need reccomendations re-jetting 650R for altitude

I just drove down to southern CA and picked-up this 650R on Friday. When I pulled it out of the garage today, it started pissing gas out of the overflow hose and I had a hell of a time starting it. It was still pouring out gas after I warmed it up and rode it for a few minutes, so I pulled the carb out and took it apart to see if it was gummed up. There was a little bit of junk in the float valve, so I'm thinking everything will be fine once I get it back together. But I would like to re-jet this thing for the altitude here in Bend while I have it apart. The elevation here is about 3700ft and I'd prefer to jet it for best performance around this altitude and lower. Thanks in advance for any helpful input.

Engine info:


Hot Cams - Stage 1

Pro Circuit T4 head pipes and silencer

DT1 air filter

PO told me it has an oversized intake boot on it?

Current jetting:

Main Jet: 175

Slow Jet: 65S

Jet Needle: B53E (C-clip is in the 3rd groove - middle of five grooves)

Pilot Screw: 1 1/2 turns out

You can look at jetting specs on-line. Just google the pig pen xr650. This will probably be what you are looking for. As for your overflow problem... More than likely you had something stuck in your needle and seat that your floats actuate. If you haven't already, clean both with carb cleaner and you shouldn't have any troubles.

Thanks. I've seen those jetting charts, but the +2 -1 stuff wasn't making a whole lot of sense. I don't know if I have the stock needle and that chart doesn't mention how cams affect jetting. My best guess is that I might be OK with the main jet and the needle settings, but I should change the slow jet from a 65S to a 68S. Does that sound about right? Maybe jump up to a 178 main jet?

It also looks like the recommended jetting for different termperatures varies a quite a bit. Right now it's only about 30-degrees here, but in the summer time it ranges from mid-80's to the low 100's. If I jet the bike for this cold weather, how well is it going to run in the summertime?

The plus and minus symbols mean size of jets, like if it has a plus one, that means one size larger than what is otherwise recommended on the chart.

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