Butt Dyno ( definitely Valkyrie related )

[specialdose]

      Been riding my Fast Black 98 Tourer sans the windshield and bags. Pretty as she is dressed I think naked is her most beautiful pose.
Here is the question. Is it just an illusion from your torso catching the wind ( since I have not ridden for many years without a windshield or fairing ) or does she accelerate harder with the windshield off ? Sure feels like she does.

[Bighead]

NO

[cookiedough]

I highly doubt that wind resitance makes that much of a difference in speed.  Probably just feeling the wind hitting your face all the time feels like you are goiing faster, an illusion?

[Bighead]

I basically said the same in one two letter word

[signart]

Wind resistance makes a huge effect on speed. Which ever is less, with or without, will result in more performance. Size, shape, height, angle and flexibility or lack of flexibility of the screen, all have bearing on the resistance. Same goes for the rider plus what you are wearing, stance and helmet selection etc. A rider could potentially create more resistance than a screen. More resistance, less speed and mileage. Less resistance, better performance. You could be experiencing a boost in acceleration as the Tourer screen IMO would rate higher in resistance in comparison to other screens I have experienced.

[Fla. Jim]

It definitely makes a difference.  Go out and top her out with and without said screen and report back. My tourer  sans windshield and bags is 10 mph faster top end if memory  serves.

[Bighead]

It may make a minute diffrence but none that you could tell by the " Butt Dyno". I have ridden with and without the shield and the only difference is at the end of gone day when riding without it and your ass is whipped more than when you have it.

[The emperor has no clothes]

You don't many Memphis Shade windscreens at Isle of Mann. 

[Willow]

I ride my Standard without a screen and my Interstate with an eight inch screen.

Without a screen it will accelerate better (depending a bit on your body position) and will give you better fuel mileage.

It does cause you more fatigue at the end of a six hundred mile day. I have done a fifteen hundred mile day without the screen. The fatigue is not something that cannot be overcome.

[The emperor has no clothes]

I ride my Standard without a screen and my Interstate with an eight inch screen.

Without a screen it will accelerate better (depending a bit on your body position) and will give you better fuel mileage.

It does cause you more fatigue at the end of a six hundred mile day. I have done a fifteen hundred mile day without the screen. The fatigue is not something that cannot be overcome.

Damn ! Impressive. I'm getting tired just thinking about you riding 1500 miles in a day. Maybe Marines are tougher than Sailors. 

[specialdose]

       Jim at my age I don't have the sac to top her out. The ton mark is about my limit as I approach
 the 70 mark of life. I will take your word for it brother.

[Willow]

I ride my Standard without a screen and my Interstate with an eight inch screen.

Without a screen it will accelerate better (depending a bit on your body position) and will give you better fuel mileage.

It does cause you more fatigue at the end of a six hundred mile day. I have done a fifteen hundred mile day without the screen. The fatigue is not something that cannot be overcome.

Damn ! Impressive. I'm getting tired just thinking about you riding 1500 miles in a day. Maybe Marines are tougher than Sailors. 

LOL!  That's not the most.  That just happens to be the one with documented validation.   

[Rams]

It may make a minute diffrence but none that you could tell by the " Butt Dyno". I have ridden with and without the shield and the only difference is at the end of gone day when riding without it and your ass is whipped more than when you have it.

Would it not depend on the sensitivity of the "Butt Dyno" in both acceleration and whupped measuring?   

Being the Officially Recognized Pain In The Ass (ORPITA) I am, one could conclude that I have some expertise and recognize the slight differences in "Butt" Dynamics and Sensations.    I can state unequivocally that any ORPITA worthy of such a title must have the sensitivity/ability to understand just how far to push the PITA issues.   

One must also recognize that the time lapses between riding the "fat gurl" will also heighten the acceleration "experience".   One's "Butt Dyno" loses calibration with time and many times will provide an unexpected thrill (measured with a "Fun Meter") if the time elapsed is greater than manufacturer recommended time intervals.   It is without a doubt that when one asks the "fat gurl" to move her ass, she does accomplish that task in an expedient manner though.    As to the question of "Butt Dyno" reliability and accuracy though, YMMV.     

[MP]

I remember reading the first Valkyrie reviews when it came out.  They stated that removing the windscreen added about 10 mph to the top end.

Now, in normal acceleration to 60 or so, it will make very little difference.  Like cars and trucks, wind resistance is not much of a factor, until you get over 55 or 60 mph.  After that, it goes up VERY QUICKLY.

[TallRider]

I would think the windshield is more aerodynamic than your body unless you lean forward putting your head into the wind. Standing straight up would be more like an air brake without a windshield which has a deflective surface uposed to your body.?

[MP]

I would think the windshield is more aerodynamic than your body unless you lean forward putting your head into the wind. Standing straight up would be more like an air brake without a windshield which has a deflective surface uposed to your body.?

The top end speeds on the Valkyrie, and the slightly slower 1/4 miles times WITH the windscreen, say that the screen is LESS aerodynamic than the body.  The body is probably less aero, but the screen  is bigger, and there is still some body drag even with the screen.

[TallRider]

Probably correct. They say car is less  aerodynamic if the windows are down creating more drag. I personally feel no drag or pressure on my body but I suspect there could be turbulence causing some drag

[Bighead]

I ride my Standard without a screen and my Interstate with an eight inch screen.

Without a screen it will accelerate better (depending a bit on your body position) and will give you better fuel mileage.

It does cause you more fatigue at the end of a six hundred mile day. I have done a fifteen hundred mile day without the screen. The fatigue is not something that cannot be overcome.

Damn ! Impressive. I'm getting tired just thinking about you riding 1500 miles in a day. Maybe Marines are tougher than Sailors. 

I see Willow deleted my post and that is ok I just hope you got to read it before he did

[The emperor has no clothes]

I ride my Standard without a screen and my Interstate with an eight inch screen.

Without a screen it will accelerate better (depending a bit on your body position) and will give you better fuel mileage.

It does cause you more fatigue at the end of a six hundred mile day. I have done a fifteen hundred mile day without the screen. The fatigue is not something that cannot be overcome.

Damn ! Impressive. I'm getting tired just thinking about you riding 1500 miles in a day. Maybe Marines are tougher than Sailors. 

I see Willow deleted my post and that is ok I just hope you got to read it before he did

Nope, but if you feel the need to repeat it knock yourself out.

[Bighead]

Nope posted it once and that was enough........you know where this is going.