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tranny help

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ok guys here we go, i have an 01 yz 250, i forgot to tighten the sprocket bolts and that is setting me back a new hub and sprocket. not a big deal to me now, lol i found a back wheel to use for the race and put it on, started my bike and put it in first gear, it made the sound like you were at a really high rpm and jamed it into gear, rode it to find that first gear is my only gear, i pulled the clutch hub out to inspect the shifting mechanism, it was fine so im guessing that i have a broken shift fork, i pulled the drain plug and found a small chunk of metal on the magnet, being on a tight budget i pulled the motor out already and am planning on splitting the case to find the culprit. does anyone have any idea of what this is, and how hard is it to split the cases? do i need a case puller? thanks for all the help ill keep you updated.

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Could be the nub on the shift fork that follows the guides on the shift drum.

Picture of it?

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i can try to get a picture tomorow. i have not split the cases yet so i cant see the shift forks.

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I didn't finish reading your questions, sorry.

To split the cases it's a big job, but when you do it a couple of times it's not so bad. It looks intimidating but if you understand how the parts work, and remember how they are placed throughout the case, it's not a huge deal.

With the top end removed,

To sum it up briefly, you need to remove the flywheel, this is pressed on and requires a puller to get off. Stator comes off next held in by 3 large phillips screws. You need to remove the clutch side case half, which is just bolted on. Water pump and all that can stay on this case half, does not need to come off to pull off the clutch case. You'll be exposed to the kickstart, idler gear, clutch assembly, etc. You need to pretty much remove all of these parts, including the shift stopper, the shift shaft etc.

Clutch hub is hard to remove without a tool, people tell me that you can use a strap wrench and position it onto the peg of your bike, or you can use a clutch holding tool, a set of vice grips that works in a similar fashion. With the hub securely positioned, you can now remove the clutch hub nut (27mm) with a breaker bar, you may need to use a pipe on this breaker bar as well, the nut is on VERY tight.

After that, remove the engine from the bike, remove all the case screws, and now you can start splitting the case with the case splitting tool. Basically your going to split the case from the crank, the crank itself is pressed into the bearings which are pressed into the case.

I've left out a shitload of small details, and I highly suggest getting a service manual to do this. I read mine about 15 times before I started to remember how things all go together, and it doesn't seem like a very challenging job anymore, where at first it seemed way out of my league.

There is a video that shows you how to do it on youtube here

Watch that a couple of times and get it through your head, then read the manual until you understand it. When you've done that, start ordering the tools and you're pretty much ready.

Good tip is to keep all the bolts screwed back in where they came out of. Some bolts have to stay out because they hold the case together, but for example the shift stopper bolt can go back in when you've taken the stopper out, etc. Do this for all parts that do not interfere with the case splitting process and you'll have that many less bolts to worry about and where they go etc.

For case bolts, finding the right length might make you think you should draw out where each bolt comes from, but a good tip is this. When you drop in a case bolt, if it sticks out about half an inch, it is the right length, if it bottoms out or sticks out huge, then it is not. I think the video shows this, can't remember.

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