Need jetting help

need some advice... heres what I got;

2003 s with base gasket, airbox mod, end cap mod, dyno jet kit.

My bike will not run right with the clip on the 4th, a 140 main and a 25 pilot. It does pull very hard, but cruisin at 60 or so, it hesitates like its running out of fuel. I tried the 5th position and it seemed to run good at cruisin speed, but got a little flat under accelearation. ( I do not have the spacer washer for 4.5)

I tried it back on the 4th with a 142.5 main, but the thing bucked during hard acceleration up around 50 and then died a couple times like it ran out of gas.

I'm almost thinking of going back to the stock needle and 150 main and 27.5 pilot.

Any suggestions???

Seems like the 5th needle and 140 main combo would be almost the same as a 4th needle and a 142.5 main.


i think you have another issue.malfunctioning fuel valve,side stand switch,something of that nature.

I agree you have another issue beyond jetting. A vac leak, or fuel valve would be where I would start. You never know on the S they could be the same problem :naughty:

Ok thanks.

Question, is the 4th clip with a 142.5 main the same as a 5th clip with a 140?

(DJ kit)

no.the main jet and needle do 2 different things.

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