Long-Awaited Dyno Results

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UselessPickles

Making Grand Canyon replicas from air boxes...
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I'll let the chart speak for itself first. These are SAE corrected (Wayne - the results we looked at on the computer and print-outs were uncorrected). Run 001 is Wayne's (extrememarine's) stock 2009 FJR, best of 3 runs. Run 006 is my modded 2008 FJR, best "overall" run (I'll explain later).

dyno_stock_vs_modded.png


Ouch...

Here's the dyno run files for those two runs:



Here's some video clips:






And you can download DynoJet's dyno run viewer here: https://www.dynojet.com/downloads/zip/7.5.2_Install_.zip

You'll have to unzip the files in a temporary folder and run the setup EXE file.

I knew my biggest gain would be in the mid-range from the air box mod, but I really didn't expect a loss in the higher RPMs. I based my expectations on Wicked Webby's dyno results from his air box mod adventure. He got gains everywhere, with the biggest being in the mid-range. Wicked Webby and I have the same slip-ons and air box setup. He has a stock header, while I have the Holeshot header. We have different devices for adjusting the fuel injection, but the difference in WOT performance due to this would be very minimal because we both adjusted fueling until we got maximum dyno results. I expected the Holeshot header to give me a bit more top-end with some sacrifice in low RPMs.

It's looking like it did just the opposite (except I still have a loss in the low RPMs too).

I'm now in the market for a used stock header. I should've kept mine.

At least I have an almost flat TQ curve for a large RPM range and some extra top gear freeway passing power.

EDIT: I now have reason to believe that it was actually over-oiled K&N air filters that caused my loss of higher RPM. My reasoning can be found here: https://www.fjrforum.com/forum//index.php?s...st&p=619163

EDIT (again): I'm pretty sure it was the Holeshot header now. I returned to a stock header and the resulting changes to my fuel map courtesy of my Motty AFR Tuner showed significant increases of fueling right where I had significant losses in my dyno results with the Holeshot header. Unfortunately, I also lost some of that huge mid-range gain (I'd guess about half of the gain is still there, but it's tough to tell from looking at fuel maps).

Now for some random bits of info:

  • The exhaust sniffer at the shop was consistently recording an A/F ratio about 0.2-0.3:1 higher than my Motty.
  • I got the best results between 3700 and 7700 RPMs when the Motty was targeting 13.2:1 AFR.
  • I was able to re-claim some of the lost low-end TQ (below 3700 RPMs) by installing the removable baffles in my Hexacones. My first pull with baffles in showed this gain, but it was also running leaner (as lean as 14.0:1 according to the shop's sniffer). As the Motty richened it up to meet target AFRs, the low-end torque was being lost again. Based on my earlier observation of difference in AFR readings, I have set my Motty to target 13.8:1 AFR at low RPMs and transition to 13.2:1 around 3700 RPMs.
  • The baffles did not significantly affect mid- to -upper RPMs.
  • I actually got the best results from 7700 RPMs to redline with the baffles in and a richer AFR. I've now setup the motty to transition from 13.2:1 to 13.0:1 around 7700 RPMs.
  • My "spliced" AFR target map is not "dyno proven" because I didn't fully analyze all the results during the dyno session.



Here's some graphs of the difference in TQ between the 2 bikes. These take into account the different best low (below 3700), mid (3700 - 7700) and upper (above 7700) RPM range results. It is not representative of any single dyno run on my bike, but should be close to what I will get from the transitioned AFR target map.

change_in_torque.png


My final thoughts on the results are (in ascending RPM order):

  1. Woo-hoo!
  2. D'0h!
  3. Woo-hoo!

 
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Good, bad, or indifferent, good info for the rest of us.
I still can't decide which of those 3 it is. It does give me overall faster acceleration, as evidenced by my 1/4 mile times. The low-end torque loss kinda sucks, but I suspect I'll get some of that back (and lose a bit of the mid-range gain) when I replace my air box.

If I can get a good deal on a couple quick dyno sessions, I might get results for both a completely stock air box and a partially modified air box. I expect that to mainly affect the distribution of torque between low- and mid-range RPMs. If that turns out to be true, then I'll know for sure that a stock header will give me my peak torque back.

 
In the mid-'60s, Cycle World did an in-depth story on aftermarket exhaust (stock, megaphones, open pipes, etc) and intake modifications (air filters, no a.f., velocity stacks, etc) on a, then popular, Honda -- using C.R. Axtell's dyno. When it was all over, they showed the most power (averaged) over the widest rev. range with all the stock pieces (mufflers and air filters) in place. They did show various peak improvements in localized rev. ranges with some of the other set-ups.

'The more things change, the more they stay the same'.... :huh: :blink:

Manufacturers have dynos, too.... :eek: :rolleyes: :)

Good on ya', for your attempts and report.

 
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As a guy who calibrates for a living, I respect your scientific approach and un-biased testing. Good on yah.

 
Question for ya.

you added the mods to the bike, but did you "tune" the bike to the mods via power commander or some other program source?

I just recently had my track bike tuned and with corrected numbers it is 126hp at the wheel (03 gsxr 750) A stock 06 750 on this same dyno puts down 106 with corrected #s

one of the first things he asked me was how do I want to tune it?

Max hp, fuel milage, combo of both, etc.

Also, another (slight) variation you could have is the fuel you had in the tank.

My Dyno tester Power-Tripp said as far as pump gas goes, he recommends Chevron 93 for the most consistant detonation paterns he has found (from the many he has tested)

So wa it just a dyno run or a dyno tune session? my tune session was 5 hours tweaking every little thing here and there

 
Question for ya.
you added the mods to the bike, but did you "tune" the bike to the mods via power commander or some other program source?
Yes. I have the Motty AFR Tuner on my bike that does the tuning for me; I just need to specify what air/fuel ratios I want under different conditions (combinations of throttle and engine speed). I was only focusing on 100% throttle on the dyno to find the best AFR for max torque. I did this by setting up the Motty to target a given AFR then do several dyno pulls until the Motty achieved its target AFR.

