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Discussion Starter · #1 ·
I am a newbie Harley owner having just bought a 1200C and I'm hooked.
I don't really want to mess with the new bike yet, I like it the way it is--for now.
But now I have it in my head to build a hot street sporty just to mess with the 'busa's and kawi's. I do realize that is a tall order, but is it possible?
I have noticed during my limited research that supercharging these things is not done often, more on the cool show choppers than any performance racing types.

A little background: I have much experience supercharging cars with mud racers, top dragsters, top sportsman, top alcohol, and an insane front engine VW bug under my belt. (All alcohol injected)
I have done some successful turbo stuff too, but I like the look and loud of the supercharged stuff.
I also happen to have a collection of small superchargers to choose from.
It is safe to assume that I can make whatever components I need to drive, mount and plumb this, and I am planning on electronic fuel injection using E85 for fuel. (Alcohol from a gas station--who knew?)

As I am looking into this I find there are many variations of the sporty motor, and at first glance it looks like the one called the "iron head" may be the most promising candidate due to the way the head and cylinder bolt on.
But there is much I do not know.
Like:
Is the 4speed stronger than the 5?
How good is the stock clutch?
and the big question--why is this not a popular mod?

Please weigh in and educate me, I REALLY want to do this.

Kendrick
 

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I think the primary reason is that turbos are more efficient than superchargers, and much easier to implement.

If you go with any type of power adder, you will want to go with an aftermarket clutch.
 

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If your 1200C is EFI there'll be a setup issue. Probably want to convert to carb.
Also IMO, you can get just as much power with a Zippers kit for the money and you won't have a SC sticking in the side of your knee !
 

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Discussion Starter · #4 · (Edited)
Kainam: True, but they are a bit trickier to tune. Who makes a good clutch? Wet or dry?
Schmidtys: Not using my new bike, I am starting from a blank slate..and an idea. I am planning on mounting the supercharger in front of the motor and low. I will probably use an aftermarket EFI system for fuel management.
 

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Discussion Starter · #6 ·
Thanks for the link Kainam, exactly the type of info I am looking for.
 

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I drag race, Got a 68 chevelle SS with 396. Love supercharged over turbo as no lag time. You have a great idea, I have never seen a supercharged Harley. Get started on that project keep us posted on progress and post lots of pictures.


Sent from Motorcycle.com App
 

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Sounds like a fun project, but I dont know if you will end up with a bike that will beat the busa's and ninja's. Even with a supercharger do you think you will even be in the 150 hp range? They will have the right aero dynamics and transmissions for 150 to 175 mph. Sportster tires wont even be rated for that speed.

Not trying to bust your dream but I have never seen anything like this done on a street ride before. Good luck and keep us posted.
 

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Way back in the day I had a supercharged 72 Sportster. I ran it for two seasons with the stock clutch and had no problems. But, I will say that I was not doing a lot of full out street racing.


 

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Discussion Starter · #10 ·
Ultra Struck: I agree, and there may be very good reasons why this hasn't been seen, and more than one obstacle to overcome, but my 2.4L VW engine was making 375 -425 HP (9 second ride in the 1/4) so 150 -200HP in a 1.2 L is doable IF the motor will stay together. I'm looking for a light to light embarrassment potential more than a top speed machine.
ducedog: Very cool. Is that a centrifugal? How much boost did you run?
 

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Ultra Struck: I agree, and there may be very good reasons why this hasn't been seen, and more than one obstacle to overcome, but my 2.4L VW engine was making 375 -425 HP (9 second ride in the 1/4) so 150 -200HP in a 1.2 L is doable IF the motor will stay together. I'm looking for a light to light embarrassment potential more than a top speed machine.
ducedog: Very cool. Is that a centrifugal? How much boost did you run?
Hope it works for you. Like I said, keep us posted.
 

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My .02 cents here...

Buy or make a lightweight rear swingarm, use Buell front forks or xr1200 inverted front forks and get yourself sport bike tires. You will need/want the grip and speed rating to be safe.

Then get yourself the biggest brakes you can, two up front one in the back..you need to handle and stop this beast safely too.

I'd consider maybe having plastic fenders and gas tank made...that's up to you though just to save on some weight.

I thing for engine I would use the Evolution 1200 (73ci) bored out all the way to 88ci (there's a kit for it) with appropriate heads and cams.

This way, you are relying on the supercharger for less power so you can keep boost pressures down and have a more drivable bike.

Just my .02 cents.
 

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Man I hope this thread stays alive as this topic is hot. I am excited for you Kendrick, please keep us posted and maybe even photo or video journal the build. For The Win!
 
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