ok so i just got given this real old klx 250 from 1982. heres a pic

It hadnt been ran for about 10 years but when it was used years ago it ran fine. When i got it i cleaned everything and took apart the carb and cleaned that thouroulgy. Now it runs but ticks over very strangley. It either ticks over really slow and u need to keep revving it otherwise it dies or it speeds up for no reason by itself and sounds really bad. ive messed with the mixture screw ting and the carb settings but i cant solve theproblem. also when riding if you open the throttle up it lacks power, you have to back off then build up the revs slowly to get some decent power out of it. any help would be appriciated or any advice of how to get it running right. Im new to motorbikes so help would be greatly appreciated. thanks alot.

 

Wow, thats a sweet score. Reminds me a lot of the '87 tt225 I picked up for next to nothing!

 

the one thing you might want to check is the Carb intake boot I would bet it leaking just start it and spray some carb cleaner in the area if the idle goes up you have leaks.....I would guess it might also need a good tune up valves and cam chain for sure that would be a good start and do a compression check first ......Good Luck

 

you also might want to check and see if theres any world-warI spirits haunting the engine. you might want to invest in a witchdoctor[8D]

 

ok, been out on it today and after a while the engine calmed down, however more problems occured. The bike wouldnt start by using the kickstart and got to the point where it wouldnt turn will my full weight on it (too much compression??) could this be because the exaust isnt attached to the engine properly and air is escaping or something? As the day went on though the kickstart was turning but felt like it was slipping inside the engine, it was really easy to turn and no compression. Anyone know how to solve this as bumpstarting it evertime is annoying. sorry if im not making sense, i dont know much about bikes and am only 15.

 

That's a very interesting bike. It looks like it's actually a conglomeration of several bikes. The engine definitely looks like the '79-'80 KLX250, as does the rear swingarm. The forks don't look right, though, and the disk brake up front is definitely not off the KLX. Rear shocks look better than stock, maybe aftermarket or something? Kick starter isn't stock. Very interesting. Looks like the "mighty mongrel" of dirt bikes.

So you can still bump start it but the starter isn't doing you any good? First it was hung up and now it isn't doing anything? It sounds like it bound up and then possibly broke. You'll need to pull the right side case to find out. This is an easy bike to work on, I have an '80 (I don't think they made a KLX250 after '80, but I could be wrong.) eBay is a great place to get parts. I rebuilt the one I have and spent over $700 on it. Dumb move. It's not worth $500. I have an extra shop manual I was going to put back on E-Bay. I'll let you know when I do that and you can pick it up if you want it. I may end up selling my '80 on eBay or parting it out. It's not worth much, but it runs good and will lug someone around the hills (they run like a tractor.)

Your initial engine performance problem definitely sounds like a vacuum leak. The other place to check is the enrichment circuit (choke.)

 

ok. cheers coveor. the previous owner used to race it and stuff and put the front end of an old yamaha on for better perormance and other things including a supertrap exaust. How would i go about sorting a vaccum leak? is it from the engine or carb or where? also i think something is missing from the engine, above where the exaust goes into the engine there is a hole with threads on it and an rod in the middle which spins when the engine runs. a bit of oil leaks out of this hole aswell. cheers guys

 

Cool bike! I'm a sucker for cheap old neglected bikes too!

Along with checking for vacuum leaks and all the basic tune up stuff like new spark plug, clean air filter, valve clearance and timing, you'll want to make sure the bike has fresh gas and a clean fuel system with no water or particles in it. Take the gas tank off and clean it out, and put a little fuel filter in line (if it doesn't already have one). If you find any type of crud at the bottom of the tank, you'll probably need to pull your carb again and make sure it's still clean inside.

Good luck! Keep us updated on your progress! [sm=interesting.gif]

 

The vacuum leak could be in the carb or in the boot between the carb and cylinder head (intake manifold.) The earlier suggestion of sprayingstarting fluid around the carb and intake manifold is the traditional way to find these leaks. If it speeds up and/or smooths out look closer in that area. Of course be careful of spraying where there may be an exposed spark. We don't want you to lose your eyebrows!

If you're talking about the "hole" just above the exhaust manifold and beside/below the exhaust valve adjustment cap, my engine has a screw-in plug there. That leads to the camshaft, so don't let any gritget in there. I wonder if that's a mechanical tachometer drive? I don't see a reference to it in the manual.

 

Looks to have the Supertrapp pipe, and you mentioned that you couldn't kick the bike over as in too much compression, it may be getting too much fuel and hydro locking. Make sure the carb isn't stuck giving the motor too much fuel. It doesn't take too much to lock it up. Oh and welcome to the site man.