Hemi with a non hemi head build

Awesome job KMC ! Engine is looking great and should be a nice lil ground pounder ! :thumbsup::thumbsup: I love the engine wrap !
Awesome job KMC ! Engine is looking great and should be a nice lil ground pounder ! :thumbsup::thumbsup: I love the engine wrap !
Thanks buddy! I am impressed with the decal as well. A guy over on bobs makes them for a decent price. My wife's maiden name is Hudson, so in an effort to buy them I told her it was all for her. Obviously, she bought it lol.

I have vented my crankcase to revert any oil back over my valve train. I have also put a barbed fitting to run to my catch can. Maybe overkill but I am under the impression that venting is a good thing. I used a 1/4" NPT tap for the barbed fittings which I purchased from Home Depot.

Does anybody have a recommendation on jets for the Mikuni? It currently has the 30 Pilot and 100 main jets, but this is my first go with the real Mikuni.

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Your intake seems to be round where it mates to the head and overlaps quite a bit. You may want to roughen it up about 3/4 inch up from the mating surface where it meets the head and fill it in with JB weld then taper it to fit the D-Port of the head. I have had to do that on a couple of homemade manifolds. It really helps airflow.
I know you purchased two of these, so for others that might be curious about the intake. It matches the D port of the head amazingly well, the taper is very nice also from the O to the D.



Supporting Speed Nut!
I tried selling this motor a while back and no luck, so I am just going to build this and document the progress in this thread. This motor is a hemi bottom end with a non hemi clone 18CC head:
ARC +.040 rod
Hemi flat top piston milled .005
pop up is +.015(above deck)
Will be using a .045 fire ring head gasket
Head is 16.3 CC for 12:1 compression
28/25 SS valves
dual springs
1.2 Ratio rockers
Hardened pushrods with guideplate
Will be running a black mamba sr cam
Debating on running a genuine honda side cover or the hemi cover at the moment.
I am waiting on a 3/8 barbed hose fitting for crankcase venting currently.
Progress so far:

Sounds like a good build, not to radical
I ordered a 120, 125, and 130 main jet. I ordered a 15 and 17.5 pilot jet. I purchased these from jetsrus.com

One thing I found interesting is the below statement on their website, and seems helpful to me, as well as reading the spark plug.

"If the bike seems to be lean then partially cover the intake to the air filter housing with duct tape, if the carburetor improves it is running lean.

If the bike seems to be rich remove the airbox cover, if the carburetor improves it is running rich."
Motor Mounting

My motor is complete, I have installed all tins, and have it sitting on my Gilson frame. I am waiting on jets for my carb, fuel line, Mikuni throttle cable, UNI air filter. I found my quart of break in oil and am ready to fire this thing once my parts arrive. I still have to install my gas tank, but am waiting on my fuel line to run my crank case vent to my valve cover.

In for vids of it making passes soon!
Same here. I got it fired up this evening, I did not have my throttle cable hooked up or my chain hooked to my clutch. Gotta get those hooked up and can go for a test ride to seat the rings. The carb seems to idle nicely, but only let it idle for a few seconds. Excited to get this thing on the road.
Few pictures. Might be sideways. Uploading from my phone. I ran my fuel line through the choke lever and around the slide so as to keep the fuel line somewhat level. I also put a fuel shutoff valve inline.


My bike/motor is complete. The very last thing to do is tighten my muffler and experiment with carb jets. I am fairly certain I will have to order a smaller 12.5 pilot jet. I still need to move my needle clip to see if that makes a difference. Didnt have a ton of time to tune. I did get to ride the bike for about 45 minutes and made some pretty good passes. The rings are good to go. I need to change the oil and then start tuning on the carb. As you will notice in the video, my recoil is a predator 212 black one. The recoil I was using was obviously disassembled for powder coating, and the handle came untied after a few pulls. So I switched recoils as I tried to fix the original one, and the spring got loose :hammer:

Air Filter:

Short run video. The carb is idled high, but pretty responsive:

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