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Discussion Starter #1
today i took the sp1 out for a spin and i'm suprised at the speedo readings
i can easily be doing an indicated 100mph and it feel like 60 mph, friday i took my buell 1125r out and while it may accelerate harder at 90mph i'm getting buffeted which i don't get on the sp1
are the sp1 aerodynamics that superior to the buell?
what should the stock sprocket sizes be? could that give me a different speedo reading?
 

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The stock sprocket sizes are 16/40 and it definitely feels different if you change them.

If you have a 15 at the front and/or a 43/42 at the rear, then the feeling you get is quite right.

All you need is a speedohealer so that your dash reading reflect the speed you're feeling riding at.
 

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Discussion Starter #4
just had a quick look and the rear sprocket is a 40t so i'm guessing without looking at the front its running stock
maybe honda's 2001 aero's are far superior to 2008 buells:)
 

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There are still a lot of things on the RC far superior than just about any Buell, aeros is just one of them.
 

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Yes

maybe honda's 2001 aero's are far superior to 2008 buells:)
Yes they are. Buells are meant to cruise and corner with a top speed of what 130. RC with racing aero and a top speed of 170.

I commute on a '08 xb12r and with the stock windscreen @ 70 mph I had to pull myself forward with the wind blowing right on my face shoulders. It's a workout.

I've since put a double bubble on her and it is much nicer. I still get wind on my helmet but I'm not straining my neck. and can now ride with one hand up to around 85-90 instead of 65-70 with the stock screen.
I can cruise at 100 on the rc with one hand on the bars and my 04 r1 was the same as the rc
 

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What do you think of this?
My theory; which could be proven or dis-proven with a little mathmatics.

190/50 tire with 15/40 sprockets is equal to 190/55 tire with 15/42 sprockets in terms of final gearing.

Am i thinking right?
 

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What do you think of this?
My theory; which could be proven or dis-proven with a little mathmatics.

190/50 tire with 15/40 sprockets is equal to 190/55 tire with 15/42 sprockets in terms of final gearing.

Am i thinking right?
Nah

You only have about a 3% difference going from 50 to a 55 tire which is
It's equivalent to a -1 or -2 rear sprocket change
Going from 16/40 to 15/42 is a 12% change
 

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Nah

You only have about a 3% difference going from 50 to a 55 tire which is
It's equivalent to a -1 or -2 rear sprocket change
Going from 16/40 to 15/42 is a 12% change
Take 16 out of this conversation. We're only talking about the rear sprocket and tire. Given a 15 up front.
Ok, so a 190/55 will only travel 3% farther than a 190/50? That doesn't sound right...
What's the difference in percentage going from 40 to 42? All other things the same.
 

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Take 16 out of this conversation. We're only talking about the rear sprocket and tire. Given a 15 up front.
Ok, so a 190/55 will only travel 3% farther than a 190/50? That doesn't sound right...
What's the difference in percentage going from 40 to 42? All other things the same.
15/40 is 6.67% lower then stock
15/42 is 12% lower
So about 5.5% difference
A tire change being 3% it would be close.

I'm using this calculator http://www.gearingcommander.com/
 
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