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[Billygiles]

trying this again

SAE  is at 2
dont know what this means but earlier reply said it should be at 5

[Midnight Rider]

Well...the SAE value at 2 explains SOME of it, and is also why the lines are so "wavy".  Still, all those numbers are highly suspect.  As mentioned, if the bike is running well, who cares?

But, I'll bet if you went to another dyno and just did a pull to see what the numbers are, they would not be anywhere near those.

[grc]

Look at that info in the top right corner and you will see the following:

CF:   SAE       Smoothing:    2

Those are two different things.  CF stands for correction factor, and the choices usually are None, STD, or SAE.  The correction factor is an attempt to "standardize" the results for various atmospheric conditions at the time of the test.  The preferred method is to use SAE, and it usually will result in slightly lower numbers than STD.  Smoothing is a number from 0 to 5 and it's a measure of the method used to extrapolate the curve between actual data points.  5 is the setting that results in the "smoothest" curve.  Using a lower number results in the jagged lines you see on your chart, and in my experience the only reason a dyno operator uses a lower number is to boost the peak numbers he can claim on that chart.  It may not make a huge difference, but it's not uncommon to see a two or three horsepower difference in peak output depending on the smoothing setting.

Jerry

[Midnight Rider]

Look at that info in the top right corner and you will see the following:

CF:   SAE       Smoothing:    2

Those are two different things.  CF stands for correction factor, and the choices usually are None, STD, or SAE.  The correction factor is an attempt to "standardize" the results for various atmospheric conditions at the time of the test.  The preferred method is to use SAE, and it usually will result in slightly lower numbers than STD.  Smoothing is a number from 0 to 5 and it's a measure of the method used to extrapolate the curve between actual data points.  5 is the setting that results in the "smoothest" curve.  Using a lower number results in the jagged lines you see on your chart, and in my experience the only reason a dyno operator uses a lower number is to boost the peak numbers he can claim on that chart.  It may not make a huge difference, but it's not uncommon to see a two or three horsepower difference in peak output depending on the smoothing setting.

Jerry

Much better explanation...

[funbiker1967]

So, I will bite.  How is it possible to pull these numbers with those upgrades?  I have done more and get way less.

[Billygiles]

Guys,
Factory specs say it should be at 122 torque so I don't know why anyone doubts 124.9
I have no idea what to say about the numbers, all I did was put in the tuner, v&h duals, street cannons and polished all ports for fuel. I didn't know what to expect even with stock parts much less with the little bit of work I did.
I do trust the service department at the dealership, they did say the the numbers were great and they had no Reason blowing smoke up my ass with inflated numbers because I wasn't looking for big numbers. I was told to have my scooter DYNOed after the mods I made.
With all the non-believers I will have it done again to verify what my bike is doing. If they are different I will certainly post
Dealer was Magic City HD. in Minot, ND

[grc]

Guys,
Factory specs say it should be at 122 torque so I don't know why anyone doubts 124.9
I have no idea what to say about the numbers, all I did was put in the tuner, v&h duals, street cannons and polished all ports for fuel. I didn't know what to expect even with stock parts much less with the little bit of work I did.
I do trust the service department at the dealership, they did say the the numbers were great and they had no Reason blowing smoke up my ass with inflated numbers because I wasn't looking for big numbers. I was told to have my scooter DYNOed after the mods I made.
With all the non-believers I will have it done again to verify what my bike is doing. If they are different I will certainly post
Dealer was Magic City HD. in Minot, ND

The claimed torque in the Harley spec sheet is measured at the crankshaft, not the rear wheel.  That makes a huge difference.  If you had had your bike checked at the rear wheel when it was stock you would have been lucky to see more than 100 lb-ft on an honest dyno.

People don't believe your numbers because your numbers are significantly in excess of what all others have reported with just pipes and a tune.  If you want to verify your numbers I'd suggest doing it on a different dyno, otherwise you won't know if it's just their "happy" dyno or if you've somehow found a magic performance combination.

Jerry

[hawgzilla]

The reason for the high numbers appears to me to be from erroneous barometric pressure readings.  Minot North Dakota is only about 1700 ft elevation but the pressure from the dyno run indicates 25" of mercury.  Unless there was a hurricane in the area that is a very unlikely pressure.  The correction factor is 1.19 which should indicate something is unusual with the conditions.
I also wonder why the tuner set it up to be so lean at wide open throttle.  Typical air fuel ratio at full throttle is more like 13:1 while yours is in excess of 14:1 for most of the run.  These are only runs #2 and #3 that were done 10 minutes apart.  Was it actually tuned?

