Never really thought about doing one of these side exhaust engines But Jim Calcagno out in Oregon has been casting up some super cool custom stuff off and on out of his shop recently and they have been givin' some love to the side poppers with a couple of neat exhausts. The most recent one he offered is a megaphone style and as soon as I saw it :drool:......... I had to have one!!!!!
I contacted Jim after seeing one of these on ebay. I was not sure if he was going to do more of them or not, and being the super nice guy that he is, said he would run a couple more. I just got it today, had to get it on something to see how it looked and how it would fit on a frame. Its got a good flare out so its not exiting right on the frame and looks like it wont poke too much farther out than what a typical chainguard would out the side. I would not want it on a mid peg bike but It should look sweet on a small forward peg frame right atop the chainguard!!!
The block its sitting on is a mid 80's 3.5 large valve. Tecumseh upgraded the crankshafts by that time and started to use the HS40/50 crankshafts and con rods in these. The downside is the taper on the cranks in the 80's is larger so you can only use the steel flywheel. They do still interchange with the older HS40's So my evil plan is to install an early HS40/50 crankshaft, and use an HS40 73-down flywheel so I can use the 73'down curved shroud on it. cant fit the Billet con rod in these blocks though (they dont have that little clearance hump section that the HS engines do on the frontside) so don't want to make screamer out of it or anything, but The HS rods and cranks alone are just beefier/larger units so it should add a little strength to it.



I contacted Jim after seeing one of these on ebay. I was not sure if he was going to do more of them or not, and being the super nice guy that he is, said he would run a couple more. I just got it today, had to get it on something to see how it looked and how it would fit on a frame. Its got a good flare out so its not exiting right on the frame and looks like it wont poke too much farther out than what a typical chainguard would out the side. I would not want it on a mid peg bike but It should look sweet on a small forward peg frame right atop the chainguard!!!
The block its sitting on is a mid 80's 3.5 large valve. Tecumseh upgraded the crankshafts by that time and started to use the HS40/50 crankshafts and con rods in these. The downside is the taper on the cranks in the 80's is larger so you can only use the steel flywheel. They do still interchange with the older HS40's So my evil plan is to install an early HS40/50 crankshaft, and use an HS40 73-down flywheel so I can use the 73'down curved shroud on it. cant fit the Billet con rod in these blocks though (they dont have that little clearance hump section that the HS engines do on the frontside) so don't want to make screamer out of it or anything, but The HS rods and cranks alone are just beefier/larger units so it should add a little strength to it.
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