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High Altitude Carb Adjustment

838 Views 16 Replies 7 Participants Last post by  Ridgway81432
I have two 04 & 06, 660's and live in North Alabama, I'm taking them to Colorado in July for 3 weeks of riding, has anyone had any luck with Thunder products "Dial a Jet" that leans/rich the carburetor? A lot of people change the jets to accommodate for altitude, we will be riding 6000 up to 12000 ft. Thank you in advance.
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One of your better sources of information for high altitude riding with a 660 will come from @Ridgway81432. I seem to recall reading posts from him that he doesn't change the jets on his 660 but more so, drilled holes in the top lid of his airbox to help increase the flow of air... he can confirm on his recommendations for high altitude riding on a 660. Certainly one way to address being down on power is to magnify your low end torque by way of CVT mods and Ridgway is well versed in that as well. I've never had a 660 but CVT mods are how I've addressed being down on power here in CO on my 700. 700 being fuel injected.

One other item to point out that many don't think about... make sure and check/adjust your tire pressure when you arrive. It will have increased by quite a bit. But conversely and probably more importantly, make sure you are aware that your tire pressure will decline as you make your way home where you could end up with very low psi in the tires. If securing your ATV will be affected by tire psi lowering, just make sure and check tire psi, add air during your travels when needed. Not saying you need to stop every hour to check but maybe check on your first/second fuel up during your return trip.
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yes we even lower psi in mountains of Tennessee as it grips better
Maybe I'm misunderstanding your response so adding a little more info which I should of put in my original response. It's not just about lower psi in tires for better grip on technical terrain. If I remember the numbers correctly, I've ridden with some that travelled out here who came from low elevation areas, say 1000 feet above sea level. When they arrived where we were base camping, roughly 9500 feet, their tire psi was up to around 15 psi or so. It was way above what they set the pressure to before leaving home and they were very surprised when I told them to check tire psi. So they lowered psi back to their normal riding pressure. But on the way home, they stopped to air up their ATV tires some to make sure their loading straps continued to hold tight.

Since the 660 is a bit older now, not as many on here discussing the 660 as regular as the 700 is discussed. Having said that, I can't recall ever seeing the mention of someone using a Dial-A-Jet but certainly doesn't hurt to ask about it.
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