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Should I tackle this XR 400 Carb myself?

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Hey, everyone.

This '02 XR 400 I just bought is not only hard to start when cold but simply will not idle wihout the choke on... Even after it's warmed up. I suspect that these are different problems, and I'm more concerned about the second one, as it keeps me from riding the bike.

I'm at 7000 feet, and temps range from 20- 70 deg. F. I've messed with the little screw (I think it's the pilot screw) in the front bottom of the carb and messed with the idle adjustment. I've also taken off the bottom bulb and cleaned it out (it wasn't dirty), took the jets out that are accessible from the bottom abnd cleaned those and I blew some carb cleaner up into the little holes. The guy who had it before me said it had been sitting for at least a couple of months with no stabilizer in the gas... It has 700 miles on it.

So, my questions are:

1. Could this be a jetting problem?

2. Are there other possibilities?

3. Should I remove the carb and take it all apart and clean it out?

4. Should I do this myself (I have all the tools and a Haynes)?

My friend says I should just have a beer and tear into it but I'm a bit intimidated...

Thanks. -drk

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Have you had it back together yet after the initial cleaning and tried to start it?

Did you happen to notice what the jet sizes were while you had them out?

Has the bike had any intake/exhaust mods done to it, like having the snorkle removed or UNI filter or modded stock or aftermarket exhaust? Or is it completely stock? All this needs to be known before asking about whether it can be a jetting issue.

The stock carb is pretty simple. Don't let it intimidate you.

If you don't drain the float bowl of old gas when a bike has been sitting for that long, it's going to be tough getting it to start, if at all. Dump the old gas and get fresh before trying to start i again.

Now's a good time to change the spark plug so you'll know it's condition and rule it out as a problem.

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Thanks for the reply. I cleaned the plug and the bottom bulb, and yes, I've had it running since then. I runs fine at higher rpm's and under load... it's just a bitch to start when cold and it won't idle w/o the choke on.

I did not check the size of the jets, but I assume they're stock...

thanks. drk

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Hi,

Did you fix the problem as mine sounds identical, Bike was running fine but gthen wouldn't start. Drained carb bowl, started second kick, would not run with out choke on. Revs fine with choke on but splutters when choke off.

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plugged pilot jet.

Thanks, thats what I thought, I will pull it out and clean at some stage.

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