bychance
New Member
Hi, I got given a 2007 Atomik bike with a 125 Ducar motor last week. Some parts were missing, so after fitting a new throttle grip, carby and flushing the motor, although it started easy, it blew heaps of blue smoke. I stripped the engine to replace the piston and rings to find that the piston was seriously stuck on and would not even wobble on the gudgeon pin. Some movement was possible but it wouldn't move easily. I made a puller to pull the pin out and found it would move the pin within the piston (or move the piston back and forth 4-5mm on the pin) but it was stuck on the little end (yes, I removed the end spring clips). I even tried a huge "made in England" G clamp to push the pin out and bent the clamp! Next I cut the piston off by splitting it down the middle to reveal the stuck gudgeon pin on the little end. I then made 2 flats on one end of the pin with an angle grinder to try to at least rotate it with a spanner, still no movement. I will try some heat today to see if that works. Has anyone had this happen before? I'm guessing whatever eventuated is that the little end will be ruined by now, it may have been one of the causes of all the smoke as the piston was not able to rotate much at all on the gudgeon. Has anyone had success at drilling a gudgeon pin out? The next step may be to split the crankcase/gearbox and get a new conrod- I am trying to avoid this. Cheers, Marco
Last edited:
