i tried to get the stock intake boot over the 38 keihin and gave up and just bought the ESR kit. im satisfied with the bigger carb on the 250 vs the stock carb so i guess i gave a little to get a little.

 

Odd, I got mine over the 39 pwk (bored to a 40.5) without a problem. The trick is to pull off the airfilter from the boot, reach in from the inside of the boot and work it over the intake of the carb from the inside.

 

i think i was trying to slip it on using a small flat head being careful not to damage carb in any way by creating ugly gouges in the outer part of the inlet. ill be switching to a 39 soon and just as well.

is the stock intake boot on a trike and trx the same as far as diameter? i would think it would be.

 

I believe it is.