High altitude jetting

I'm getting ready for some long distance touring. Leaving WI (alt. 500-700') Going to West Fargo, ND, Sturgis, SD then south to Las Vegas NM. Plan to stay in NM for a month or two. Las Vegas is at 6500' I think. The route will take me through the mountains. The bike is jetted 15 pilots, 105 mains, 5CN7 needles clipped on the third groove, and is running great. Anyone have an idea what changes need to be made for the upper altitudes I will encounter?

Wikipedia has the altitude in Vegas listed as 2100 ft. Apparently, you can get up to 4000' in the surrounding suburbs. If anything you will need to be a little leaner (smaller jet #'s) at higher altitude, but it shouldn't affect you too much at just 2100 ft. I wouldn't think that a temporary trip through the mountains would necessitate a jetting change, but you will be a little rich at higher altitudes. You may not receive optimum performance, but that will be a temporary condition. I guess it wouldn't hurt to carry one size smaller main and pilot just in case. It's not like 8 jets are going to weigh you down.

Good luck with the trip, and do take some pictures for us.

Ive ridden my GPZ750 over Beartooth Pass in Mt @ 10,500 ft all the way down to Death Valley with stock jetting with no problems, I wouldnt worry about it

Agreed, I wouldnt worry about it. A slight adjustment to the mixture screws maybe, but otherwise, you will just feel slight changes in performance throughout the throttle range/power delivery - no biggie.

Good luck.

testarossa wrote: Wikipedia has the altitude in Vegas listed as 2100 ft.

Good luck with the trip, and do take some pictures for us.

You're thinking of the OTHER Las Vegas. I'm heading to LV, New Mexico. It's a town of about 15,000 population 65 mi. east of Santa Fe. It is at 6425' alt.

My mains are 1 notch larger than stock 105 vs 102.5. I'll take the 102.5's along. I'm thinking maybe raise the clip on the needles one notch and turn in the mixture screws 1/4 turn for the ride in the mountains. Wadya think?

TeK9iNe wrote: Agreed, I wouldnt worry about it. A slight adjustment to the mixture screws maybe, but otherwise, you will just feel slight changes in performance throughout the throttle range/power delivery - no biggie.

Good luck.

I like that attitude, No worry, mate. I won't. I will take pictures though and post some here. I'll be leaving about Aug 4 for the first leg to West Fargo, NoDak.

TomW wrote: You're thinking of the OTHER Las Vegas. I'm heading to LV, New Mexico. It's a town of about 15,000 population 65 mi. east of Santa Fe. It is at 6425' alt.

My mains are 1 notch larger than stock 105 vs 102.5. I'll take the 102.5's along. I'm thinking maybe raise the clip on the needles one notch and turn in the mixture screws 1/4 turn for the ride in the mountains. Wadya think?

I'm an idiot. That's what I think.

Seriously, I think that your plan seems reasonable. Just be prepared to deal with any potential issues. The fact that you are even asking about it before tells me that you can handle the issue. BTW 1/4 turn can make a huge difference in AFR at idle. I have seen this on my wideband 02 sensor. Just adjust as needed to get your idle right. Carry the spare jets for the remote possibility that you start fouling plugs at altitude.