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Old 08-21-2009, 12:35 PM   #18 (permalink)
JacobAziza
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Join Date: Mar 2009
Location: Oakland, CA
Posts: 397

Big Orange Work Truck - '83 Ford F-250
90 day: 27.54 mpg (US)

Jessica's - '04 Toyota Matrix
90 day: 41.21 mpg (US)

Ninjette - '01 Kawasaki Ninja EX250R
Thanks: 44
Thanked 68 Times in 45 Posts
Quote:
Originally Posted by tasdrouille View Post

Assumptions/approximations:

- The idling engine requires 2 hp
- Steady state at 1800 rpm requires 15 hp
(I'm assuming that is a diesel specific BSFC map?)

Why idle? EOC requires 0hp

What did you base the numbers 15hp for steady state and 45hp for accelerating from 45mph to 67mph on?

Steady state should depend on the Coefficient of drag,
Acceleration should depend on both the weight of the vehicle and the rate of acceleration.

In a motorcycle, very low weight and high CoD, it would take less hp to accelerate relative to steady state; in theory the benefit would be more pronounced. On the other hand, my truck is much more aerodynamic than my EX250 bike, and weighs 11 times as much, so lower power needed for steady state and higher to accelerate. If your numbers were for a car, considering how close they ended up, it still seeming like I shouldn't expect to see any benefit.
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Quote:
Originally Posted by Piwoslaw View Post
A few months ago I returned home just as my neighbor pulled into his driveway. It was cold (around freezing) with some rain and sleet, and he yells to me: You rode your bike? In this weather?!?

So the other day we both returned home at the same time again, only now the weather is warm, sunny, with no wind. And I yell to him: You took the car? In this weather?!?
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