Join Date: Oct 2007
Location: Redwood City, CA
Rep Power: 1
89 TW200 won't idle
I need help.
89 TW200 yamaha trailway. Barn fresh with 700 miles on it.
So far: new petcock, cleaned gas tank, new air filter, new spark plug. Fresh oil.
Carb: cleaned, roughly 5 times, new needle valve & seat, float level verified, cleaned emulsion tube & new o-ring, cleared jets, air fuel mix screw out 2.5 from seat. Honestly, I would eat off this carb. It's that clean.
I'm stuck. Starts/runs on full choke. Warms up, runs clean, less and less choke... Push the choke in completely.... dies. Hold throttle open a touch, no choke, runs fine. WILL NOT IDLE on it's own. The obvious answer is to crank the idle screw up but that ends up being quite a bit. Plus, I like to have things done right.
My thought is pilot jet or the passage it follows. Correct me if i'm wrong. The choke, main jet (for throttle), and pilot jet (for idle), all draw gas separately from the carb bowl. Right? Can pilot jets wear out? I'm sure it's clean. I just checked.
I need a few of you gurus to help. I need a full list of things to check, start to finish. It's getting spark cause it runs on choke. No misfires or smoke or backfire. But I'm at a standstill. I don't even know what the next step is.