broken air screws

[Slickster25]

Hey guys, I've read a lot of blogs about carb problems. I had all the classic symptoms, poor starting, hanging up at 3~4k rpms, running rich etc... After cleaning, and boiling and cleaning... with no luck. What I found, was the tips of the air screws were broken and stuck in the carb body. If you unscrew the air screw(s), and can't see light thru the bottom, chances are the tip of the screw is snapped off and stuck in the carb body. I was able to push the stuck tips out with a dental pick, and machined the broken air screws back to a point, used springs with fewer coils, and FIXED! Replacement screws for my 1977 XS400 were $45 a pair, so I re-machined the OEM ones. Carb Blues? Check your air screws!
Jim

 

[Sesty]

did you check mikes or ebay?

that seems expensive for new screws

 

[xschris]

Mikes don't carry those type. $45 a pair is what yamaha gets for them.

 

[Sesty]

thats rough...