Hi. I want to know the stock # of the main jet of a stock LT500 Carb. Is it #350 or #420?. The carb ID Number is 43B10. How this #'s work, larger numbers mean larger jet bore? Which # can be a start jet for carb tuning? Thanx!!

Juan C Curet

 

Try this web page. The box on the right has some jetting info.

http://www.offroadhaven.com/ltquad_details.htm

 

In 87 it was the 420 main I think the pilot was 35. In 1988-90 it is the 350 main and the pilot is 22.5. I think your carb number is off a 88+ You will have to figure that out. The larger the number means the bigger the jet. You wont have to go much larger or smaller unless you`ve done other mods.