thats dissapointing that a correct period watercooled kit for that bike is not allowed even if there is proof that is is a period accessory part (which i know there is). but i guess rules are rules. perhaps the rules can be changed to include the aftermarket watercooled kits from Fox, Lop, shinobi, Mugen etc? what about home made conversions too? they could be allowed. people certainly were doing there own watercooled conversions ( barrels as well, not just heads) back in the 70's to early 80's and ive even got old magazines that tell you how to do it.
but i guess the bottom line is EVO - NO water cooling so you cant argue with that.