[wvyankee2]

I'm going to Colorado the first week in Sept. for some trail riding. Anyone here give me some info on how the 450 runs in High Altitude with standard jet? Also What is the purpose of the high speed spark plug that the owners manual talks about. Getting ready to change the plug, and was curious as to whether I should get one. I do alot of high speed trail riding ( for a foreman) Bike has 650 miles and 66 hours so I'm averageing 10 MPH. Thanks.

 

[shooterman]

i can't speak specifically for the 450 but both my 03 ranchers and my 05 foreman run exceptably well at up to 10,000 ft. the plugs get a little sooty but it is better than being too lean. going to paiute trail in one week and i'll have all the hondas over 11,000 ft. and don't expect any problems. i would say that if your atv never goes to a lower altitude, then rejet for where you are at, but optimum jetting for the rockies may leave your atv too lean at lower elevations and that could harm the engine.

 

[jsfcpawv]

Colorado Ride

I have taken 4 Honda's (2005 500 Foreman ES, 2005 400 Rancher AT, 1999 450 Foreman S, 1990 300 4WD Fourtrax) out to Colorado and ridden without having to rejet. They did tend to die over 10000 feet when you came to a complete stop and tried to idle. The 400 Rancher had the most noticable loss of power(It wouldn't climb over the sides of the trailer. The 300 was affected the least. Couldn't really tell any difference from riding WV.

 

[wvyankee2]

Thanks for the info guys.