kk watts

No math wizardry involved, but here you go. (change file extension to .xls after saving)

frenchyge said:

No math wizardry involved, but here you go. (change file extension to .xls after saving)

I've noted that the formula
P = (5.244820) * S + (0.01968) * S3
referenced on kurtkinetic.compowercurve.phpOpen ↗
and
kurtkinetic.comcalibration chart.phpOpen ↗

does *not* agree with the table numbers in the PDF link on the top
of kurtkinetic.compowercurve.phpOpen ↗.

In the PDF, for example, 22 MPH == 319.483,
but the formula gives 324.9387

I believe the right formula (if you believe the PDF) is:
P = (5.244820) * S + (0.0191676) * S3

This agrees with the PDF, and is mentioned on the bottom of the page of
kurtkinetic.comhistory fluid machine.phpOpen ↗
e.g.:
[5.24482 x (Ave. Speed in MPH)] + [0.0191676 x (Ave. Speed in MPH)³]=

So, if anybody cares, somebody should contact Kurt and say -
look - you've posted one equation on:
kurtkinetic.compowercurve.phpOpen ↗
kurtkinetic.comcalibration chart.phpOpen ↗

and another on
kurtkinetic.comhistory fluid machine.phpOpen ↗
and in their PDF table of wattages...

What is the real eqn?

For now, go with the conservative one using the 0191676 factor, which
will wipe off about 5 to 10 watts from the other formula for those of us avg'ing 300-350 watts...

In any case, I've powertapped the Kinetic, and find it to be in the ballpark, but still a rough approximation to actual power being produced
(see groups.google.comaab146429d79d753Open ↗
)

dave linenberg

tdl123321 said:

Just wondering if any of you math wizards have plugged the kk power curve into the computer to get a spread sheet of x speed= watts.

P = (5.244820) * S + (0.01968) * S3

As has been discussed recently, there can be accuracy issues with these kind of calculations, though the KK trainer appears to be one of the better ones.

If you're interested, I have a webpage that can make charts for any of the trainers that KK tested. It can also do the calculations to a Polar or iBike ride file, adding in the missing power info. The page is at:

http://curveship.dyndns.org/trainerpower

-- Adam

ahaile said:

As has been discussed recently, there can be accuracy issues with these kind of calculations, though the KK trainer appears to be one of the better ones.

If you're interested, I have a webpage that can make charts for any of the trainers that KK tested. It can also do the calculations to a Polar or iBike ride file, adding in the missing power info. The page is at:

curveship.dyndns.orgtrainerpowerOpen ↗

-- Adam

Thanks for the link. That is a pretty cool page. The customized zones are a nice touch.

tdl123321 said:

Thanks for the link. That is a pretty cool page. The customized zones are a nice touch.

Glad you liked it. I just put it up a couple of days ago. If you hit any bugs or have any suggestions, let me know.

dlinenbe said:

I've noted that the formula
P = (5.244820) * S + (0.01968) * S3
referenced on kurtkinetic.compowercurve.phpOpen ↗
and
kurtkinetic.comcalibration chart.phpOpen ↗

does *not* agree with the table numbers in the PDF link on the top
of kurtkinetic.compowercurve.phpOpen ↗.

In the PDF, for example, 22 MPH == 319.483,
but the formula gives 324.9387

I believe the right formula (if you believe the PDF) is:
P = (5.244820) * S + (0.0191676) * S3

This agrees with the PDF, and is mentioned on the bottom of the page of
kurtkinetic.comhistory fluid machine.phpOpen ↗
e.g.:
[5.24482 x (Ave. Speed in MPH)] + [0.0191676 x (Ave. Speed in MPH)³]=

So, if anybody cares, somebody should contact Kurt and say -
look - you've posted one equation on:
kurtkinetic.compowercurve.phpOpen ↗
kurtkinetic.comcalibration chart.phpOpen ↗

and another on
kurtkinetic.comhistory fluid machine.phpOpen ↗
and in their PDF table of wattages...

What is the real eqn?

For now, go with the conservative one using the 0191676 factor, which
will wipe off about 5 to 10 watts from the other formula for those of us avg'ing 300-350 watts...

In any case, I've powertapped the Kinetic, and find it to be in the ballpark, but still a rough approximation to actual power being produced
(see groups.google.comaab146429d79d753Open ↗
)

dave linenberg

Hi everyone, a new poster here.
Actually, I contacted Kurt Kinetic about this very issue in December and so far they seem to have ignored it. Yes, the 0.0191676 (0.01917) figure is the accurate one. That's what is plugged in to their power calculator as a default "B" value.