New to me 07 yz250f

Going to be getting my hands on a 07 yz250f for a great price.

I race moto and desert and have always been a two stroke guy, this is my first four stroke.

Owned a drz400 before but that is all the experience I have with a thumper so I have a few questions.

The bike looks like it was an ex race bike. It has lots of aftermarket stuff on it and looks like she's got 100+ hours on her at least. The head was supposedly redone recently.....

I am a person that like to ride the same bike for years, my last bike was a 99 rm250 that I had for 6-7 years. I'd like to do the same with this thing!

So, what should I do to make sure she lasts a good long time?

I plan on riding it a couple times to "feel" her out before I do anything.

Any and all tips and tricks are welcome!

I'm excited about my foray into the 4 stroke world!

4 strokes are good bikes. as long as you maintain them properly it will last a while. just keep the oil fresh and the air filter clean and it will treat you good. just be carfull with that 07 jut becuase the owner says it has a new head dose not mean it actually has one. if it starts easy ang runs smooth without any wierd noises or alot of backfiering it should be good. i have an 09 yz250f with a little over 150 hourse on it and i have had no problems with it.

Thanks for the reply. I'm thinking I'm going to open up the motor and do an inspection after I ride it a couple times just to make sure.

I'm pretty excited about the bike, I've always wanted a 250f! I hope the deal goes through!

I also just bought a yz250f (08) and was a two stroke guy before. I'm really happy with the bike. Sadly 4 strokes are higher maintenance. Oil changes are even a pain in the ass when you are used to doing them on 2 strokes.

You'll find the bike much easier to ride.

If you are going 4 stroke I do recommend Yamaha. I've been riding/racing for over 10 years now and seen many bikes have catastrophic failures, but very rarely on Yamahas. 

Deal went through, bike is mine!

Turns out it was an 06, bike it's in great shape!

I pulled apart the carb and the slide and body have only small amounts wear on them, the intake boot and head were totally clean!

I'm guessing from the looks of the parts the bike has more than 50 but less than 100 hours.

Drained the oil and it wasn't bad. Has a stainless oil filter and there were some very small metal flakes. I'm not concerned

Still has the stock brake pads but they are low

I've got the carb torn apart and soaking in a Jug of pine sol

Being that I got the bike for FREE, I am one stoked dude!

I threw 1250cc of mobile delvac 1300 15/40w in it and can't wait to take it out.

I'm going to put 2-3 rides in it and then I'm going to pull the head and cylinder to check the crank, piston and valves.

I will update this thread with my findings!

Can't beat that price!  :ride:

Pulled the carb out of the pine-sol and reassembled.

Checked the valve clearance and everything was in spec.

Took the bike for a spin.... Runs awesome!!!!!

I'll post some pics tomorrow. I am very very stoked :)

snapped some pics of the cam chain and crank sprocket. 


from the pics im seeing on here she looks GREAT!!!!


gonna ride it at the track tomorrow, ill post some pics then also.


ordering a cam chain tonight, just to be safe!









I'd check the valve clearances while you put the cam chain on (when you get it)...i mean you're that far...might as well. But remember you will need a set of tapered feeler gauges! Also, if you have the coin, and the valves seem alright...may just wanna do a piston/rings, or least an inspection of the cylinder and piston and a set of rings. If it has THAT many hours on it. Piece of mind if nothing else, and not that expensive.

Nice work. How'd you score that for free?? 

Nice "head shots", how about the rest of the bike. :ride:


You had me worried at first. "new to 4 strokes and bought a high hours race bike". I was afraid this would not turn out well. Glad you like it so far. Yami is the best of the 250fs for durability. Sounds like you've got it down, pull the head and cylinder, check valves, replace Tchain, rings and piston if needed. Don't forget to replace the Tchain slider too. Check lower end bearing. Should be good to go. I bet you'll like it. They are super fun bikes.

To add an update to this thread-


So far i have replaced the piston and inspected the crank. absolutely zero play in it.


had to shim the center intake valve.


Thing absolutely rips. have 13.5 hours on it since i have gotten it. Probably the most fun bike ive owned. 


Mostly been riding mx at zaca station, really fun to ride the hell out of.


When i hit 50 hours i am going to build a complete stroker big bore for it. Ill make a build thread when i do it.

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