OK seeing as is seems there is a substantial body of experience in these forums I will pose the follow question: I have a 98 F3 that I ride around Ohio (elevation 1000) but I am moving to Colorado (elevation 5500) in a few months and I am curious if I need to retune for the substantially higher altitudes that I will be riding at. I know there will be a loss of power if I dont but I guess its a question of how much. I was planning on installing new pipes and a slip-on and rejetting the carbs but I wasnt going to do it right away and will probably be riding in my stock configuration for awhile. Some of the passes I will be riding are over 11000 feet. Thoughts on this?

 

I cant really give any advice, other than to have a shop out there tune it. Preferablely on a dyno with a wideband o2 sensor. I know alot of snowmobiles have a chart stickered on them somewhere that gives recommended jetting, but I've never seen anything on a bike, or in a service manual about high-altitude tuning..

 

tech book calls for,

main jets in carbs 1 and 4 to be #130
main jets in carbs 2 and 3 to be #132

pilot screw opening to be 1/2 turn in.


this is for 6500 feet or higher. in stock format.

 

hey im in greeley colorado an im runnin on the stock jets with an arrow slip on. i've gone up into the mountains a little bit but not 11000 feet but it seems to run fine to me.

 

yea it will seem to run fine till the valves burn out

 

From my understanding, i live in utah ele. 4500 ft, it doesnt matter too much. The higher the elevation the less air you have to burn which means it will run rich. So if you put a slip on exhaust or airfilter it should equal it out.

 

you got that backwards less air at higher alts so it will run richer, or it should, you could put the slip on and be fine.