Only 2nd, 4th, and 6th Gears Working | GTAMotorcycle.com

Only 2nd, 4th, and 6th Gears Working

stnd

stnd

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Solved one problem only to be rewarded with what i presume will be a much worse nightmare.

While out on a casual ride with a passenger last night all of a sudden at a light my first gear would not work. I can rev it and release the clutch and the bike will not move forward, nor stall. I am able to switch between gears, but only 2nd, 4th, and 6th engage and really feel like it shifts gear, while 1st, 3rd, and 5th do not really kick into gear and no power is delivered to the sprocket.

There are no loose metal noises from the engine, and I was able to make it home in 2nd without issues. Only once home did i test all the gears and realize i had 4th and 6th as well.

My guess is one or more shift forks is bent, or the shift drum is damaged in some way, but I wanted to check on here if anyone has experienced something like this. I don't look forward to splitting the cases, but if that's what it takes then it will be done.
 
Oh boy, that sounds like a bugger. I'm not sure what bike you have, but maybe try pulling the right side cover and clutch and see how the shift mechanism is working, before you decide whether to split the cases. Maybe you'll be lucky, and it will just be an issue there.
 
Make, model, year please.

Offhand I have a funny feeling that the shift drum has come adrift and is no longer properly located end-to-end. When it's trying to push the shift fork left (for example) it's pulling itself right instead. The other gears work because the shift fork is being pulled instead of pushed (for example) - or it may be the other way around.

Three simultaneous bent shift forks all in the same direction ain't gonna happen.
 
Minor digging suggests KTM 690. Correct guess? (Same bike you're having other issues with?)
 
Brian P said:
Make, model, year please.

Offhand I have a funny feeling that the shift drum has come adrift and is no longer properly located end-to-end. When it's trying to push the shift fork left (for example) it's pulling itself right instead. The other gears work because the shift fork is being pulled instead of pushed (for example) - or it may be the other way around.

Three simultaneous bent shift forks all in the same direction ain't gonna happen.
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2009 KTM 690. I haven't had time to research yet and do not have experience with the transmissions other than a feq quick videos demonstrating how the drum moves the forks around. It is interesting that 2nd, 4th and 6th work perfectly. and 1st, 3rd, and 5th are not.
 
Three of the gears will require the shift drum to pull a shift fork to the left, and the other three gears will require the shift drum to pull a shift fork to the right. If something has come adrift which allows the shift drum to move around, it could cause something like this to happen.


Check whether bolt #24 is secure ... It clamps the indexing part of the drum (26) to the part that moves the shift forks (27) with the bearing (also labeled 26 LOL) clamped between them.

It should be accessible if you take the clutch cover off.
 
Brian P said:
Three of the gears will require the shift drum to pull a shift fork to the left, and the other three gears will require the shift drum to pull a shift fork to the right. If something has come adrift which allows the shift drum to move around, it could cause something like this to happen.


Check whether bolt #24 is secure ... It clamps the indexing part of the drum (26) to the part that moves the shift forks (27) with the bearing (also labeled 26 LOL) clamped between them.

It should be accessible if you take the clutch cover off.
Click to expand...

Thank you Brian. I will look into that. As mentioned it was a fairly tame ride, and there was no 'event', it just would not work in those gears anymore. No grinding noises.
 
Brian P said:
Three of the gears will require the shift drum to pull a shift fork to the left, and the other three gears will require the shift drum to pull a shift fork to the right. If something has come adrift which allows the shift drum to move around, it could cause something like this to happen.


Check whether bolt #24 is secure ... It clamps the indexing part of the drum (26) to the part that moves the shift forks (27) with the bearing (also labeled 26 LOL) clamped between them.

It should be accessible if you take the clutch cover off.
Click to expand...

Do you think this is the part?

24eyvlj.png
 
Yes, that's the one. Hopefully you can get to that without taking the clutch basket off.
 
Brian P said:
Yes, that's the one. Hopefully you can get to that without taking the clutch basket off.
Click to expand...

Had a chance to look at it today. Unfortunately nothing seems out of place. After putting it back together I started it and tried the gears again, and the gears that don't work you can definitively hear some very mild clunking inside. Sounds like something which is fixed but not exactly in place.

Any other hints before I take the engine out. I did try kicking it into gears just in case something needs to fall into place but that didn't work.

2ebec5e.jpg
 
Borescope or fiber optic inspection :| you might get a break and at least spot an obvious problem, although I expect a complete tear-down is in order.
 
stnd said:
Broken countershaft. Wonder if a tight chain and a passenger could have caused this.
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Ouch! Over-tight chain should have trashed your swingarm and axle bearings first :|
imho That failure should have never really happened unless it was trying to engage 2 gear ranges at the same time, maybe keep searching for another issue.
 
add: a quick search of 'KTM 690 broken counter-shaft' suggests that you are not the only one to experience the problem, I smell a power train warranty claim.
 
Anyone ever come across small springs like this during engine disassembly? I cannot find any springs like this in the parts catalog, but they did seem to fall out after I removed the oil pumps.
 

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stnd said:
Anyone ever come across small springs like this during engine disassembly? I cannot find any springs like this in the parts catalog, but they did seem to fall out after I removed the oil pumps.
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Just a general note for posting pictures as this isn't the first time it has come up. Try to include something in the picture for scale (coin, ruler, etc). It helps people narrow down the possibilities.
 
GreyGhost said:
Just a general note for posting pictures as this isn't the first time it has come up. Try to include something in the picture for scale (coin, ruler, etc). It helps people narrow down the possibilities.
Click to expand...

Fair enough, I agree it can be misleading. It's the only pictures I have on me. The diameter of those springs is about 3/16". very small. I had just finished taking out the oil pump impellers and either spaced and didn't look inside or they were in the rags i was using from before. They just look so inadequate to be inside of an engine, but I have to make sure.
 
bitzz said:
Look at the pressure relief valve in the oil pump.

You may be missing a ball bearing too.
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That was something I considered, but it was strange that there were two. Now that we know the size, I am even more suspicious of that use. I haven't had an oil pump apart on a bike but I know the oil pressure spring on the mini is close to 1/2" diameter and much stiffer than those look.

EDIT: maybe you are talking about the relief for a clogged filter, that is plausible (although again I am surprised there are two).
 
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