Corrected and US 1/4 mile times

Corrected and US 1/4 mile times

Author
Discussion

alfa daley

Original Poster:

915 posts

248 months

Friday 3rd November 2006
quotequote all
I have noticed in a lot of American websites and bike magazines they always claim 1/4 mile times that are almost always faster than UK or European magazines for identical bikes. What's the deal? Do their drag strips run slighly downhill or something? Perhaps a US 1/4 mile is less than a European one??

This review is an example, just what is a corrected 1/4 mile surely you either did the 1/4 in that time or you didn't.

11.5 1/4 on a standard Hornet 600, I dont think so!

www.motorcyclistonline.com/roadtests/middleweight_motorcycle_comparison/

Time Machine

487 posts

262 months

Friday 3rd November 2006
quotequote all
I can only guess that they are trying to correct for air quality and so 'correcting' to sea level at standard atmospheric pressure.

As far as I am concerned a quarter mile time is what it says on the ticket, everything else is just conjecture.

p15ton

495 posts

250 months

Friday 3rd November 2006
quotequote all
I believe they are corrected for altitude.

protemporum

68 posts

224 months

Friday 3rd November 2006
quotequote all
A lot of 'Road Test' motorcycles supplied for testing to american publications have been 'Blueprinted' to give maximum performance. When Bridgestone was a bike manufacturer, they were notorious for 'tuning' the barrel ports with a rotory file. It became so bad, that bikes were stripped to show the public what mods had been done! Also U.S. spec bikes sometimes have different gearing.

JenkinsComp

918 posts

261 months

Monday 6th November 2006
quotequote all
Alot of drag strips in the US are at fairly high altitude, where air is less dense and therefore combustion engines produces less power than at sea level.

For instance, LA County Raceway is 2710 ft above sea level and 1/4 mile times are multiplied by 0.97 or 97% to correct for altitude. MPH is multiplied by 1.03 or 103%.

BennettRacing

729 posts

225 months

Monday 6th November 2006
quotequote all
JenkinsComp said:
Alot of drag strips in the US are at fairly high altitude, where air is less dense and therefore combustion engines produces less power than at sea level.

For instance, LA County Raceway is 2710 ft above sea level and 1/4 mile times are multiplied by 0.97 or 97% to correct for altitude. MPH is multiplied by 1.03 or 103%.


so if we run a 7;16 in 3900ft

what would that be corrected? is there a formula?

Time Machine

487 posts

262 months

Monday 6th November 2006
quotequote all
BennettRacing said:
JenkinsComp said:
Alot of drag strips in the US are at fairly high altitude, where air is less dense and therefore combustion engines produces less power than at sea level.

For instance, LA County Raceway is 2710 ft above sea level and 1/4 mile times are multiplied by 0.97 or 97% to correct for altitude. MPH is multiplied by 1.03 or 103%.


so if we run a 7;16 in 3900ft

what would that be corrected? is there a formula?


Working on the basis that 0=1.00 and 2710=0.97 and assuming a linear interpolation (which may well be wrong) I would say 3900ft is 95.68%, which converts your 7.16 to 6.85

Which sounds like bunk to me. Of course with a blown car you can just turn the blower faster and negate some of the effects of poor air.

The only way you could get accurate figures for this would be to keep every variable except for relative altitude the same and generate a sufficiently large data set.


Edited by Time Machine on Monday 6th November 16:16