Need some help diagnosing - here's the issue:
(bianchimatic with a 14:9sha)
It'll start and run strong for about 2 miles - can reach 25mph wot
Idles ok at stops but at about the 2 mile mark it'll start to struggle at stops, and will stall if I have to stop around 3 miles.
If I let it sit for 5 minutes , it'll start back up and run again...only a shorter distance if I have to stop.
However if I can stay above 10mph it'll run strong. Only problem seems to be when I come to a stop.
Initially I noticed that the fuel line was empty when this happened so I thought vapor lock. I put different gas cap on, even ran without a cap for a bit, then tried a new fuel filter. Same issues. Then I took out the filter altogether - same problem (except without the filter I noticed the fuel line wasn't empty).
for what its worth, the spark plug was new in the fall and hasn't had many miles on it yet. still, could be something...?
I'm stumped