1983 XR100 Redline Idle on Full Choke


I've been working on my '83 XR100 trying to get it running for my nephew to learn to ride. Damn if this thing doesn't want to run...:thumbsup:

Anyway, here's the symptoms: Bike will only start on full choke but then revs to the moon. If I reduce choke to 1/2 or off, it immediately dies. Also, if any throttle is added (even though it's revving high), it immediately dies. I've turned out the throttle stop all the way with no effect to idle.

Here's what I've done: Completely disassembled/cleaned the carb, replaced all gaskets, o-rings, and seals on the carb and manifold.

Appreciate (very, very much) the help, the weather is getting nice and I'm getting the spring itch to ride!



1)year/make/model: 1983 Honda XR100

2)conditions (elevation, temp, humidity if extreme, type of riding): Michigan, flat, barely 500ft max above sea level.

3)modifications (pipe, air box, motor): 100% stock

is the slide in backward?

I don't think so. The short slot with a ramp in it is on the same side as the idle set screw, the long open slot is on the opposite side, I believe there is a small pin in the bore that the slot slips around.

The odd thing is while it's revving high, any additional throttle (more air) just kills it. Same if I go to 1/2 or open choke, dies instantly.

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