[trahog]

Did you say you had it done at a Harley Dealer?,if so take it at a real Dyno guy.No way with pipes and a tuner.I've had 2 of these 110"s done buy the best tunner in the Business,98 hp and 114tq,after corrected,Happy dyno  the dealers have.IF it feels good don't worry about the Numbers.Have fun and ride it .and don't waste your money on doing another dyno to see the numbers.

[grc]

The reason for the high numbers appears to me to be from erroneous barometric pressure readings.  Minot North Dakota is only about 1700 ft elevation but the pressure from the dyno run indicates 25" of mercury.  Unless there was a hurricane in the area that is a very unlikely pressure.  The correction factor is 1.19 which should indicate something is unusual with the conditions.
I also wonder why the tuner set it up to be so lean at wide open throttle.  Typical air fuel ratio at full throttle is more like 13:1 while yours is in excess of 14:1 for most of the run.  These are only runs #2 and #3 that were done 10 minutes apart.  Was it actually tuned?

Yup, that's one way to either knowingly or unknowingly boost numbers, bogus temp and atmospheric pressure readings.  Sometimes it could be accidental, with a sensor just going bad and a rookie operator not noticing it.  Other times people attempting to boost business by inflating numbers do it on purpose.  That doesn't sound like the case here, but it's something to be aware of. If you remove the correction factor from the equation that 125 lb-ft becomes 105 lb-ft, btw.  BIG difference, and more in line with the reported mods and poor AFR control shown on the chart.  As you noted, it doesn't look like the bike has actually been tuned.

Jerry

[clubbie]

Must have been dyno'ed at 5500ft. Or the weather station is fu/cked. Or the old rest the intake probe on the exhaust trick (don't know if you can do that with the dynojets).

Anyway run it at the track and report back your mph, after all you can't race a dyno. (hint: MPH never lies)

[smiley1049]

Or if it feels good ride it it doesn't matter as long as your happy!

[HILLSIDECYCLE.COM]

The claimed torque in the Harley spec sheet is measured at the crankshaft, not the rear wheel.  That makes a huge difference.  If you had had your bike checked at the rear wheel when it was stock you would have been lucky to see more than 100 lb-ft on an honest dyno.

People don't believe your numbers because your numbers are significantly in excess of what all others have reported with just pipes and a tune.  If you want to verify your numbers I'd suggest doing it on a different dyno, otherwise you won't know if it's just their "happy" dyno or if you've somehow found a magic performance combination.

Jerry

Yes.
Difference between crankshaft numbers and the r/wheel are about 15-17%, due to the factors that stack up the parasitic loss thru the drive line.
Scott

[Billygiles]

Thanks for all the info. I learn from this forum all the time. I will have another dyno performed sometime in the future.
By the way I called the dealer and told the service mgr I was receiving comments that the numbers shown on their dyno were unobtainable with the mods made and he told me that 100-105hp 120-128 torque were very common and most scooter DYNOed out at those numbers.

Before you jump on the soapbox I want everyone to know I agree with the forum concerning the numbers.  I think a dyno tune up(on their dyno) in needed especially since he claim all the bikes they dyno come in at high numbers

Again, thanks to all those that provided feedback

[Midnight Rider]

Billy...there's one thing to keep in mind on this forum...well, actually there are several, but there are a LOT of very knowledgeable people on here who have been there/done that, some several times over.  No offense is ever intended...well, most of the time    But folks here will call a spade a spade, and most of us have seen results on "happy dynos" many times.  As a general rule...not dissing your dealer....HD dealerships rarely have dynos or people to operate them who know WTF they are doing.  I think if you did a poll here on the site, 8 out of 10 people would say that.  There are some really good tuners out there with honest dynos, but they are few and far between, IMO.  Some tuners are "old school" and want to set the bike up like they did before these bikes ran in closed loop mode most of the time...tuning a newer bike is a different ballgame.  It IS possible to get good fuel mileage AND get the most HP/TQ out of the bike at the same time, but it requires skill and patience.  And honesty.

A member here named Doc1 is one of the best in the country, but he's in Florida.  He trains people though.