2001 KX 250 problems

My 2001 KX 250 is having intermittent spark and acting weird at the powerband. Right before it hits the powerband, it seems to lose power and rev out. I just got it on a trade and it ran perfectly when we were trading, I guess I have bad timing. On the way to the first trail I would have ever taken it on it cut out on me and wouldn't start back. Currently we have all the electricals regarding the Sparkplug out, as the sparkplug had 1 hour on it and I put on a new one and it didn't help. Anyone heard of maybe a bad coil affecting the powerband?

worked on it some more, the starting issue was a loose connection. fixed that all up. just having problems with the powerband now... it feels like its signing off at a certain rpm in each gear, took it down the road and could barely gas it at all. Opened the power valve on the side on the motor, seems to be working fine there. Cleaned out some gunk. If any better not much at all.

Edited by Chrone247

Cleaned the carb, still being stupid. Emptied the tank, gonna try to remix the gas incase its just loading.

Jetting issue maybe.  If you wrap the throttle back and it lugs then hits high RPM's it would be too rich.  If your wrap the throttle and it hits good then bogs then too lean.  Hopefully you are running it too lean and that would be a simple fix.

I think it would be too lean. Im new to 2 strokes and this is my first dirtbike, haven't even hit a trail yet. Used to quads. It runs good then bogs but I think I mixed the gas too rich. I went for 32:1 but I believe I may have messed up due to lots of spooge in the exhaust (it even dripped some) and a lot of smoke. Drained the gas to remix, letting my dad mix this time. He rode when he was younger. How would you recommend fixing it? Isnt there a fuel-air mixture screw or would I need to remove the jets from the carb and change them?

I think it would be too lean. Im new to 2 strokes and this is my first dirtbike, haven't even hit a trail yet. Used to quads. It runs good then bogs but I think I mixed the gas too rich. I went for 32:1 but I believe I may have messed up due to lots of spooge in the exhaust (it even dripped some) and a lot of smoke. Drained the gas to remix, letting my dad mix this time. He rode when he was younger. How would you recommend fixing it? Isnt there a fuel-air mixture screw or would I need to remove the jets from the carb and change them?

It's a jetting issue. Not a oil to gas mix ratio problem.

 

And yes that would entail pulling the carb and changing your jets. But only after you figure out if you're running lean or rich. Have a look around on the net for some guides, some good ones out there.

Okay, thank you. I'll look around and see what I can do.

If the bike is stock, then stock jetting is fine. Maybe one leaner on the pilot.

 

Before you try tuning anything, make sure you install a new plug first.

Yeah I did a new plug. I'm going to prociruit recommendations for my full platinum pipe. I'll take apart the carb again today and see what's in it

Whew, found the problem. Main jet is a 152, stock is 160 and pro circuit recommends 158. Ordering a new main today from rocky. I'll update if it fixes it

Fixed it! All it needed was a 158 main.

Well, it ran fine for about 5 hours then cut off with the new main. gave up and took it to a shop, the previous owner had forced the wrong clutch basket in and forgot washers, the clutch basket was apparently having contact with the crank, and I need new crank seals, bearings, crank, and clutch basket.

Well, it ran fine for about 5 hours then cut off with the new main. gave up and took it to a shop, the previous owner had forced the wrong clutch basket in and forgot washers, the clutch basket was apparently having contact with the crank, and I need new crank seals, bearings, crank, and clutch basket.

Some people shouldn't ever pick up a wrench......the previous owner of your bike is a case in point, good luck with getting it on the dirt again.

He claimed to be a certified mechanic too. Thank you, hopefully I'll be out this weekend

I'm going to to give you guys a little secret if you use a new plug you will not know how rich or lean your bike is running use a used plug not an old one but a used one a used one will show up a lot faster and easiser and you will know which way to go with your jetting

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