I have a 2001 90 Scrambler, runs for about 50 feet & dies, after it stops electric starter barely spins it, kicks over fine but won't start again for about 5 minutes, then same thing. I just got thru installing new piston & jug, new carb with electric choke. Just needed to replace the choke it wasn't working right but I thought I was purchasing just the choke but was surprised when the new carb came in, FYI the new carb is longer in height than the original if anyone thinks that might be the issue. Tried moving the needle around , check gas petcock getting good gas.. I installed piston with arrow pointing down or front of motor.....I am baffled. Need a Good problem solver!!!!

 

When it dies have a spark plug handy that you can ground out to see if you may be loosing spark. If you have plenty of fuel,have spark,but runs a little ways then dies and won't start again until it cools down,you might want to check compression even with a new piston and rings.Saw that you do have a new cylinder,but still not a bad idea to check compression when this happens.Plus pull the gas cap off and see if that helps on running. A kinked tank vent may be causing a vapor lock.