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Planned a trip down to Monterey and didn't think about the change in altitude if it will lean out my bike to much. Info on the bike has big tube header, slip on, k&n filter.
 

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Is your bike running just Lil fat or already on the lean side? If you stay very long id be jetting it. But if your not staying long and no fast long riding and going back wouldn't worry about it. May pop some and sound different lol
Kind of a pain to just swap jets.... be on safe side id go up jet size.
 

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If your going down in altutude wouldn't that richen the bike?
No sir, they are right the lower the altitude the leaner you will get. As you increase altitude, the density of the air decreases. There is less oxygen available and the fuel/air ratio becomes rich. So just the opposite which would mean getting leaner.
Now as for the messing with the carbs because of altitude put new plugs in right when you get there after some riding check them and see how its running and it will tell you if you should do anything to the carbs or not.
 

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2000 ft. isn't that much. In my opinion it's not going to be as significant of a change to be worth while changing the jets. It's not going to run quite as good as it is now of course, but it's not going to kill the engine. Make sure you run good fuel.
 

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Here is a tip a guidelines for good tuneing when changeing air temp and elevation.
And yes you get leaner needles or larger jetting when dropping altitude.
When I go Colorado I go down in jet size and fatter needle I'm at 700ft and there is 2200-2800 where we go.
HERE YA GO YOUR WELCOME
FAQ REJETTING FOR ELEVATION AND TEMPERATURE CHANGE

You can also change plug temp by getting hotter or colder plug to make up for changes.
 

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2000 ft. isn't that much. In my opinion it's not going to be as significant of a change to be worth while changing the jets. It's not going to run quite as good as it is now of course, but it's not going to kill the engine. Make sure you run good fuel.
2000ft is a significant difference to properly tuned carb. May not be if your mis tuned carb goes to right way so was lean and you go up it'll improve some but a lot plays in when changeinv altitude and air temps humidities etc. Air fuel needs adjusting and needles taper also for best burn.
Some people can't notice difference or don't know enough for proper adjustments. So leave well enough alone. Hell I know a guy his bike runs 3cyclinders outta four and he thinks its perfect but I hear its stumble half mile away.
 

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The point I was getting at is that if you expect to have a "perfectly" running carbed bike all the time then you'd b constantly adjusting it. Humidity can have just as big of an effect as elevation.....when it's humid out do you tune your bike differently and then back again when the weather changes? I'm sure some guys do, but for most, it's not a real world situation.
 

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The point I was getting at is that if you expect to have a "perfectly" running carbed bike all the time then you'd b constantly adjusting it. Humidity can have just as big of an effect as elevation.....when it's humid out do you tune your bike differently and then back again when the weather changes? I'm sure some guys do, but for most, it's not a real world situation.
I tune mine for the conditions espically if plan to change 2000ft of elevation.
I don't tune everytime it get humid or dry but will adjust when its not 100° here. Maybe when it don't get abouve 85. Ill play with air fuel mixture a Lil bit.
Chances of average Joe who only rides to work or once a month he probably won't worry about proper tuneing due to either changes or elevation unless they absolutely have to. Most people are scared of carbs and don't understand fully whats going on.
 
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