My son's rev3 125 2006 is a pig to start once warmed.

The bike goes pretty well but needs quite a few kicks to restart.

We have recently replaced the barrel due to an overheat and revised the whole lot including carburettor cleaning and new plug but she is still refusing to start properly when hot.

Any ideas?

Faulty HT coil can cause this.

Thanks dado, shall look into that

Put a spark gap tester on the bike

If it jumps a 15mm gap then you have no ignition problems,

First basic beginning of diagnosis is Spark or Fuel, eliminate one and you can stop feeling you're way through the dark

Good luck