Truth in dyno
Road Captain
Joined: Jan 2007
Posts: 605
Likes: 1
From: Minnesota
Good comment on the dyno differences iclick.
Harleytuner, I was told by my tuner that the SuperFlow WinDyn results were appoximately 10% lower than would be measured on the DynoJet system. They provided a chart with my HP readout that shows the WinDyn number (81.6), STTP (77.1) and the SuperFlow SAE numbers (74.1). Also, my numbers for TQ and HP are consistent with others and Jamie's data WHEN "corrected" from the SuperFlow number to the DynoJet using 10%.
I also researched this on Google and pretty much across the board they confirm the differences between the two to be 10-15% based on the technique used to measure HP and TQ.
So what do I really have?
Harleytuner, I was told by my tuner that the SuperFlow WinDyn results were appoximately 10% lower than would be measured on the DynoJet system. They provided a chart with my HP readout that shows the WinDyn number (81.6), STTP (77.1) and the SuperFlow SAE numbers (74.1). Also, my numbers for TQ and HP are consistent with others and Jamie's data WHEN "corrected" from the SuperFlow number to the DynoJet using 10%.
I also researched this on Google and pretty much across the board they confirm the differences between the two to be 10-15% based on the technique used to measure HP and TQ.
So what do I really have?
Grand HDF Member
Joined: Mar 2007
Posts: 4,923
Likes: 266
From: Deep in the heart of New Jersey
I got a couple questions for someone who might know. 1st, how much difference does tire air pressure make during a dyno?. Would the end numbers be higher or lower?. 2nd, I have seen this guy Dr. Dyno who uses a trailor mounted dyno unit. How accurate do you think a unit that is trailered and bounced around the country can be? I've seen him tune a few bikes so he know his stuff, just wonder how sensitive the inards are.,,
Road Captain
Joined: Aug 2008
Posts: 716
Likes: 10
From: Shreveport,La
Ok so here is something I have wondered for a long time. You go to these rallies and see the guy with the Dyno setup in the parking lot. He does a Dyno pull on a bike comes out with a printed sheet showing what he bike is doing and says I can make it better. 15 minutes later he does another Dyno pull and comes out with a better sheet and better numbers. Now my question is, can he by throttle play change the numbers on a Dyno pull to make it better or worse? Can he trick the owner in thinking he helped the bike by how he uses the throttle during the Dyno pull I guess is what I am asking?
I got a couple questions for someone who might know. 1st, how much difference does tire air pressure make during a dyno?. Would the end numbers be higher or lower?. 2nd, I have seen this guy Dr. Dyno who uses a trailor mounted dyno unit. How accurate do you think a unit that is trailered and bounced around the country can be? I've seen him tune a few bikes so he know his stuff, just wonder how sensitive the inards are.,,
Ok so here is something I have wondered for a long time. You go to these rallies and see the guy with the Dyno setup in the parking lot. He does a Dyno pull on a bike comes out with a printed sheet showing what he bike is doing and says I can make it better. 15 minutes later he does another Dyno pull and comes out with a better sheet and better numbers. Now my question is, can he by throttle play change the numbers on a Dyno pull to make it better or worse? Can he trick the owner in thinking he helped the bike by how he uses the throttle during the Dyno pull I guess is what I am asking?
Road Master
Joined: Mar 2009
Posts: 795
Likes: 1
From: Richmond, VA
Got a question then harlytuner. I called fuelmoto cause i was running a little rich at idle and my throttle position was at 0 but i was idling a little low. They said my whole map would be off if i didn't get the low idle taken care of. I can kind of understand if all of the measurements are based off of the throttle position. esp. if idle is supposed to be around 1k and im idling around 750. I have a 01 electraglide with the magget mirreli fuel injection. What do you think?
Good comment on the dyno differences iclick.
Harleytuner, I was told by my tuner that the SuperFlow WinDyn results were appoximately 10% lower than would be measured on the DynoJet system. They provided a chart with my HP readout that shows the WinDyn number (81.6), STTP (77.1) and the SuperFlow SAE numbers (74.1). Also, my numbers for TQ and HP are consistent with others and Jamie's data WHEN "corrected" from the SuperFlow number to the DynoJet using 10%.
I also researched this on Google and pretty much across the board they confirm the differences between the two to be 10-15% based on the technique used to measure HP and TQ.
So what do I really have?
Harleytuner, I was told by my tuner that the SuperFlow WinDyn results were appoximately 10% lower than would be measured on the DynoJet system. They provided a chart with my HP readout that shows the WinDyn number (81.6), STTP (77.1) and the SuperFlow SAE numbers (74.1). Also, my numbers for TQ and HP are consistent with others and Jamie's data WHEN "corrected" from the SuperFlow number to the DynoJet using 10%.
I also researched this on Google and pretty much across the board they confirm the differences between the two to be 10-15% based on the technique used to measure HP and TQ.
So what do I really have?
I called fuelmoto cause i was running a little rich at idle and my throttle position was at 0 but i was idling a little low. They said my whole map would be off if i didn't get the low idle taken care of. I can kind of understand if all of the measurements are based off of the throttle position. esp. if idle is supposed to be around 1k and im idling around 750. I have a 01 electraglide with the magget mirreli fuel injection. What do you think?
__________________
Jamie Long / Fuel Moto USA
The USA's Leader V-Twin EFI & Performance www.fuelmotousa.com
Contact 920-423-3309
Email jamie@fuelmotousa.com
Jamie Long / Fuel Moto USA
The USA's Leader V-Twin EFI & Performance www.fuelmotousa.com
Contact 920-423-3309
Email jamie@fuelmotousa.com
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I got a couple questions for someone who might know. 1st, how much difference does tire air pressure make during a dyno?. Would the end numbers be higher or lower?. 2nd, I have seen this guy Dr. Dyno who uses a trailor mounted dyno unit. How accurate do you think a unit that is trailered and bounced around the country can be? I've seen him tune a few bikes so he know his stuff, just wonder how sensitive the inards are.,,
