Piston skirt mod and regaining bottom end

[JerboaJohn]

I ground my 48cc piston skirt to uncover the full intake port at TDC, and it's great at upper mid to top end but feels like I lost some on the low range. I understand I changed intake port timing/duration since it wont close the intake port sooner, but how could changing bottom gaskets give me back a little more bottom end? I dont see anyone listing bottom gasket thicknesses I could choose from.

 

[crassius]

adding too much there will lower compression and change timing of other ports - gets complicated pretty quickly

I'd get another piston and kind of sneak up on the skirt cutting just a bit at a time until I had the amount I liked, then stop there.

 

[JerboaJohn]

yeah I won't get carried away with the piston this time. I have a new jug and piston to play with now. I forgot I ordered one last week doh!

 

[Lukesky36]

I Grounded my piston skirt not long ago yes it does move the power band up higher but could i say it effects the fuel ratio at different powerbands. now this is just a theroy but i believe a skirt cut makes the engine less rich on the low rpm with a skirt grind since it has less of a pulse effect on the port. i have a very steep hill i hill climb and the power too climb it is not much different since i skirt chopped it try playing with the choke very slighty to get alittle more fuel and see if that adds torque it did for me

 

[JerboaJohn]

thanks, yeah hat makes sense about the pulse. a piston is cheap so next rebuild on this one or the next 2 stroke I put together I'll do it differently.
now if I could get more rpm out of it I could take advantage of more flow. it only revs to barely 5000

 

[Lukesky36]

i have a 66cc/80cc its a
Seeutek PK80

pk80 rod/engine and yes i checked its a real pk80 runs great but the balance factor is off even though its a balanced crank at mid-high to high rpm range, high rpm it screams like crazy and its smooth and it wants to keep going