87 250x engine info

[dman66]

new guy here. what stroke is this engine- 2 or 4? Do I mix oil in with gas? I acquired an old fixer upper, currently rebuilding the rear swing arm. Fixing brakes is next, then fix leaks on engine, or find a used 300ex engine.

[IcutMetl]

The 250x and 300ex are both 4-strokes. No oil/gas mixing. Run a quality 10w40 ATV-only oil in the crank-case with a clean filter and you're set. Pretty bullet-proof, reliable motors that are very much alike; the 300ex is actually a 282cc I believe, and has electric start while the 250x is a kicker. You should be able to find just about any part you want out there on ebay for it. I've heard that you can build a fair amount of power out of one with mild engine work.

Check out another forum on here "other sport quads under 350cc"- you might find some info there as well. Also, don't be afraid of using the search function. I've spent hours finding good info for my 250r on here.

Good luck & have fun with it!

[dman66]

Thanks for the info. My engine smokes, so I'm wondering if the previous owner mixed the gas or it's actually the engine needing rebuild. I'll dump the tank today, and put in fresh gas.