won't start after it warms up

[dsrtdog]

A friend of mine rides an 02 426.The bike starts up good when it's cold,but when it's been ridden for a while and try's to re-start it he kick's until he's a puddle of sweat.The carb is jetted with a 158 main.We ride at about 4500 ft+.Any help would be appreciated.

[sirthumpalot]

Is he using the hot-start knob (the red knob next to the choke)?

[fatmancantfly]

Sounds like an clogged primary jet.