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IT's SUPERCHARGED! NOT TURBO!!!

It has been reported, depending on the source as turbo or supercharged. MCN said its supercharged and I believe them.
look at the exhaust headers. Unless the turbo charger is way back next to the rear shock and the intake in routed back to the engine from there, this bike can't be turbocharged!

And supercharging isn't a bad thing. Potential for wild numbers like 500hp may be limited, but on motorcycles where smooth progressive throttle is VITAL, the lag free and most importantly linear throttle behaviour of a supercharged engine hold great advantage over a turbocharged one. A supercharged engine behaves as if its larger than it is all the time. A turbocharged one has a transition zone between its "large engine" and "not large engine" behaviour. Contrary to what all the owners of turbo bikes might tell you, that transition zone is hell on precise control of the bike in corners. You can learn to ride around it, yes, you can do anything. but if we are talking about ideal solutions, a 250hp supercharged engine is a far more usable machine than a 320hp turbo charged one.

Also, it must be pointed out masterful tuning of boost and fuel flow (on each engine individually) involving a very powerful ECU can yield brilliant steady state (lots of power) and transitional behaviour (no lag and predictable, linear throttle response) out of a turbo engine. But throw emissions into the mix and you're screwed. At least the manufacturers are. Motorcycles make throttle response and lag control even more difficult by the lack of rotational inertia in the engine. On a car engine, even if the boost comes on with a bang, a heavy crank and heavy flywheel soften its blow. On a motorcycle engine, too much boost suddenly means too much acceleration suddenly. You really want that?

I also want to address another point. I have a ZX-12R, and while mine hasn't been dynoed, most stock 12s dyno around 160hp at the wheel plus or minus 3hp. While most people are looking to get even more, and too much is never enough, I also know that I can rarely ride the thing full throttle unless I start at low rpm in high gear. My point is that whats needed is not more power and more speed. What would be nice is a supercharged 600 like the R6, and then not for peak power but to fill out its low end and bottom end.

I love big bikes because they start building serious power at 4000rpm and go beserk at 8000. If a 600 could get to about 120peak hp at the wheel but with a fat full torque curve (from forced induction), so that its already making 60hp by 4500rpm, and 100 by 9000, that would be perfect.
 

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supercharger drag is an issue if you're after peak power

If a supercharger gives you 50 additional hp but its drag takes away 10 leaving you with only 40 net extra, where a turbo would give you net 60 extra, you may deem the turbo a better choice. But in my opinion, on a motorcycle, 40 hp and linear throttle is far more important than 60hp and irregular throttle behaviour.

If you think you can build a turbo bike that will yield meaningfully more rear wheel output than a supercharged bike without lag showing up and while maintaining a smooth progressive throttle, you're very mistaken.

The issue in not that there will be lag. Lag by itself is not bad. What is bad about motorcycle turbos is the throttle behaviour. If you're in a corner, leaned over and you get on the gas for the drive out, you don' want the bike giving you more than you want it to. On a turbo bike, you simply don't have such precise control on the engine response. Bikes like the gixxer1k and ZX-12R are already very unforgiving of throttle misapplication. turbocharging them will compound the problem manifold.

No, I remain convinced that turbochargers are ideal for straight line acceleration only. For an all round use motorcycle, a low boost turbo might be OK, but I'll take a supercharger instead. I am not a big fan of superchargers, and on a car, I'll take a turbo over a supercharger most days. but not on a bike.
 

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turbo is not like 2 stroke

in two strokes you merely have a very steeply climbing power band. On a high boost turbo bike, you have an engine whose off throttle to on throttle behaviour is not satisfactorily predictable and linear. its not about being peaky or not. Its about there being no time gap between when you ask the engine to do something and when it does it. Turbo bikes didn't take off (in sales, I mean) for a very good reason. And that reason is that a turbo bike needs its operator to ride around its imperfect engine response.

turbos are NOT an ideal solution on a motorcycle in tight corners.
 

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Re: Motorcycle Land Speed Record kind of talk

dimensionally, he is correct. power = force x velocity. rotational power = rotational force (torque) x rotational velocity (rpm).

drag is a force that is applied to the vehicle by the air, and at the point the vehicle stops accelerating due to drag, the force that it is applying on the air is equal and opposite to the drag. What force is being applied? that is the power being transmitted to the ground by the tyre(s) divided by the velocity of the vehicle.

where does torque come into it? The engine produces a certain amount of torque that is multiplied or reduced by the gearbox and the differential. At the end, you have a torque being applied to the hub. torque divided by the tyre diameter gives you the force being applied to the ground at the contact patch.

As long as you have some traction, the limit to your maximum speed with by the power output and gearing. meaning torque.
 
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