7900 experiment

OK i'm a older gear head how can you adjust timing on a 2 stroke, base gaskets or coil or both??

 

Ignition timing? Or port timing?

 

Ok how can you alter port timing, no valves so to speak of?? Do you egg the holes out of the coil or do they make a offset ?

 

Rotate the flywheel on the crank.

 

Or like mike said grinding off the key and reclocking the flywheel.

I get how they do it in theory is all. I am a newbie and really lay person when talking all this stuff.

 

Yeah... And sometimes we just sorta pokem' with a stick, and put em back together, hoping for the best...

 

Can do it by just shaving on the oem piston too. Bottom of intake skirt etc. For those on a budget gain.

 

Or a file to the edge of the crown where the transfers open...

That's very Redneck of you Kevin...

 

That too. I actually had that in my post then edited it out.

 

That's the easy way to do it before grinding a jug.

 

What's a grinder?

 

Definition of Grinder- a machine that sucks whatever is in your hand out of it a flinging it in some weird direction while simultaneously removing finger nails and finger prints. It can also be used to test the sensitivity to heat of ones fingers.

 

FYI a 390 boot makes it harder to fit the air filter and choke linkage.

 

Actually have seen both of those methods used by none other than Husqvarna on race motorcycles. Crude but sometimes the quickest most cost effective method. I would not trust extensive use of it on the cast pistons we have in saws. Perhaps on billet racing pistons.

 

Cheap and dirty...

 

Several well known shops out west use the trim the skirt method. So it must be ok for chainsaw pistons.

 

I did not know that. Thanks for posting that info. I wonder if there are limits to what you can do before you have to mess with the ports. Obviously short circuit is a governing factor.