If you’re looking at getting an older 250f, and possibly a Kawasaki or Suzuki, then you should probably consider some of this info. When these companies made their 250f, it was more like a Kawazuki 250f, because Kawasaki and Suzuki had partnered up. So most of the parts on these bikes are interchangeable. This was their first year making the 250f, so just by that you should be a little worried.
As some might expect, these bikes were not the greatest reliability-wise in 2004. Although they were fast bikes, they had an overheating problem caused by a bad/weak water-pump. Another defect these bikes had was in the valve-train that caused the valves to burn-up more quickly. These problems can get bad and scared me away from buying one of these bikes. This is not to say that these bikes do not perform. They have plenty of power, and if you really want to get one then I suggest you get a newer style complete cylinder head and get and aftermarket water-pump and impeller to fix the overheating problem. If you do that then the bike should be fine, but by the time you spend all that money on parts you could have bought a newer bike more than likely. Good luck, and remember that no matter what you ride, have fun and stay safe! Thanks
What do you get with a bin full of dirt bike parts and an eager mechanic looking for excitement and satisfaction? A great project rebuild! If you are a dirt bike grease monkey like me who not only likes riding their bikes but sometimes working on them too then this is for you. I enjoy project rebuilds and love the oh-so greatly anticipated finished product even more. Ever since I got into dirt biking I have gained more knowledge about how they work and how they are put together. So after doing many rebuilds myself I thought that I would share the experience with you fellow riders.
I bought this 2003 Yamaha YZ250F in pieces as a project bike thinking that I would have some fun and get some more experience putting another bike together over the next month after I bought it. It came needing a complete new top-end at the least. I managed to get one and put the engine together in a reasonable amount of time. I then slapped the engine in the frame and started the process of puzzling the rest of the bike back together; this is where the fun started. It only took a few short minutes of bolting parts on to find that there was stuff missing. The more I put together the more parts I found that were missing or broken, and they were not all at the same time. So one-by-one I had to buy parts that I needed to piece this thing back to its somewhat original form. These parts consisted of, including engine parts, clutch plates, radiator shrouds, timing chain, timing chain slider, a different piston, head pipe, a couple crank bearings, engine/frame mounts, air filter, cylinder head breather hose, chain, gas tank, clutch perch assembly, a shift lever, and maybe a couple other miscellaneous things. Figuring out that we had to find and buy these parts got a little frustrating because we were told that the bike was complete and that it just needed a new top end.
Well, after weeks of picking at my wallet this bike has finally been put together and is running. It just needs a couple things put on to be ride able. So once I get those together I’ll take it out for a spin. The process was long and somewhat miserable, but I think I learned a lesson and gained more experience and knowledge about these modern four strokes that basically took over the world. In the spring, if not sooner, I will be putting on some new bling to make this baby look new, but as of right now it’s a clean bike that runs. Thanks for checking out this rebuild process, and make sure to check back in the near future for another bike rebuild! (If you liked this article make sure to check out my other rebuild, “I Rebuilt My YZ125 In A Closet!?”
P.S. I might update this article with some pictures and/or video once I get this bike looking good. Questions and comments are welcome.
When I got the bike (as you can see, I had my work cut out for me):
Pic of the damaged cylinder head:
After I cleaned it up and the engine was together in the bike:
Put the wheel and handlebars on:
The bike put together (added sub frame, carb, electronics, old plastics, seat, exhaust, cables, etc.):