Just to clarify the 3rd transfer port mill work at the bottom of the cylinder was cut with a 15/16" side mill the end mill was used to make the short upper cut (7/16" wide) above the intake port, to the height of the other two transfer ports. Depth of both 3/16".
After the last post I decided to finish the expansion chamber conversion to muffled status. I had previously cut the back section off, leaving about 3.5" of tube. I then cut most of the pipe off of a stock kit muffler, leaving about 3" of pipe which was then slipped over the short length of tube on the expansion unit. I used a Harley tube clamp to secure the slip jointed pipes after having double slotted the outer tube for the compression fit...it's not coming loose! I'll use the clamp to support the rear to frame with a bracket not yet built.
I tried the pipe with and without the muffler on both the X-celsior Schinn and the Grubee Skyhawk a couple of days ago and the muffler really quieted both well and I couldn't tell that it killed the mid range much at all especially on the Schwinn and so I've flip flopped once again & will mount the pipe on the Schwinn. It felt pretty peppy with the mods I'd made to that point, no speed racer of course. I think it's a great fun
little cruiser though...Rick C.
After the last post I decided to finish the expansion chamber conversion to muffled status. I had previously cut the back section off, leaving about 3.5" of tube. I then cut most of the pipe off of a stock kit muffler, leaving about 3" of pipe which was then slipped over the short length of tube on the expansion unit. I used a Harley tube clamp to secure the slip jointed pipes after having double slotted the outer tube for the compression fit...it's not coming loose! I'll use the clamp to support the rear to frame with a bracket not yet built.
I tried the pipe with and without the muffler on both the X-celsior Schinn and the Grubee Skyhawk a couple of days ago and the muffler really quieted both well and I couldn't tell that it killed the mid range much at all especially on the Schwinn and so I've flip flopped once again & will mount the pipe on the Schwinn. It felt pretty peppy with the mods I'd made to that point, no speed racer of course. I think it's a great fun