i just bought a kq 450,and the dealer said he changed out my factory paper filter and put a uno foam filter,this was done at Suzuki's request,he's saying; anybody heard of this;when i first start my 4-wheeler,it idles normal,after it warms up it idles way to fast, on a 75 degree day, could it be where they changed the filter to the foam one and put oil all it,it may have the computer messed up...i think the carbs are far better until they work the bugs out of these computers. a couple of years now and still having problems,go figure,...........

 

I don't believe that an airfilter change will affect the idle RPM. I have EFI on my Suzuki LTR450 and I have had nothing but perfection with it. You should have the dealer look it over.