ruckus running rich when cold an wont idle.

General / Honda Ruckus
#1

This is a new problem. i didnt ride it for maybe 3ish weeks and the next time i went to, it would not idle. When the engine gets hot, it idles and runs perfectly. When its cold theres too much fuel and rpms drop so low it dies.

I thought maybe it was the bystarter, but the bystarter is receiving a steady 12v power and i just replaced it and it did not fix the issue.

i dint change anything that would have changed the air fuel ratio. obviously this is some sort of carburetor clog issue. However i was wondering if anyone could tell me exactly where i should be looking for a clog in the carb?

#2

Is it really hard to start when cold? I had a similar situation years ago, took the carb completely apart, checked the jets, ran Gumout through every orifice, swapped bystarters, no change. Turned out to be an intake valve issue. They get tighter over time, and eventually reach a point where they won’t start and idle when cold. I checked clearances and sure enough the intake valve had zero clearance. I did the math and replaced the shim with a smaller one to get proper clearance. Solved the problem completely. I did a write-up about it on OG TR, seems to be a fairly common issue.