Hello,
I'm a new member but have used this site for years for great info when working on my trikes. I presently have a 1985 ATC70, 1985 ATC125M, and a 1986 ATC350X. I'm about done with the 125m and just refreshed the top end with a new piston, cylinder bore, fresh valves and had the seats reground to match. After reassembling everything according to the service manual, I still have the same smoke issues I did prior to the rebuild. I did notice the one of the channels that feed oil into the top end was corroded and i bent one of the dowels when trying to remove it. I think this same dowel may have been leaking oil into the cylinder before as I had great compression and the old piston I replaced looked beautiful. I plan on replacing the dowel once it gets here (just ordered) and I wanted to see if anyone could chime in to tell me if it could cause the smoke issue (it wasn't bent before I tore down the top end but maybe the corrosion could lead to this too). Also, does anyone know how to get the old dowels out when they are stuck in place without bending them? Thanks!