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Discussion Starter · #1 ·
I started by putting the bearings into the cases, crank, piston and cyld today, marking the mods with my Sharpie felt pen. With No base or head gasket the piston sticks up .115" which was exspected, and it hits the crank at the bottom too. Going to have to make a spacer, .085"- .115" depending on if I run 2 or no base gaskets between it. The one ring pistons 12mm bearing is to small for the Cag rod, so I put a 12mm Cag bearing in which has a bigger OD. Might send the cyld to Sam and have him put the 2 upper intake ports in. Wanted 1 big port, but the piston has a pin for the ring split in the center which would be inside the the upper port so one on each side would be better.
The piston needs all kinds of grinding and 2 boost holes.
 

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Discussion Starter · #3 ·
Going to put it in my Razor Rocket gas conversion bike, w/ Cag wheels. Going to put rectangle tubing extenders on the rear arms. Alot of work left on this engine. The plan is, light everything, high compression cap modded to clear the piston top, lots of rpms. Going out pretty soon to grind the bottom of the piston to clear the crank,lol. Then put it back and look at the exhaust ports & main transfers to see if the piston blocks the exhaust port hole,lol. Then grind off any of the piston skirts hanging out the bottom. Got to find some .090" to .104", 10 gauge alum or copper thick sheet material to make a lower cylinder spacer. Want the cylinder and piston top to be flush. It's a 40mm cylinder and a 44mm 17:1 Comp. Cap and .020" copper head gasket. That gasket will let the piston clear the head piece, and give me killer Squish,lol.
 

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Discussion Starter · #5 ·
I dug out a 40mm stock cylinder I had today, cause there is more head room. It took 2 paper and 2 .020" copper base gasket to just miss the top, so I added a 5th .010" copper gasket which gave me around .085" of cyld lift. I need .150" on the 2pcs ADA kit. I started cause someone said there crank only had a 30mm stroke, I think it was a new piston port with the 42.7mm bore and 30mm stroke that they advertise as 49cc. I checked 2 cag stock cranks and my FC crank, believe there all 32mm. Any way I still needed a spacer of some kind on either one, don't know if 5 base gaskets are going to cut it. Have to go look for some .104" to .125" alum or copper plate and cut a cyld spacer, might make 3 at once stacked, for some spares,lol.
 

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Take a bad cylinder and lop the flange off and the cylinder skirts then beltsand it flat on both sides...Itll have the proper transfer port shape n everything with hardly no work....Thats what I did to make a spacer for under the head of my dual carb hybrid engine when I built that...
 

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Take a bad cylinder and lop the flange off and the cylinder skirts then beltsand it flat on both sides...Itll have the proper transfer port shape n everything with hardly no work....Thats what I did to make a spacer for under the head of my dual carb hybrid engine when I built that...
lol BINGO!!!!
 

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lol BINGO!!!!
Yeah thats the easy part....making sure the piston top is gonna clear the bottom of the exhaust port fully at BDC is whats the mystery....

before I chop the flange off to make the spacer I would use washers under the head set to the right height to make sure first................I have a feeling at BDC the exhaust port is gonna be a tad more than 3/4 open with that piston pin to piston top offset//
 

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Discussion Starter · #10 · (Edited)
That's what I checked on both cylinders, on the ADA It takes about .150" spacing for the piston to be level at the top, and the stock one .085-.090" to just clear the top. Both cylinders the piston top is level with the bottom of the exh port at BDC, I was shocked. So, will probably use the ADA cyld. Thinking about my 17:1, 44mm cap & copper gasket on the 40mm cyld it gives the piston more clearance so it don't scrape the copper gasket if it goes up that far. I have a bunch of 40mm and 44mm caps in 15, and 17 to one. Dave's was selling them for $3, there near $30 some places.
I picked the 17:1 also cause with one ring might not seal as good on the compression stroke as 2 rings,lol. Thinking about modding one of the ADA 3D billet Cag manifolds I got onsale for the 15mm X2 type pumper carb. I have 2, will look to see if I could mod one to fit the other WT-813 Walbro I got,lol.
Had to put the crank bearings in to really tell where the piston was at, so I will duck tape both sides when I grind on the cases, still have to add 2 upper intake channels and and mod the main transfers and match the cases to the cyld. If I had a BridgePort I would put a flycutter in the Quill and take some off the cases where the cyld mounts, might still need to use 2 .020" copper base gaskets and copper spray,lol.
It's going to be 80 to 85 degrees for the next few days need to tack weld the rear arms on the A2 Polini frame while the weather is good,lol.
I am still in shock from pictures from Staten Island and New Jersey coast line. Looks like Japan after the big wave.
 

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That's what I checked on both cylinders, on the ADA It takes about .150" spacing for the piston to be level at the top, and the stock one .085-.090" to just clear the top. Both cylinders the piston top is level with the bottom of the exh port at BDC, I was shocked. So, will probably use the ADA cyld. Thinking about my 17:1, 44mm cap & copper gasket on the 40mm cyld it gives the piston more clearance so it don't scrape the copper gasket if it goes up that far. I have a bunch of 40mm and 44mm caps in 15, and 17 to one. Dave's was selling them for $3, there near $30 some places.
I picked the 17:1 also cause with one ring might not seal as good on the compression stroke as 2 rings,lol. Thinking about modding one of the ADA 3D billet Cag manifolds I got onsale for the 15mm X2 type pumper carb. I have 2, will look to see if I could mod one to fit the other WT-813 Walbro I got,lol.
Had to put the crank bearings in to really tell where the piston was at, so I will duck tape both sides when I grind on the cases, still have to add 2 upper intake channels and and mod the main transfers and match the cases to the cyld. If I had a BridgePort I would put a flycutter in the Quill and take some off the cases where the cyld mounts, might still need to use 2 .020" copper base gaskets and copper spray,lol.
It's going to be 80 to 85 degrees for the next few days need to tack weld the rear arms on the A2 Polini frame while the weather is good,lol.
I am still in shock from pictures from Staton Island and New Jersey coast line. Looks like Japan after the big wave.
Yeah there were some spots that were pretty hard hit.......The problem now is theres a huge gas shortage and theres a Noreaster on the way....
 
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