ridden throught the desert in 110-120deg and was hualing *** never once has it come on this bike runs cool, try hooking the fan to 12 volt to see if it spins up

 

I checked the circuitry per post #4. Fan, relay, and fuse all good. The fan switch is bad per the diagnostics described. When I rode hard through the desert on hot days, the fan never came on because there's enough airflow through the radiator to not need the fan. But when I'm climbing 20%+ grades in 1st gear at less than 5 mph for over a mile through loose shale on a hot day, the fan (used to) come on.

 

My fan (07 model) has never come on that I know of - even on steep, rocky, slow stuff. Course I'm in a cooler climate as well - Maine, so I always thought it was that. Looks like others have the same experience even in warmer climes.

 

Yes, this bike's fan doesn't run much, but mines been on many times last year so I know when it should turn on. I could watch the Vapor computer and see it coming. Has your bike boiled over? I got to think the fan should come on before it boils over, unless perhaps the radiator cap is shot.

 

Yeah, Scott, this is one of the things I really like about the Vapor. That coolant temp sensor really keeps you informed about how the engine temp is going. My fan came on 2 or 3 times this last Colorado trip, and that was because of the gearing and bigger tire issue we talked about on another thread. The 2 years before it never came on with the shorter tire. That bigger tire deal made just that little bit of difference with my 14/47 gearing. I don't think it would have come on this trip with my current 13/47. I just realized that I'm just about equal to stock on the KLX300's OEM 14/50 gearing.

 

My fan came on a number of times while we were doing Moab last year, but yours never did? Interesting. It surprised me that it would come on going down hill at a slow pace on those hot afternoons. I may replace the rad cap too, but I must think the switch is questionable after finding it testing the way it did.

 

Try to run your ride on neutral fit like 5 minutes with occasional throttle that should turn it on in no time.

 

Unless its 100 degrees out and you are riding in first gear uphill on a single track trail, it probably never will come on. Mine only came on once under those conditions. After 15,000 miles I figure its the norm.

 

One of the wires is very poorly grounded to the radiator under the right side radiator shroud. Scrape the paint shiny and tighten that fastener,