When talking about 100% throttle, there's no reason to take into account how you want the bike tuned (racing vs. fuel economy, etc) because no matter how you intend to ride your bike, you want max possible torque when you open the throttle all the way.

Everything below 100% throttle I have been tweaking just based on data logging (to determine what parts of the map are used for my common cruising speeds), calculated MPG and "feel" to get a certain balance of smoothness and fuel economy.

 
Jeff,

Thanks; this was fun. There is nothing like the sound of those Remus cans under load.

Like we spoke about, and you see on the graph, it's between 3600 - 5500rpm's where you're bike has made the biggest improvement over stock (mine). And that translated to the bike length jump you got when we did the 60-80 & 60-100 roll ons last time we rode.

I am still searching for the dyno chart from my 'O4; I'm know it's here somewhere. I'm pretty sure it was in the neighborhood of 128-130hp at the wheel /w the pcIII and custom map.

We will have to revisit this once I have a PC-V on the '09 this winter...

Wayne

 
Epic failure.?.?.

The stated difference between our bikes (besides your homemade KnN filters

not holding up).... Was your #1) Motty tuner, #2) the OVERSIZED Holeshot headers and #3) Who

was doing the tuning. Obviously, either the Motty tuner isn't

all its cracked up to be (ding!)...or the Holeshot header isn't all its

suppose to be(prolly not the case)....or the way it was tuned wasn't ideal (Ding! Ding!).

I suspect the 1st and the 3rd are the source to your problems. Guess all the

time gains you posted that the Motty tuner showed (with its high tech computer calculations) were

as debunk as it was. I gotta ask... Why are you targeting 13-14% AFR's when tuning for

max power?? Lean is mean in the mids but you need the top to be FAT for max HP (I thought

you would of known that.. but based on your post I thought I should remind you).

WW

 
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Epic failure.?.?.
The stated difference between our bikes (besides your homemade KnN filters

not holding up).... Was your #1) Motty tuner, #2) the OVERSIZED Holeshot headers and #3) Who

was doing the tuning. Obviously, either the Motty tuner isn't

all its cracked up to be (ding!)...or the Holeshot header isn't all its

suppose to be(prolly not the case)....or the way it was tuned wasn't ideal (Ding! Ding!).

I suspect the 1st and the 3rd are the source to your problems. Guess all the

time gains you posted that the Motty tuner showed (with its high tech computer calculations) were

as debunk as it was. I gotta ask... Why are you targeting 13-14% AFR's when tuning for

max power?? Lean is mean in the mids but you need the top to be FAT for max HP (I thought

you would of known that.. but based on your post I thought I should remind you).

WW
1) The Motty is doing it's job just fine. I tell it what AFR I want, and it gets there after a few dyno pulls.

2) As you pointed out, the pipes on the Holeshot header may be too big.

3) I'm tuned for max torque across the entire RPM range. My first runs started off lean around 13.8:1. The entire torque curve gained a bit as I richened it to 13.2:1, then I started seeing losses through most of the curve as I richened it more. The exceptions were the lower RPMs getting the best torque around 13.8:1 and very high RPMs (7700+) getting more torque around 13.0:1. That is "FAT", and the 13.2:1 throughout most of my RPM range is also quite rich, so I don't understand what it is about my fuel mixture that you are questioning. Even DynoJet recommends that max torque is usually found in the 12.8:1 to 13.4:1 range in their AutoTune user guide. I'm pretty sure that Power Commanders are typically tuned to a target of 13.2:1 for 100% throttle. What AFRs are you running throughout the RPM range?

4) The acceleration times that I reported from the Motty's data logger are backed up by my 1/4 mile times (10.8s @ 126mph). The improvement in 60-80mph and 80-100mph acceleration times make perfect sense because they involve the mid-range RPMs where I do have a huge gain. The improvement in 0-60mph and 1/4 mile times make sense because I launch in the mid-range where I have huge gains. Big improvements in initial launching/acceleration make for even bigger improvements in 1/4 mile times, so it more than compensated for the loss of torque in the 6k-8k range, and the slight gain at 8k+ probably helped a bit too.

I have the same huge gains in the mid-range that you showed with the air box mod, but something bad happens above 5500 RPMs. It has to be the header, or there's something wrong with my engine that causes it lose some torque 5500 and 8500 RPMs.

 
I just thought of another possible cause to my loss of higher RPM torque. I've heard that it's common for people to oil the K&N filters too much and actually reduce their ability to flow air (causing a loss in power). It's possible that I've made this same mistake. I may have reduced the air flow just enough to hurt higher RPM performance where higher airflow is needed. After I install my new air box with a stock filter, I'll go for quick dyno session. If my high end torque comes back, then this theory is proven to be correct.

I'd like to hear the sound!
I'll try to get the videos up tonight.

 
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These are on ebay

I have the stock header from my '07 sitting in my garage if your interested. No dents or anything. I won't be putting it back on so I'm not worried about needing it. Fair price plus shipping? I'll do better than that price

 
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These are on ebay
I have the stock header from my '07 sitting in my garage if your interested. No dents or anything. I won't be putting it back on so I'm not worried about needing it. Fair price plus shipping? I'll do better than that price
Thanks for the offer. I think I'd like to test my "too much oil on my K&N filters killed my high RPM torque" theory before I invest the money and time to try a stock header. I'll send you a message either way when I decide what to do.

 
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