask if the Y.E.S program would have covered such a repair? Hope it all works out and your back on the road soon. PM. <>< :good:
I'm told the Y.E.S. program MAY have covered it, depending on the service department since it is generally considered to be caused by "abuse" by said service departments.

 
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