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Discussion Starter · #1 ·
I've never thought there was a great deal of value in the engine output figures against dry weight of bikes. An approach that shows easily related values (for me anyway) is to add a realistic load mass (pilot, gear and standard bike additions) to the dry weight and then divide it by either the power (kw) or torque (kg-m). I never know these days what hp is being quoted bhp, hp or ps so Kw is the standard for me.

eg KS (dry) + pilot and gear:

Working Kg / Kw = (226.5kg + 110kg) / 123kw = 2.74
Working Kg / TQ = (226.5kg + 110kg) / 13.3kg-m = 25.3

While I'm open to different interpretations this is what the results broadly mean to me:

(1) The lower the final ratio the better the performance.

(2) KG/TQ is a measure of accelleration

(3) KG/KW is a measure of top end

It doesn't take a lot of change in torque, power and working kg to affect some "accepted" performance ratings. If Staintune's figures for Kw and Kg changes are accurate then the KS and particularly the KR rate very well against the Busa and most high performance bikes. Shaft drive losses are an unknown factor but if you do the math and comparisions you will at least get an idea of straight line performance.

Cheers
Lenz
 

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<< If Staintune's figures for Kw and Kg changes are accurate then the KS and particularly the KR rate very well against the Busa >>

Umm, don't get too carried away. My S is OUTSTANDING, but it's no Busa killer in acceleration or top speed. The S, however, WILL trounce the Busa in every other area, e.g., brakes, suspension, chassis. That's from my experience owning 3 Busas.
 

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Lenz said:
I've never thought there was a great deal of value in the engine output figures against dry weight of bikes. An approach that shows easily related values (for me anyway) is to add a realistic load mass (pilot, gear and standard bike additions) to the dry weight and then divide it by either the power (kw) or torque (kg-m). I never know these days what hp is being quoted bhp, hp or ps so Kw is the standard for me.

eg KS (dry) + pilot and gear:

Working Kg / Kw = (226.5kg + 110kg) / 123kw = 2.74
Working Kg / TQ = (226.5kg + 110kg) / 13.3kg-m = 25.3

While I'm open to different interpretations this is what the results broadly mean to me:

(1) The lower the final ratio the better the performance.

(2) KG/TQ is a measure of accelleration

(3) KG/KW is a measure of top end

It doesn't take a lot of change in torque, power and working kg to affect some "accepted" performance ratings. If Staintune's figures for Kw and Kg changes are accurate then the KS and particularly the KR rate very well against the Busa and most high performance bikes. Shaft drive losses are an unknown factor but if you do the math and comparisions you will at least get an idea of straight line performance.

Cheers
Lenz
The aerodynamic factor are much more important for "top end" than KG/KW.

/Michael
 

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Discussion Starter · #4 ·
ratemut said:
The aerodynamic factor are much more important for "top end" than KG/KW.

/Michael
Agreed there are a lot of unknowns in the mix and between shaft drive losses and high speed aerodynamic losses we still aren't getting direct comparisions. Just playing with the figures and supplied data suggests a loss of even 10kg and a gain of 5 - 10kw has significant performance effects. Just for interest sake I wonder how much weight loss and power gain is possible using the AC Schnitzer headers and muffler. Less mass in the wheels could also be good for both performance and handling, hopefully not at the expence of wheel strength or durability over standard.

Anyone got any info on AC Schnitzer results.

Cheers
Lenz
 
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