My first YZ experience. Mixed emotions...

So, last week I decided to sell my CRF250 and CRF450 and cross over to the yamaha/ 2-stroke lifestyle. I bought an 05 YZ250 for a reasonable 2800 bucks for how clean it was, and decided to save the rest of my money for my remaining years at college.


Previous steeds (good riddance to that blasted 250!!):


I took it out the next day (Friday) and fell in love with the smells and power of the bike in the woods. It was a freakin' BLAST compared to my 450. Unfortunately, an hour into my ride, after a rocky section I seemingly had lost my first gear. It would just slip and buck under power, so I just blasted back to the truck in 5th gear on the fire roads, very disappointed with my recent purchase. So that night, I cracked the cases, and this is what I found:

This was 1st gear:


This was the 5th gear "dog gear" (why do they call them that?):


And this was the corresponding shifty forky thingy:


Heres an view of my engine internals... reminds me of one of Dirt Rider's long haul wrap-ups:


I was really surprised and slightly pleased to see the bill for this overhaul was only about 180 bucks including new gears, fork, and gaskets. I'm still waiting for the parts to come in, and can't wait to hit the trails again! Any advice on getting this thing back together? It feels just a little bit overwhelming at this point...

While you remember what goes where, bag and label your hardware so that you don't get it mixed up.

Use loctite where your suppose to, don't where your not.

Torque specs are important.

As overwhelming as it may feel, when its going back together everything pretty much falls into place and shouldn't be to challenging.

If you get into a bind, parts fiche and manual can be helpful...especially if the PO or previous mechanic forgot a shim or clip here or there.

May want to loosen that chain up while your at it.

May want to loosen that chain up while your at it.

...I was waiting for that one. I'll get to it as soon as I find my swing arm in my parts pile. I'm redoing the suspension while I have it apart.

nice bike. are you going to do the crank bearings while your in there? on an 05 you might as well.

My 2 cents.... since you've the whole bike apart, double check the wheel bearings and all the suspension bearings....

They aren't that expensive to replace, if needed. I'd also look at replacing the main seals at the crank.... they don't fail that often but since you've got the bottom end apart, might as well change 'em out.

All the rear end bearings were supposedly replaced, and they feel tight, I just checked the front wheel and it did have a bit of play. thanks for the advice guys. I think I may get the crank bearings changed out as well, only 50 bucks for some serious preventative maintenance.

I like what you paid for it, I'm going to be selling one this fall that will clean up to like new.

Put in WR426F gears. 3-4-5 are a direct fit!

I like what you paid for it, I'm going to be selling one this fall that will clean up to like new.

The aluminum frame YZ's seem to hold their value very well compared to other brands, they're hard to come by in Oregon as well! They get snatched up fast.

+1 on Shrubs recommendation.. 3-5 WR gears are an amazing upgrade for the bike.. Really spreads out the power.. Also, second the recommendation on doing the crank bearings while you have it apart.. Cheap insurance..

As far as the failure, Id speculate that the tranny was already well worn by the time you bought it.. So dont bag the YZ too much, they are great machines :ride: I got four seasons out of my 05 and on my fourth season with my 07 with minimal issues :thumbsup:

same thing happened soon after I bought my 06 --it had been raced hard and I got a great price.

Fixed it and have had no problems since --as noted, while your in there replace bearings and anything that looks worn and when you get it back together you will be a happy man.

I stayed with stock gearing but the WR idea is a good one for trails --I may still do it at some point.

The WR gearing sounds like a SAWEET mod to do. I think I might have to do it for a winter project. As for the crank, I just ordered a new set of bearings and seals as well.

what was wrong with the crf250 you had ??

How would the wr gears be for serious hare scrambles. I'm running 15/50 which is great for top speed but in really technical riding is alittle tall.

what was wrong with the crf250 you had ??

The crf250 was just a bike I bought cheap (not running) "in need of a valve adjustment". The valves were in spec, so I did some detective work and replaced the rings. After that it ran great and I sold it for some profit. I didn't trust an 05 crf250's valvetrain to ride one myself.

i kind of didnt either, but i still ended up with a 05 crf250

I was really surprised and slightly pleased to see the bill for this overhaul was only about 180 bucks including new gears, fork, and gaskets.

Where did you manage to get all that for only $180? I need to replace the gears on my 125 and just 2nd gear is like $150 from

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