1996 YZ250 has shifting problems won't shift past neutral

[stevens96yz250]

Hello I have just joined this forum because I am a motorcycle enthusiest and have recently broken my 1996 yz 250.

Here is my bike's transmission symptoms, I was wondering if you could advise me on how to examine this transmission before I tear it down. I think I have to split the case.

The bike currently wont shift past neutral into 2nd. It used to ride fine and shift through all 5 gears. Some rides I would notice my bike almost hitting a false neutral. I went on a long ride, (trails) and at the end of the day just before I loaded it up for home it would not shift into any other gear then 1st, or neutral.

The Shift shaft had been sloppy since I owned the bike and so I had had some issues shifting as the stock aluminum shifter was slipping and stripped.

I have since bought a steel replacement and it no longer slips.

I recently bought the Clymer repair manual for my bike as I see some work ahead.

Thanks in advance for any help.

Has anyone had any of the problems described and if so what was the cause.

[linustitus]

I had part of a gear break off and knock a shift fork off the drum on my 99 YZ250 that made me unable to shift past second. Could be something similar but I'm sure someone else has further insight.

[davidl9999]

Bent shift fork(s), damaged selector, chipped gear teeth. Pretty much the usual thing. Yep, you'll need to split the cases.

Replace any shaft that is worn or isn't straight. Look for parts that don't quite fit right (loose or tight). Replace anything that's funky.

The steel shaft was a good call. The Al one gets thrashed pretty easily.

Good luck!

[Jayray23]

I am currently having a problem although not quite sure if its me or the bike. If i shift quickly from 1st to 2nd it will sometimes just slip to neutral. Dunno if this is a similar problem this happens to my YZ 125 2006.

[davidl9999]

It's a similar problem assuming it's not a shifting technique issue.

Just a quick note: I hate splitting cases. Checking that the clutch is properly adjusted and fully disengages might save some time wrenching inside the tranny.

[stevens96yz250]

Thanks I wll be starting the work this weekend and Ill keep you posted.

[stevens96yz250]

just removed engine from bike, the shift shaft is bent downwards, I have ordered a new one but am toying around with opening it up and having a look.

[davidl9999]

Can't hurt. Glad to see you making some progress on fixing it.

[stevens96yz250]

Yeah its nice to get around to the bike, we just bought a 94 cr 125 for my girlfriend and that's motivation to fix it even faster, so we can both go riding! in the meantime I can teach her how to ride. I will post some transmission photos soon, should have it apart by Saturday!

[stevens96yz250]

ok engine is apart, cyl head removed. All apart except for the bent shift shaft is not sliding out towards the clutch side. so far no huge metal shavings or damage. One of the gears appears to be chipped. Should I cut the shaft off from the inside or bent side or should i try to straighten it out first and then slide it? I dont want to damagae anything.

[davidl9999]

I'd try to bend it without stressing the case. If that doesn't work, I guess hit it with a dremel and cut it off. A damp (oily) rag can help catch metal shavings, but you'll still have to be careful to clean all that crap out if you cut it.

[stevens96yz250]

ok I went to the shop just to confirm and they said to cut it off on the shifter side, I did and then used a dremel tool to grind away the bur and bend in the shaft so it could pull out, at this point I now have slid the shift shaft out and have the whole engine stripped to the flywheel. Tommorow morning I will have the flywheel removed, and then split the case.

The sooner I get in there the sooner I can order the parts.

Now I have looked in on the gears and already notice a few broken teeth! It seems I might need a whole new transmission set.

Just curious why would a tooth break off the gear/s?

I have owned the bike for only 8 months and never really had trans problems until last ride.

[davidl9999]

Now I have looked in on the gears and already notice a few broken teeth! It seems I might need a whole new transmission set.

Just curious why would a tooth break off the gear/s?

That's pretty common. Shifting without the clutch, bent shifter fork(s), anything out of alignment, and just normal wear and tear will cause gear teeth to chip. It's one of the reasons to stick to the factory oil-change interval and cleaning the screen - looking for large flakes and magnetic chunks (imo). I haven't seen them break (as in completely losing a tooth) unless something majorly wrong happened to the tranny.

[stevens96yz250]

Yeah the bike is new to me and I guess its great to go over the bottom end as I am keeping it for a while.

I have just split the cases, they came apart fairly easy. There are only two teeth missing on one of the gears, but the metal that was flying around inside the transmission has chewed up almost all of the gears. I also noticed that the clutch release lever bearings were toast and that it didn't move smoothly at all. So now that Im in here I am going to replace one rough bearing in the trans as well.

So this is common?

I think it is damaged because the shift shaft was stripped and that made the transmission miss shifts and break my gears. I have learned that if the shifter

isn't working get it fixed or it can take out your gears. I was doubling alot on the bike up and downhill and everything contributed to it.

Thanks for the input David and I'll keep you up to date.

Do you know where I can find a reference chart for my transmission? or will the bike shop know best.

[davidl9999]

Anytime, Steve.

It's common in the sense that bike shops stay in business because of this kind of thing. It's not common in the sense that every bike is going to do it, but most (if not all) bikes will shed some metal and grind the sides of the gear teeth a bit - it's just the nature of the beast. The way I see it, if you own enough bikes, one of them is bound to break in a big way.

The manual has an exploded diagram of the tranny and how the gears go together.

http://www.yamaha-motor-europe.com/community/service/manuals.jsp

crap, that doesn't have the YZ 2-smoke...?

If you don't have the book, you can get a download here for $16:

http://store.payloadz.com/str-asp-id.106342-n.1992-2006_Yamaha_YZ250_Service_Manuals_Collection_247_74_MB_Other_Files_102-end-detail.html

I expect that it's fine, but you might want to order the real deal from your local shop. And as always, it might be worth a call to the TT store to see if they can hook you up with one.

Just a thought - if one bearing is rough, the others have been running in gritty oil too. You might want to just bite the bullet and replace them as well. Don't forget fresh seals. No guarantees, but I'd personally hate splitting cases again because "I shoulda, I coulda..."?

Good luck again on your tranny. A lot of riders don't bother to take the time to do this kind of work.

[stevens96yz250]

Thanks, yeah I bought the manual fromt the dealer, it was a good 30 dollar investment, splitting the case is the easy part, waiting for ordered parts to come in is hard. I just learned that my trans is the same from 95-98 and I am going to buy a whole set of gears as mine have some considerable wear, and the dealer wants about 100-140 per cog! I have found a whole set for as low as $67 plus shipping on ebay.

[stevens96yz250]

just found out 4th gear needs to be replaced, as it has a few chips and cracks...........3-5 days until the rebuild starts. I was just going to use it but re-thought it and decided to do it right.

[stevens96yz250]

I have one question, on the clutch push rod, should there be a ball on either side of the rod? one against the clutch release lever and one against the clutch valve looking think that pushes the basket.......the manual only shows one but the rod has a round indent on both sides for a ball perhaps?

thanks in advance

[davidl9999]

Just the one ball on the clutch side of the rod.

But...

Isn't the rod convex on the ends? I thought that the actuator pushed on a rounded (outward) point on the rod, and the ball spun on another convex surface. Here's a pic (although I think that you have one)...

http://shop.thumpertalk.com/oem.asp?partcategory=28202&manufacturer=6&category=3&year=1996&model=719

[stevens96yz250]

thanks, just wanted to confirm, yeah that makes sense there is only one ball. I ordered my 4th gear today and should have it 3-5 business days! more time to clean and go over the bike I guess. What bike do you ride David?