Porting a 2 stroke cylinder

[Mathematica]

Where do I start with porting? Is porting useful without a reed setup? If it is useful, what aspects of porting should I go with? The various aspects of porting generally include raising/lowering exhaust + intake, windowing piston, widening exhaust + intake, and adding a boost port. Should I combining all of these porting aspects on one cylinder? Is there a comprehensive guide I can follow step by step to understand how much material to remove?

Finally, explain to me why I might want to port my cylinder. Step by step, what should I do to get started if it is indeed useful without a reed setup.

I've heard that basic porting involves raising the exhaust and lowering the intake by 1mm. As well as widening both the exhaust and intake ports by 1 mm. If this is a general rule, what do you need a degree wheel for? Could I just port and go without doing calculations? What are the calculations for?

 

[GW's Motorized]

Basic port corrections and port timing corrections are as far as I would go. Porting cylinders may sound easy, but it is very easy to make the cylinder go from an absolute screamer to an expensive paper weight. Just do the raising and lowering of the ports, smooth out any rough spots, and polish the exhaust port. If you want to window the piston you will need a reed

 

[Mathematica]

Basic port corrections and port timing corrections are as far as I would go. Porting cylinders may sound easy, but it is very easy to make the cylinder go from an absolute screamer to an expensive paper weight. Just do the raising and lowering of the ports, smooth out any rough spots, and polish the exhaust port. If you want to window the piston you will need a reed

gotcha. So you're saying raising the exhaust and lowering the intake is all I should do? How much should I raise and lower them by? From what I've read, raising the exhaust and lowering the intake gives a broader mid power band. If I add a jog pipe expansion chamber, how would this affect my porting? Would I have to do entirely different porting if I want to add the expansion chamber? If so, would no porting with an expansion chamber be better than porting without an expansion chamber?

 

[cloakedvillain]

MOTORIZED BICYCLE PERFORMANCE MODIFICATIONS FOR CHINA GAS GRUBEE ENGINE

www.dragonfly75.com

 

[Mathematica]

MOTORIZED BICYCLE PERFORMANCE MODIFICATIONS FOR CHINA GAS GRUBEE ENGINE

www.dragonfly75.com

hell yeah, thanks man

 

[GW's Motorized]

Another way to make good performance is port matching your intake manifold to the port, and your exhaust flange to the exhaust port