Baseline jetting for a modded 650r

I'm just about done with my 650r rebuild and know a lot of you have the same/similar configurations:

11:1 piston

hotcam stage 1

ss valves

all new OEM valvetrain (aside from valves)

competition valve job

uni filter

opened up the side cover

removed the smog crap

white bros e series silencer (stock header and mid pipe)

I'd love to get the Edelbrock carb but my budget is already stretched so in the meantime, my question to you all is about baseline jetting for the stock carb. I'll be mainly riding in the 0-3000 ft level with the majority of the time spent under 1000 ft.

From researching it looks like I should start out with a 70 pilot, 180 main, stock needle with clip in 4th position. Does this sound about right? I do have the 68s pilot, competion needle and some other jets on order as well.



you seem to have answered your own question. Correctly. Now go pop some wheelies. :devil:

Excellent, thanks! Just wanted to make sure I was on the right track.



The "competition" needle will make a noticeable performance increase in your application. How big is the opening in your side panel?

70 pilot, 180 main, stock needle with clip in 4th position....that is where I would start. :devil:

Ram: I have ten 1 inch holes drilled in the side panel using uni pop-in vents.

Took the bike for its first ride yesterday, what a blast! Wheelies on command :devil:

The only issue I had with the jetting setup is that it would only run good at half choke, otherwise it would bog and die at anything over 1/4 throttle. Had a small amount of popping on decel as well with some residue on the exhaust baffles. I'm going to move the clip to the 3rd position and see where that gets me...

If it runs good with the choke on it needs more fuel. Stay with the 70s pilot and richen up the fuel screw. If you need to richen it a bit more try covering one side panel hole at a time.

Hmmm, I am currently using a 70 pilot, sounds like I need the 70s instead. Any adjustment I made to the fuel screwn yesterday didn't help... I thought soot on the exhaust was an indication that the bike was running too rich, or is that probably just due to the fact I was running with it at 1/2 choke?


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