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we are 138
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Does anybody know if anyone has ever transplanted the 1500cc kawi ski motor into a bike frame? There's a supercharged version that puts out a claimed 300 HP.
According to my research its based off the zx12 motor.
 

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GURU of da poo poo
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Isn't it based on the ZX14? I would think the best way to go about it would be to start with a 12 or 14(which ever it's based on) and throw the jetski motor in it with the motorcycle trans.
 

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Find a BMW bike dealer, and take a 180hp S1000 for a test drive. BMW dealers will literally hand you the keys to any bike you want on the spot. Find a highway with a lot of room, and snap it to the stop through a few gears. I highly doubt your impression will be "you know, this is decent, but it really needs another 120hp". Mine was to pull over and check if I had just pissed myself. It's absolutely terrifying.

Seriously, 300hp would be totally unusable on the street unless it was so nannied down, you can never actually use it, in which case what's the point?
 

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Seriously, 300hp would be totally unusable on the street unless it was so nannied down, you can never actually use it, in which case what's the point?
:what:

The point would be to have a 300hp supercharged bike.
 

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moron with a hammer
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Figuring out how to cool it will make figuring out how to get it into a bike chassis look like cake.
 

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Actually I think that would be the least of your worries. Sure you'd need a hefty radiator but sure there's something out there that would work. I'm not sure if those motors use water pumps, some use a closed loop system to a heat exchanger on the hull, but some use raw water and it just scoops a little out of the jet pump to force water through the motor.

The bigger challenge is that the jetski motor lacks a clutch or transmission.
 

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moron with a hammer
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See... I like dangling things like that out there and seeing who hits them, but I guess this one needs some explaining.

To cool this particular engine, Kawasaki uses a rather large heat exchanger mounted somewhat aft of it, which would of course need to be removed for a bike install, and therein lies the problem. The two-thirds of that heat exchanger that's not being used to cool the engine is being used to cool the intake charge. That massive air-to-water intercooler is how this thing supports 300 hp. Without a lake to cycle through that intercooler, you have to find another way to cool the intake charge. An air-to-air unit won't get the job done (or at least not one the size you can fit on a bike... remember, you can't block the radiator, which will also need to be a beast) unless you supplement it with methanol injection, which is a whole 'nother can of worms. Look at the intake cooling on a legit 300hp, sub-2.0L turbo street car, imagine stuffing that into a motorcycle chassis, and you'll get an idea of what I'm on about.

That's not to say you can't do it. It's just a huge pain in the ass, and by the time you get it running right, you could have put less time, money, and energy into setting up a turbo on a proper bike engine.

To be fair, the drivetrain isn't cake either. The trans and clutch can always come in the form of an H-D big twin unit- same as any "but it doesn't have a trans" swap- but getting a sprocket on the threaded output from the crank means machine work. Actually, getting a sprocket on the crank requires next to nothing. Getting it to stay attached requires splines. You probably also have to ditch the generator and run a separate alternator from the blower drive, which means timing has to come off the sprocket... you get the idea. It's a series of problems that are solvable individually but collectively represent more work than the project is worth.

I pointed to the cooling issues because they're really the novel problem with this swap. With any engine swap, the first problem is getting it to physically fit into a chassis, and the second is getting it hooked to a transmission that powers a wheel. The third real problem is replacing, re-routing, and re-wiring all of the engine's systems that had to be left behind, and that's where this particular swap proves to be unusually difficult. Really, there are a litany of reasons it doesn't make sense, starting with the fact that a running, not-blown-up 300LX motor is worth too much to use in a project as inherently hillbilly as stuffing a Jet Ski motor in a bike chassis anyway.

(I may have spent some time behind a parts counter in a Kawi shop staring at these things and considering doing exactly what we're talking about.)
 
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