pounds and horsepower

Started by tzracer, February 28, 2006, 11:17:59 AM

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GrecianFormula40

Brian,
I'm asking this question for Timmay 'cause he's afraid to-
How about the inverse? What is the effect of mASS on deceleration?  ;D
CCS EX GP #181

tstruyk

QuoteBrian,
I'm asking this question for Timmay 'cause he's afraid to-
How about the inverse? What is the effect of mASS on deceleration?  ;D

shut-yo-mouf old man... you stay outta this!!!  I'ma gonna decelerate my mass below my ankle in yer depends covered arse!!!   ;D

you see randy, afraid to continue losing to the "bigger" man... had to go out and buy himself a ringer of a 750 (damn that thing is sweet).  you already had HP AND weight on me last year... you must be skeered of my new shiny white plates!   ;)  NOW i got stickers comin... you dont stand a chance!!

timmay!!!!


I better be nice if I'm gonna hitch a ride up north in april... when you headin to Hallet again Ray Ray??


CCS GP/ASRA  #85
2010 Sponsors: Lithium Motorsports, Probst Brothers Racing, Suspension Solutions, Pirelli, SBS, Vortex

"It is incredible what a rider filled with irrational desire can accomplish"

GrecianFormula40

You got a lot of room on the lower backside of those Taichis for all the decals and patches you want...more room than a I-70 billboard!  :D

Hallett on Sunday, and I'll be wearin my depends for sure, this thing scares me.

Hope you can make it to RA.
CCS EX GP #181

tstruyk

QuoteYou got a lot of room on the lower backside of those Taichis for all the decals and patches you want...more room than a I-70 billboard!  :D

Hallett on Sunday, and I'll be wearin my depends for sure, this thing scares me.

Hope you can make it to RA.


you sonofabitch.... haha

so I got a lil junk in the trunk... chics dig a round ass!  ;D

No dice for Hallett.. if it was in 2 weeks I might be able to make it fly, Road America I am 90% sure I am IN now!!!  Just need to make sure I get the new bike put together, i was not in a big hurry to get everything done at first, so I'll have to see how it goes.  If I have the shock and bodywork in that would be the minimum... things are looking pretty good after chattin with Rob last night!

timmay

oh and in conclusion... weight has an impact on the application of HP and torque... and noone really nows how or how much for sure but your best bet is stickers... sorry to jack the thread  ;)

CCS GP/ASRA  #85
2010 Sponsors: Lithium Motorsports, Probst Brothers Racing, Suspension Solutions, Pirelli, SBS, Vortex

"It is incredible what a rider filled with irrational desire can accomplish"

tzracer

QuoteBrian,
I'm asking this question for Timmay 'cause he's afraid to-
How about the inverse? What is the effect of mASS on deceleration?  ;D

Actually braking is also acceleration  :D
Brian McLaughlin
http://www.redflagfund.org
Donate at http://www.donate.redflagfund.org
 
2 strokes smoke, 4 strokes choke

lilroy

I like this stuff!!  Yes I am a geek.

So you've dispelled the myth that a given amount of weight loss on a low hp bike has a greater effect then on a higher hp bike.  I ran a few examples, and found that a given amount of wieght loss results in the same amount of increased hp avialable for acceleration, on a percentage basis, for a high hp bike as a low hp bike.

Just pointing this out so that all the lightwiehgt guys don't start getting fat.

Well I need to go, off shopping for a new pocket protector!! :D

HAWK

Brian I think I need an explaination of the horsepower determines acceleration theory. My understanding is that horsepower is a force X a distance over a time. This determines a terminal velocity (which by the way is more a function of drag than weight unless you are going uphill) As stated earlier the important factor in acceleration is torque.

First let's agree that horsepower cannot be changed by gearing. Feel free to correct me if I am wrong here.

Second let's agree that torque CAN be changed by gearing. Again correct me if I am mistaken.

Finally let's agree that ANY motorcycle accelerates better in 1st than it does in 5th.

In first gear the engines output, lets just grab a nice even number out of the air, 50 lbsft at 5000 RPM is converted by the transmission and sprocket ratio to 5000 lbsft at 50 rpm resulting in great acceleration but the engine exploding somewhere south of 50 mph (ok I guess by now you can tell I ride a twin, you modern inline guys substitute about 90 or so here). Now let's go to 5th gear and take that 50 lbsft at 5000 RPM and convert it to say 250 lbsft at 1000 RPM. Not nearly as much kick in the pants off the line but when your drag catches up with your ability to make horsepower (some amount of toque in some amount of time) you have a much better chance of being somewhere south of the point of engine explosion.

An interesting side note here is that peak horsepower is nearly always made at a higher RPM than peak torque. Reason being the relationship between speed and torque. As RPM increases the engine begins to have breathing problems and torque starts to fall off but since horspower is torque in time the higher RPM almost always overcompensates for falling torque for a little while.

I guess in conclusion there is no way to figure how many HP a pound is worth. However since getting them off the rider is more likely to reduce aerodynamic drag (read less girth through the air) that might be the most profitable in terms of top speed while getting them off the rotating mass makes the most sense for acceleration.
Paul Onley
CCS Midwest EX #413

steelcityracer

Im not sure about the actual hp to weight ratio, but as someone who has lost 45 lbs since I started racing, I can tell you from experience that losing weight will help you in all aspects of riding.  You will be able to brake later (less mass to slow down), corner faster (less mass trying to go straight), accelerate faster (again less mass to get moving), and you will  most likely have better technique and less fatigue.

steelcityracer

Losing wieght off the rider will have a better effect on cornering and braking than loosing it off the bike will, because by loosing weight off of the rider, you are effectively lowering the center of gravity, and increasing mass centralisation.

Nate R

Quoteran a few examples, and found that a given amount of wieght loss results in the same amount of increased hp avialable for acceleration, on a percentage basis, for a high hp bike as a low hp bike.

Please give examples. What I'm finding is conflicting with this statement, and I want to be sure I'm reading it correctly.
Nate Reik
MotoSliders, LLC
www.motosliders.com
Missing my SV :-(

Super Dave

QuoteIm not sure about the actual hp to weight ratio, but as someone who has lost 45 lbs since I started racing..

Did you bother changing spring rates?
Super Dave

steelcityracer

Once I lost the weight I got a new bike, and got the suspension done acording to my current weight.