Please help id this yz 25p

[Scottwr12345]

Was under the impression my bike was a 2000 yz 250, ive searched the entire bike and can only find a few numbers below the counter shaft and on the cylinder, any yz experts out there please help me identify this bike!! 4XL 00 Y-1  is the number below the countershaft and 4XL 10 is on on cylinder.. thanks guys!

[MaybeMe]

No VIN? Should be on the steering stem on the right side, in between the triple clamps?

[S.O.A.N.Z]

4XL is 97 & 98

 

[YZDOC]

4 hours ago, S.O.A.N.Z said:

4XL is 97 & 98

 

Was going to say thats 98 head, not sure how far back that PV went. 

[CaptDan]

- Cylinder (power valve cover) and right-side case cover appear to be '95 - '98.

- Carb is from '96 - '98

- Swingarm looks like 1999 - 2001.

- Airbox (white) and square-tube (aluminum) subframe is 2000 - 2001.

Starting to look like a pre-1999 motor in a post-1999 frame.

Going through parts lists can help identify various pieces.

[Motox367]

It's Frankinhama 

[Scottwr12345]

Jesus christ i had a feeling it was a different frame to engine.. just dont want to go buying the wrong parts for it.. already bought the wrong countershaft sprocket :/ theres no vin anywhere i can find im guessing the frames been resprayed at some point.. thanks guys.

[Scottwr12345]

One other thing, given the amount of butchering errmmm work done to this bike... whats the best way to measure the bore to find the right size piston? Thanks again everyone really appreciate the help.

[MaybeMe]

12 hours ago, Scottwr12345 said:

One other thing, given the amount of butchering errmmm work done to this bike... whats the best way to measure the bore to find the right size piston? Thanks again everyone really appreciate the help.

Caliper at various points of the bore. Also make sure it is not out of round.

[CaptDan]

14 hours ago, Scottwr12345 said:

...theres no vin anywhere i can find im guessing the frames been resprayed at some point...

The frame's VIN is on the steerer tube, on the throttle side. If the number has not been thoroughly removed, it should still be discernible - even under powdercoat. Use a bright light - or sunlight - and look carefully. The number is stamped, so there will be deformations in the steel.

The non-floating front brake disc (and other clues mentioned earlier) indicates the frame, bodywork & running gear (if original) are 2000.

http://www.partzilla.com/parts/search/Yamaha/Motorcycle/2000/COMPETITION+-+YZ250M1/FRONT+BRAKE+CALIPER/parts.html

The good news is the same piston fits both '97 & '98 cylinders, so that should help.

http://www.partzilla.com/parts/detail/yamaha/YP-4SR-11631-00-B0.html

Good luck, and keep us updated with what you find. ?