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Hey guys any help is much appreciated.

I was riding my 98 kdx 220r last week and I was cruising at a medium rev when suddenly the engine died. I started it back up and revved it up a little but it dies whenever I let off the gas to let it idle.

After taking the bike home, I cleaned the air filter, cleaned a few carbon deposits out of the exhaust, checked the spark plug and wires leading into the spark plug, everything looked fine. After reinstalling a clean air filter I started it back up only to have the same problem: it starts fine but unless you keep giving it a fair amount of throttle it dies and will not idle.

Can anyone offer any ideas about what I should look at next?? The bike has given me tons of good riding up until now and it happened pretty suddenly. I am fairly new to owning a dirt bike so I need some help from the experienced 2-stroke riders out there!!!

THANKS!!

The carb is where you need to look.....

carb plugged up somewhere

Not that it needs to be said again, but you have a blockage in your carb.

third time is the charm?

Probably the pilot jet too...

Thanks for the quick replies everyone, I'll check it out!

Indawoods wrote:Probably the pilot jet too...

My 200 has done the exact same thing. Was a clogged pilot jet.
Took it out and blew it out with carb cleaner until I could see a ROUND hole through it. Put it back in and the bike ran fine.

I always run a guitar string through it... cleans them up real quick. You would be suprised the amount of junk that comes out of them. Then there is the little side holes that you gotta make sure are clear....

Thanks for the quick replies everyone, I'll check it out!

I keep a couple guitar strings in my toolbox these days. Damn ethanol..... :|

Surely it's the carb, but hope it's not the piston. This would be a good time to remind you to change the factory 220 piston ASAP if you haven't already done so.

Update:

I took the carb apart and completely cleaned it. It didn't look too bad, but those jets are so small I can see how even a little residue would change things. I also took the reeds out and they looked great.

Peering into the cylinder from where the reed box is located I could see one side of the piston. It looked fairly new and I did not see any obvious signs of blow-by or cracking. The guy I bought the bike from told me he had put in a new piston a few months before I bought it. I'm not sure if I completely trust him, but I could not see any obvious signs of the piston being worn or cracked (although I had a very limited view from the reed box). I decided not to take the whole engine out and inspect the top end.

Next, I installed a new spark plug, put the carb back together and put everything back together on the bike.

With everything back in place, I started it up and again, the bike will run, but won't idle unless I give it a little throttle (probably less than 1/8 throttle). However, this time (after cleaning the carb) it does seem to require less throttle to keep it running than it did before I cleaned the carb (maybe needed 1/8-1/4 throttle).

Anyone have any ideas? Could it just be an issue with tuning the carb? The idle screw is about .75 turns from being all the way in. The air screw is about 1.125 turns from being all the way in. I ride in Montana at about 5000-6000 ft elevation in temperatures anywhere from 60-80 degrees F, with a 1:40 gas mixture.

I have read a tuning guide here: http://users.conwaycorp.net/virtus/page ... etting.htm

But, does anyone else have any advice or resources they could point me towards?

THANKS!!!!

Where are you located?

Bozeman, Montana