Hopped up motors

[Frankenstein]

I got you. I didn't realize you weren't aware that these were reed valve engines. What a mess it would be without one.

I think your right about the slower throttle response due to the volume of the reed housing. I considered stuffing it like I have read about somewhere on here. I think it was Steve. I,m just unsure about putting jb weld right where everything goes into the engine.

I have jb weld (and probably 90% of motocross RACERS) in my transfer ports in the cylinder. It won't hurt a single thing. Just make sure you clean and rough the surface up a bit so you don't lose anything.

 

[gary55]

Are you just using it on the back side for better direction to the front of the cyl.?

 

[Steve Best]

Frankenstein, you were right it will run without a window in the piston skirt.However it won't run well at high-speed. The main flow needs an unfettered path to the crankcase.

Gary, Do the job well and the epoxy will hold. "Trust Luke, let the force be with you".

Typically the boost port is just a fifth transfer port, so it is the same height as the others. To make one higher than the others, is to take from the flow of all the others.

 

[Frankenstein]

Frankenstein, you were right it will run without a window in the piston skirt.However it won't run well at high-speed. The main flow needs an unfettered path to the crankcase.

Gary, Do the job well and the epoxy will hold. "Trust Luke, let the force be with you".

Typically the boost port is just a fifth transfer port, so it is the same height as the others. To make one higher than the others, is to take from the flow of all the others.

So would doing both just end up lowering precompression then? Seems better to just cut a window in your piston. Unless you are looking to tune for strong low end and couldn't care for top at all..

Are you just using it on the back side for better direction to the front of the cyl.?

Yes, it comes in contact with my piston rings as well. I set the cylinder on its side with some tape at the end of the transfer, and put epoxy in to help precompression while also angling the direction of my transfers (preferably towards the back and slightly offset for max chamber fill.) I touch up the angles and edges a bit with carbide bits.

 

[Steve Best]

Yes I would suggest to do both. When the intake port is blocked it's good to have an alternate path around to keep flow moving. The best answer would be to experiment.

 

[Frankenstein]

Yes I would suggest to do both. When the intake port is blocked it's good to have an alternate path around to keep flow moving. The best answer would be to experiment.

One of my favorite words.