1 piece jug third transfer, boost port, and more

[Jug]

Decided to port my 1 piece 80/66cc motor
This motor came with a fm80 crank, and really good transfer ports for a stock motor. But i needed more.

Made window small for more low end

Third transfer, boost port, some transfer porting all done. I made the third transfer and boost port awhile ago but i just bored it out more. I also had one of those s**tty amazon double window piston which didnt even line up with the boost port. So i made my stock piston with a window and upped the intake timing an extreme lot. Im running a dio reed with a 21mm PWK carb, i think its gonna be a beast.
Also upped the exhaust duration up to 168, and rounded it out.

 

[Frogslayer]

It looks blown up lol. Are you just practicing or will this really run with the scores and such?

 

[Jug]

Their are 3 variations of "Boost Ports" this one requires a reed and strong pulling pipe.
Being the boost port is lower then the main transfers, it won't work as pressure bleed.
It will be open right around BDC to fill the cylinder if the cylinder pressure is right.
Usually you want to start narrow port and 30* angle. Then widen and increase angle till matches the wanted output.

Im running reed and this is my first time doing boost ports. I need to get a pipe tho...

 

[Jug]

It looks blown up lol. Are you just practicing or will this really run with the scores and such?

Its blown up 2 times lol, still runs fine

 

[Street Ryderz]

This is a proper boost port,there is no trench below it as that is bogus and does nothing! A boost port for reeded engine is meant to open with the transfers to give more cross sectional area for the pipe to draw on.This port is generally a separate window above the intake port window and not combined to it as they both do different things in the cycle.What you have here is not really going to do much other than increase intake duration.

 

[Sean503]

....uUuuh. RiGhtT ! Lol. Hmmmm

 

[Karl Snarl]

....uUuuh. RiGhtT ! Lol. Hmmmm

It's ok, I bet if you ask him nicely, he will help direct you down the right path to power.

 

[Member 30571]

^^^^Jug : Last Seen Feb 2021.... Don't hold your breath for a reply..

 

[Frankopie]

This is a proper boost port,there is no trench below it as that is bogus and does nothing! A boost port for reeded engine is meant to open with the transfers to give more cross sectional area for the pipe to draw on.This port is generally a separate window above the intake port window and not combined to it as they both do different things in the cycle.What you have here is not really going to do much other than increase intake duration. View attachment 95218

And I'm even messed up even more now I don't know what to do

 

[Street Ryderz]

And I'm even messed up even more now I don't know what to do

In these bicycle engines a windowed piston is all that's needed for the use of a reed, the cylinder is not configured correctly to do a proper boost port and trenching above or below the intake port just eats pistons up with no real gains to be had.