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Carb adjustment for hi altitude

Old Jan 16, 2006 | 02:08 PM
  #1  
glenreaper's Avatar
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Default Carb adjustment for hi altitude

Hello, Im new to this so please bear with me!

I have a '04 Raptor 660. I have recently moved to the mountains and I ride between 5000 and 7500 feet in altitude. My top end is OK, but at lower revs, the motor really sputters. My buddy suggested a Eldebrock 2 into 1 carb. Any feed back or other solutions?
 
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Old Jan 16, 2006 | 02:42 PM
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hondabuster's Avatar
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Default Carb adjustment for hi altitude

It might be as simple a fix, as turning the mixture screws in 1/4 turn.
As you go up in altitude, the air is thinner, and the mixtures go way rich. Because theres less air...the carb needs to give less gas.
Theres two routes you can go...let in more air(which isnt that easy to control, such as cutting openings in the lid, or removing the lid), or let in less gas (using the mixture screw and pilot jet for the low throttle positions, which is easy to control)
Theres no reason the setup you have cant be made to work, no need to spend big bucks.
Heres a real good article on do it yourself jetting. It has a list of symptoms of lean and rich, which helps figure out which way you need to go with the jetting.
article here
Welcome to the forums
 
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Old Jan 16, 2006 | 03:06 PM
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glenreaper's Avatar
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Default Carb adjustment for hi altitude

Thnks, Ill try it. Just for my info, how do I keep the carbs in sync? How many turns out should the adjustment screws be from the top?

Glenreaper
 
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Old Jan 16, 2006 | 05:35 PM
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fastquad02blaster's Avatar
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Default Carb adjustment for hi altitude

If the carbs are similar to the one on my blaster, In the dynojet instructions, it says that all you have to do is move the e-clip up one notch on the needle. I'd say that you'll probably have to fine tune the idle mixture and idle speed, but that's what it says for a blaster.
 
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