I am looking for pistons for an iron 4G. My bores are currently +0.020" but are in need of a rebore. I am investigating a number of options but would appreciate some advice/experience please. My choices seem to be:
- Source some decent used (or NOS) standard pistons;
- Use Draganfly Mk2 +0.040" pistons;
- Use IMD Mk2 +0.040" pistons.
I have looked at some used hepolite pistons but, by the time I factor in new rings and gudgeon pins, the cost would be more than the new Mk2 pistons. I would however prefer to keep the low compression feel to the 4G engine.
Draganfly says that Mk2 pistons will up the compression of a 4G engine to 6.9:1. Has anybody had experience of machining Mk2 piston crowns flat to keep the compression ratio closer to the standard 4G ratio of 5.8:1?
What is the difference between Draganfly and IMD pistons?
Thanks in advance, Pete