Transmission output shaft replacement

[Mulholland]

http://faq.ninja250.org/images/d/dc/TRANSMISSION.png

From that image, you will be looking at part 13128 and 13270. The previous owner of my new to me 03 ninjette busted chain, presumably from having it far too tight and having a clip master link installed, and managed to gnaw off a few teeth from the output shaft. I just wanted to confirm the repair would require full tear down of transmission when I get around to fixing it, correct? Or can I get to the snap rings holding it in and remove it without full engine R&R? It doesn't seem to affect riding at all at this point, ran it up through gears with load on it and strobe light, doesn't ever lose tension or wobble or jump from where the teeth rest currently, despite the 13270 teeth being fairly worn, the sprockets and chain are new, so as of now I'm not terrible concerned by it, but being me, I will repair it some time, just want to enjoy the bike some before I do that extensive a tear down.

Anyone who has experience with this they would like to contribute is greatly welcomed.

[alex.s]

you'll have to drop the engine, flip it and remove the bottom case. you wont be able to get the output shaft out otherwise. would be nice, but not gonna happen. you're going to need a clutch hub vice to be able to get the clutch hub off so you can remove the oil line to split the case... i think its different on pregen so take that with some salt. make sure you clean up your case mating surfaces nice and clean before you put it back together so it doesn't weap oil. also its a good idea to replace those roller bearings if he did damage to the shaft... those bearings are probably toast as well.

[Racer x]

like Alex said . Pull the engine flip it over and remove side covers and case bottom. There are bolts everywhere top and bottom so if you do it be careful. The case splits easy. If it does not then there is a bolt. You have to clean everything really well and use honda bond or the like to seal it.

You can get a trans on e bay for 30 bucks these days.

http://www.ebay.com/itm/KAWASAKI-NIN...d6958d&vxp=mtr

[alex.s]

oh yeah don't forget about the bolts under the oil filter. those drove me crazy until i found them. dont force anything. it all comes apart pretty easily and cleanly if you are doing it right.

[Motofool]

Originally Posted by Mulholland

.........The previous owner of my new to me 03 ninjette busted chain.........., and managed to gnaw off a few teeth from the output shaft........

Are you sure that damage is important?

The sprocket was covering the section of the shaft that matters.

Could you show a couple of pictures?

[Mulholland]

the damage isn't entirely superficial. The new sprocket cured any issues, however only 1/2 to 2/3rds of them are engaged into splines in all honesty. I am not truly concerned about it, with the exception of increased noise from the wear maybe... no real failure mode unless the rest let go (which I can't see happening without another massive amount of trauma)


It has a cover over it, I will likely ignore it forever and ride it just fine, but if/when the time comes, was just wondering if full R&R was required as I assumed.


Thanks guys

[Motofool]

I see, I thought it could be something just cosmetic not worth the effort.

If the damage to the shaft is more than superficial (affecting any diameter smaller than the valley of the splines) or creating deep cuts or cracks, then you will need to replace the shaft as soon as possible.

That shaft works under cyclic load and, if damaged as described above, it will fail by fatigue:

http://en.wikipedia.org/wiki/Fatigue_%28material%29

I had an output shaft breaking up while riding that ended up in a nasty fall.

The sprocket got jammed under the cover and it completely stopped the rear tire.

[alex.s]

output shaft failure is not something fun to experience.

if the splines were damaged by chain stress, the bearings inside are also damaged. if you wiggle the output shaft, you may notice it has some play (if the bearings are bad)... it should not have any play.

[TonyKZ1]

Yep, I've got one engine that has a similar problem also. My countershaft would move in/out a little bit, it still worked but made noise. I was basically advised to replace the engine, so I ended up replacing it instead of tearing it apart and replacing the countershaft & bearings. I kinda hated to do that as that was a better engine than the one that I replaced it with. But I've still got that one so maybe sometime I'll tear it apart and replace it...
Tony

[alex.s]

moving in and out a few mm isn't an issue. moving forward/backwards/up/down indicates the bearing has failed

[Racer x]

Originally Posted by TonyKZ1

Yep, I've got one engine that has a similar problem also. My countershaft would move in/out a little bit, it still worked but made noise. I was basically advised to replace the engine, so I ended up replacing it instead of tearing it apart and replacing the countershaft & bearings. I kinda hated to do that as that was a better engine than the one that I replaced it with. But I've still got that one so maybe sometime I'll tear it apart and replace it...
Tony

Hang on to it. The trans replacement is less than 100 dollars