I think a lot of us that have done the mod take it for granted and just forget to mention it.The gas tank vent problem is well known even at low altitudes. There's a Facebook forum for the KRX and a large group of the members are southeastern trail riders. Hatfield McCoy, Black Mountain, and many others. That was how I learned about it. I am surprised that I haven't seen it mentioned here.
Wow I was just on a 122 mile trek with 1/3 of it about 9000 feet and the highest at 11,672. In general no problems.. actually up to 60 MPH above 11,000 feet!First time out in our 21 KRX to Colorado high country. The engine is very sluggish above 9000 ft and it gets much worst on up. Is there a fuel controller or reflash that will help!!
To be serious which to difficult for me at times. Are you visiting from a lower altitude or purchased the krx in another state. First reason up here for poor performance is lack of oxygen . Fuel air adjustment ,air filter blockage,fuel delivery problem,plugs. Haven't had any problem with my krx at high altitude, other than waiting on razors,can am's to get out of the way. (Just kidding) good luck let us know if you do the tank mod and if it makes a difference. If it does I'll order mine just in case.At that elevation in Colorado you always have to worry about marmots crawling in and messing with your throttle linkage.just like the beavers in the yellawood commercials![]()
I don't think I buy that. Maybe in the days of mechanical fuel pumps mounted on the engine, but not with electric pumps sitting submerged in the tank. A little pressure won't hurt anything, but some of these are excessive. Probably even more so here in Colorado. You fill up at home in 50 degree weather at 5,300'. You get out and ride and end up over 11,000' and near 80 degrees (plus the heat from the coolant lines that split the fuel tank). The combination of heat and altitude gain builds tremendous pressure in the tank. Same is true with my tires. They will build as much as 4-5 psi in those same situations. Doesn't sound like much until you consider that's nearly a 50% increase.I can imagine circumstances where a positively pressurized fuel tank would reduce pump cavitation potential and increase flow by increasing suction side pressure. Wonder if it is designed that way?