Help interpreting dyno results

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Oct 1, 2010 | 06:57 AM

#31

sgod1100

Road Captain

Joined: Dec 2009

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From: Rockford, IL

Quote:

Originally Posted by Faast Ed

I gave up some top end power in order to gain torque in the lower ranges where I spend a lot of time at. I have no regrets.

Yeah i noticed that....what cam is in yours? I like having the top end power! Just depends on what you like

Oct 1, 2010 | 07:06 AM

#32

sgod1100

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Joined: Dec 2009

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From: Rockford, IL

I was definitely surprised that the OP said that the tuner only did 4 runs!!! Ya can't get much tuning done in that little amount of time. When i had my bike dyno tuned it took around 3-3 1/2 hours with countless WOT runs and just cruising tuning (Each cylinder tuned individually along with the necessary timing changes). I would assume that this is the PROPER way to tune a bike..

Oct 1, 2010 | 08:40 AM

#33

Faast Ed

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Joined: Sep 2009

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From: The Internet (& Dyer, Indiana)

Quote:

Originally Posted by sgod1100

Yeah i noticed that....what cam is in yours? I like having the top end power! Just depends on what you like

Andrews 54's. Fairly mild of a cam, but very well mannered. Pulls hard in the ranges I spend most of my time in, with a little room for playtime at the top. If you look again at my sheet, it's not like the power totally dissapears on the right side of the sheet. Shifting near the rev limit feels plenty good, and the early shifts feel even better.

StrokerJlk,
Nice to read your stuff. Thanks for posting up!

Oct 1, 2010 | 01:06 PM

#34

strokerjlk

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Joined: Jul 2010

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Quote:

StrokerJlk,
Nice to read your stuff. Thanks for posting up

no problem good to run into you again. I wondered where you were hanging out.

Oct 2, 2010 | 10:22 AM

#35

Dalton

Ultimate HDF Member

Joined: Feb 2007

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From: Northeast Ohio

Quote:

Originally Posted by Faast Ed

Only 4 passes between the before/after runs.
Not much tuning could have possibly been done. You likely have some ponies left on the table. And don't expect miracles in the lower ranges.

My bike was tuned in several different RPM ranges and in different gears.
Timing as well as AFR. Each cylinder done separately.
The tuner tried to recreate several different riding scenarios.
It took 67 passes to accomplish this. The bike rides like a dream.

Not much he could have done in 4 passes. I hope he didn't charge you much.

I am not sure of the number of passes as Strokerjlk is correct, at times not all runs are "recorded". I tune my own bikes for the most part and for others also, but without a dyno but with the proper equipment to measure A/F and timing. That said, I did have my 120" Ultra tuned by a very competent shop, and there were over 60 pulls made in all rpm ranges and loads. Without this being done, rideability is never spot on with the "quickie" tune that a lot of shops provide.

Quote:

Originally Posted by Watch Guy

I can't believe that dyno run results of HP and Tq come from that AFR

Don't focus so much on the AFR, a properly tuned bike may or may not have a flat AFR. You have to give the engine what it needs at all rpm ranges at WOT. Due to variencies in efficiencies at different rpms, you may not need to be at 13.2 across the board to provide max power. And for some builds, you may need to be much richer, such as higher compression, long duration builds, they might need as low as 12.6 or 12.8 to provide the max power without a hint of detonation. Tuning is just giving the engine what it needs at each throttle and load.

Last edited by Dalton; Oct 3, 2010 at 07:16 AM.

Oct 2, 2010 | 12:11 PM

#36

Faast Ed

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From: The Internet (& Dyer, Indiana)

I'd love to see a copy of his PC III timing map, the top two throttle positions.

Typically they are advanced some for cam upgrades. 2 or 3 degrees.
There are a few exceptions to that. (SE 204's for one, don't like timing advance).