Formula USA Sportbike class

[wvracer97]

Based on the mailer the HP limit for this class is 105.  In the 2005 rulebook it states 115.  Anyone know which one is correct?  Thanks!

Also, does our CCS# carry over to FUSA #'s??

[BRG]

Scott,
In 2004 the limit was 115. I think the 105 is a misprint, most of the bikes stock are at that or over.

Brian

[Eric Kelcher]

2005 rule book is not released yet  ::)

In 2004 it was 100 but the printed rulebook came out before the change from Dynojet to Factory and so it showed 115 hp but competitor update reflected the change from 140 for Formula Sportbike to 122 and Sportbike from 115 to 100 and Thunderbike from 3.8 to 4.0  (4.5 for 4 cylinders???

2005 will be 105 per the mailer for Sportbike

[Eric Kelcher]

Also, does our CCS# carry over to FUSA #'s??

No FUSA numbers are issued to one competitor for the country, CCS numbers are issued per region. You can try to get the same number both FUSA and CCS.

[wvracer97]

Thanks for the info!  So, if my 600cc Honda dynos at or below 105 at the rear wheel I'll be OK??

[motomadness]

Get it done a Factory (eddy current) dyno, not a Dynojet (sweep) dyno.  I think the Dynojet 2500 series are eddy current and may produce numbers similar to the Factory.  I think last year at Daytona, the FUSA techs stated that there was about a 13% difference between the sweep and the eddy current dynos.

Here's the idea
sweep => tune to 115 hp and you might be okay on the eddy current
eddy current => tune to 105 hp and you might be okay on the FUSA dyno
tune on the FUSA dyno => you'll be spot on.

[Eric Kelcher]

The Factory test  done at FUSA is also a sweep test.

the difference is the correction facotrs and what measures the HP. Dyno jet uses a preset weight drum and how fast that spins up to determine hp (on model 150 which is what was used 2000-2003) on the Factory it uses a load cell to determine how much energy the bike is putting to the ground (I guess that is the eddy current part) but the major differnce is the correction factors used best I can understand is Dynojet makes corrections to try to make RWHP indicate what the crank hp is by figuring the parasitic losses of transmission chain etc. Factory measures the actual rear wheel Hp with only correction being for temp/hum/baromtric pressure.

But the 13-15% additional hp on dynjet is a good indication of what you will see on a factory dyno. But word is that a factory dyno has less variation from one dyno to another whereas dynojet can vary 5% and seems to be more temp/humdity/etc affected.

[xseal]

So does that mean a stock 600 w/ a pipe is likely to be over the limit or under?

Same for a new GSXR750, will a built SS engine be over 122hp on the FUSA dyno?

[motomadness]

So does that mean a stock 600 w/ a pipe is likely to be over the limit or under?

Same for a new GSXR750, will a built SS engine be over 122hp on the FUSA dyno?

I don't think so.  I got blitzed at Road America by some pretty fast bikes and my 2000 R6 had a recorded 107 hp on a Dynojet dyno.  

[motomadness]

The Factory test  done at FUSA is also a sweep test.

the difference is the correction facotrs and what measures the HP. Dyno jet uses a preset weight drum and how fast that spins up to determine hp (on model 150 which is what was used 2000-2003) on the Factory it uses a load cell to determine how much energy the bike is putting to the ground (I guess that is the eddy current part) but the major differnce is the correction factors used best I can understand is Dynojet makes corrections to try to make RWHP indicate what the crank hp is by figuring the parasitic losses of transmission chain etc. Factory measures the actual rear wheel Hp with only correction being for temp/hum/baromtric pressure.

But the 13-15% additional hp on dynjet is a good indication of what you will see on a factory dyno. But word is that a factory dyno has less variation from one dyno to another whereas dynojet can vary 5% and seems to be more temp/humdity/etc affected.

The point I was trying to make was that the technology was the main difference for the change in hp figures.  The Dynojet 150 can only do sweep tests, whereas the Factory made to do sweep test, where it is much more capable dyno system.  

At Daytona, a special meeting was held where they mentioned that they tried to do steady-state test on the Factory dyno, but because of potential cooling concerns of the Buells, that option was removed and they stuck with the sweep test and the change in limits.

Key thing is to check what kind of dyno you are measuring your bike's power on.  A Dynojet 2500 maybe closer in line to the Factory because of similar technology.  As far as variation from system to system, that's a whole nother ball of wax.

[Eric Kelcher]

FYI 2005 rulebook