I found some threads on this topic and wanted to get some more info. Is a needle change the way to go with this setup or have you been able to keep the stock needle? Just fwi this is mikuni on an 03 cr 250. The part numbers are 3tc-14141-s8-00 (nozzle main) (bike bandit p/n 39104-001)Also can anyone compare this to the JD jetting kit?
Thanks
I go 1 size richer on the needle when using the S8. I've done some back to back testing between the S8 and S9. The 2 nozzles are very close when changing the needle, but the S8 with a richer needle runs a bit cleaner. It's pretty marginal, but worth the cost IMO.