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Just Moved From Sea Level to 6000ft - Need Advice

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Just Moved From Sea Level to 6000ft - Need Advice

PostAuthor: MadAdventures » Mon Mar 20, 2017 7:10 pm

Hello everyone!

This is my first post on this forum, so bare with me!
I just moved from sea level, Louisiana (where I purchased my bike), to roughly 6000ft in Colorado Springs. I road it here with no problem, except whenever I got to New Mexico, it started having a significant power loss, especially in 5th gear around 4k rpms. I've read that I may need to adjust my mixture, but have never done that before, and don't know where the mixture screw is, or how I should adjust it. Does anyone have any advice? I'm planning to go in a mountain ride here in the next few days, so I can imagine that it'll be worse at higher altitude.

Thanks in advance for the tips! :usa:

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Re: Just Moved From Sea Level to 6000ft - Need Advice

PostAuthor: turbodog » Mon Mar 20, 2017 7:57 pm

Hi and welcome. Unfortunately, you need to adjust your high speed mixture, not the idle (well, maybe the idle also). The main jet has to be changed, and requires removal of the carbs (not too bad once you've done it several times... but that first time will be a frustrating experience), removal of the float bowl, and replacement of the main jets with leaner jets. Less air at 6000 ft = less fuel to keep the mixture right. Less power is an unavoidable by-product. Look at your plugs and verify they are sooty before deciding your path. It is not something to tackle a day or 2 before a major ride. You will have to order the jets online. Is the bike stock (particularly the exhaust)?
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Re: Just Moved From Sea Level to 6000ft - Need Advice

PostAuthor: MadAdventures » Mon Mar 20, 2017 10:52 pm

Damn. I feared that since I've never messed with carbs before. What jets do you recommend? Everything is stock, including the exhaust.

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Re: Just Moved From Sea Level to 6000ft - Need Advice

PostAuthor: turbodog » Tue Mar 21, 2017 12:51 pm

The change in jet is proportional to the change in air density. For example, if your current jetting (122.5) is correct at sea level and 80 degree temps, then the jet needed for 6000 feet and 60 degree riding is 118. Here is a link to a site with a very useful chart:
http://www.horizonsunlimited.com/tech/carbjet

You might try fitting a less restrictive air filter (K&N, etc) to see if that improves airflow enough to get you through your upcoming ride.
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