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Discussion Starter #1
I wrote a simple webpage to try to compute the performance of the bike based on published dyno figures supplied by BMW (for the K1600GT and K1300GT) or third-party rear-wheel dynos for other bikes. Since the latter factors in drivetrain loss, there's some inaccuracy in comparing them to the BMWs, but it's still useful.

http://cycle-ergo.com/Dyno.html

To use it, just click the button for the motorcycle you want. By default it graphs acceleration versus speed but you can choose to view it vs RPM instead. It also estimates acceleration times from 20 mph to whatever, including to top speed. Each necessary upshift adds a penalty of a half-second by default, which you can change.

I start at 20 mph because dynos only start at 2000-2500 RPM usually, and never zero obviously.

Air resistance is taken into account. I do this by using the true (unrestricted) top speed of the bike to know when air resistance exactly equals forward thrust, from which I can compute the air resistance at any speed.

By the way I used 740 lbs as the weight figure for the K1600GT because that's probably what it weighs with side bags. Rider weight is currently hard-coded at 160 lbs but I'll make it an input field later.

The verdict is that the K1600GT should be very fast in the low gears up until 80 mph or so, at which point the K1300GT pulls ahead. The Goldwing is ridiculously slow compared to everything else and the S1000RR is really fast.
 

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Where did the 1600 GTL go ? :)
Could you please put in, as a useful reference for many of us, also figures for r1200rt (DOHC engine - current) and k1200lt ?
 

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Discussion Starter #3
I'll add the R1200RT and K1200LT tonight, but I removed the GTL because its top speed is restricted so the data technically wouldn't be accurate for it (or it'll be almost identical to the GT until 137 or whatever, at which point everything goes to zero). Also its weight is only 26 lbs heavier so it's basically redundant.
 

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CGameProgrammer said:
The verdict is that the K1600GT should be very fast in the low gears up until 80 mph or so, at which point the K1300GT pulls ahead. The Goldwing is ridiculously slow compared to everything else and the S1000RR is really fast.
I love the 1000RR reference!

Does this kind of match what the early reviewers mentioned? I thought I saw where they thought the 13GT was faster across the board (primarily because of weight)
 

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Thank you for the additions. I really hope you can find something for the RT. One observation though : changing the rider weight doesn't change anything in the performance data ... probably you're still working on it.
 
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