It could be the result of your carb vent line being submerged. This is fairly common problem on KTMs and some folks go as far as to modify their lines to vent up near the headstock.
It sounds like you didn't suck any water through the intake, so that could be the culprit.
Regards,
Mr. BigWheel
It sounds like you didn't suck any water through the intake, so that could be the culprit.
Regards,
Mr. BigWheel