200 mph fj?

[andyb]

  150mph should be relatively easy, though harder than you'd expect. 

I used to see an **indicated** 153-154mph on my '85 wid open running across GA at 5:00am. There may have been another mile an or two an hour in there with wringing the twist grip a bit more, and tucking in a bit tighter...

Now, I know the clocks are optimistic but I have since figured i was actually traveling perhaps 145mph, on a bone stock FJ with F1R slip-ons as the only 'performance' mod. An actual 150mph would not be all that tough/ expensive, -seems to me.

Last point here, my '02 GSX-R 750 is written to be able to hit an actual ~165mph -although I bought this after having kids so this is in fact the first machine I have owned without having been within spitting distance of its top end.

Dan

Yes dan, and was this in a standing mile, or over a longer distance?  There's a reason why I said it'd be harder than you think.    Of course, that's also what the typical Hayabusa owner says, after endless nonesense that their bikes will go 200mph stock on the speedo, it turns out that they're a comfortable 40hp short, and even then there's some riding ability required.

My ZX9 is geared down from stock and yet can put 180mph on the speedo when the stockers only could manage 170 on radar, so it must be a super fast version, right?  Or realistically I'm lucky to be breaking 150 with it....

[Bill_Rockoff]

Early FJs, with their narrower uppers, were supposedly passing redline in 5th (150-ish) stock.  Later larger bikes were apparently hitting redline (high-140s) and the taller windscreen rubber-mounted late-model ones were still surpassing their power peak (8,500-ish rpm) in top gear, high 130's / low 140's.

These bikes seem to be a bit above 100 rwhp stock (mine showed 103 on a DynoJet and would fetch up against 9,500 rpm in top gear back then.)

So, depending on which year FJ we're talking about, it seems reasonable to say "100 rear-wheel hp will get you to about 150 mph, properly geared."

Power rises with the cube of speed (going two times as fast needs two-cubed the amount of power) so to make a 150 vehicle go 200 mph, you'd need (200/150)^3 the horsepower.   For an FJ, that's about 237 rwhp. 

With built normally-aspirated FJ motors reaching close to 160 at the wheels, I imagine it's pretty close to possible with a basic low-boost turbo (~5psi) and might even be possible without intercooling, at least for a short run (dyno, Maxton mile, etc.)  There used to be a Mister Turbo setup for the FJ, but I think it used a single Lectron carb.

To try to mimic a Turbo Hayabusa's reliability and rideability, though, I think we'd want to do intercooling and possibly a computer-controlled fuel injection system to get rid of the plumbing nightmare that would be a blow-through carb, or the tuning nightmare that would be a draw-through.

[fintip]