Long-Awaited Dyno Results

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GOOD SCIENCE! a lot of times i read things where mods do this or that .\ obviously confusing effort with results :rolleyes: you've done an excelent test and displayed facts! thank you so much!

 
I see no mention of temp or pressure. Even the same dyno can give different results on differents days. I'm assuming you took these factors into account. I think dyno numbers are a bit misleading at times.

 
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.

UPs,

I sure hope you don't have any lasting damage from them defective KnN's coming apart....

How do you know that the Motty is doing what it is suppose too.?.? Did you calibrate the wideband

sensor on the Motty? You know.. To insure that it is reading AFR's correctly? Something

is seriously wrong with your setup to be so close to a stock bike. If anything.. The larger header

might reduce peak tq, but not peak Hp. Over oiled filters would restrict air but you should of been able

to see that on the dynos sniffer. How did the dyno's sniffer compare to the Motty's results?

My setup on my '07A liked a lot more fuel than yours:

https://www.fjrforum.com/forum//index.php?s...hl=wicked+webby

I was tuning around 900 above sea level.

Maybe your bike was built on a Friday?

WW

 
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I have seen a bike with so much oil in the K&N that is was being sucked into the intake valves. That bike acutally caught on fire and the filter burned up pretty bad. The bike was saved and it only needed a new air box.

 
I see no mention of temp or pressure. Even the same dyno can give different results on differents days. I'm assuming you took these factors into account. I think dyno numbers are a bit misleading at times.
Both bikes were tested on the same dyno on the same day. Results are SAE corrected to take into account the change in temperature and humidity between runs.

I sure hope you don't have any lasting damage from them defective KnN's coming apart....
I doubt that's the case since I had the very strong mid-range just like you and a strong very high end (8000+ RPMs)

How do you know that the Motty is doing what it is suppose too.?.? Did you calibrate the wideband
sensor on the Motty? You know.. To insure that it is reading AFR's correctly? How did the dyno's sniffer compare to the Motty's results?
I calibrated my sensor a couple days before the dyno session. I did mention that there was about a 0.2:1 AFR discrepancy between the shop's sniffer and what the Motty reported. I don't know when the shop last calibrated their sniffer. If my sensor was wrong and the shop's sensor was right, then I'm still running around 13.4:1 in the mid-range and 13.2:1 in the high end. This difference in AFR wouldn't cause such a big difference in performance. Also, my loss of performance is only in a certain RPM range. My mid-range shows huge gains, and the higher RPMs that suffered the loss are running similar or slightly richer than the mid-range. This indicates that AFR is not the cause of my loss.

Over oiled filters would restrict air but you should of been able to see that on the dynos sniffer.
The dyno's sniffer would not detect this condition because the Motty adjusts fueling to get a desired AFR. If my air filters are restricting high RPM air flow, then the Motty is simply not adding as much fuel as it would if they were not restricting air flow. Whether they are restricting air flow or not, the dyno would detect the same AFR.

If anything.. The larger header might reduce peak tq, but not peak Hp.
I did some searching and found some dyno charts showing that a full Holeshot system with a custom-mapped PCIII provides gains through the entire mid and high RPM ranges. I can't imagine how the Hexacones could be so different from the Holeshot slip-ons that they would kill my torque curve up there, so I think it's safe to assume that the Holeshot header is not the problem.

So, I have huge mid-range gains that almost match your mid-range gains exactly and small very high-end gains, indicating that my engine is running strong as expected in those areas. My AFRs are very consistent throughout the RPM range, meaning that fueling is correct (or at least close enough to correct) for the amount of air flowing through. Both the Holeshot header and your air box mod have been proven on the dyno to provide gains where I suffered a loss.

I think the only logical explanation is that something is restricting the high airflow required at higher RPMs. When I cleaned my K&N filters, I questioned myself on the amount of oil I was applying and thought I might have over-done it a bit. I patted them down with a paper towel to soak up a bit of the oil and called it good enough. The more I think about it, the more the evidence points to over-oiled air filters restricting airflow.

 
Hi UP

I've checked your dyno runs against mine, you've some torque improvement over stock low down, but like my experience with the holeshot headers, you lose out elsewhere. As I have said before, my main aim was to achieve a super smooth throttle response, whilst maintaining good fuel economy-its a tourer after all. If I could increase power and torque as well that would of been a bonus, but that was not achieved.

When I returned to my original headers, installed my custom map from Dynojet UK, my MPG improved significantly, from 35 mpg to mid 40's mpg. You can see on the Dynojet USA website, both my fueling maps, the holeshot fuel map needs lots of adjustment to achieve a constant AFR, this is where mpg is being sacrificed.

I hope you are able to get a replacement OE headers cheaply.

Andy

 
you've some torque improvement over stock low down
You must have looked at the charts wrong. I have a big low RPM loss, a big mid RPM gain, a smaller high RPM loss and a slight very high RPM gain.

You were running stock mufflers on your Holeshot header, right? The header might need to be paired up with free-flowing mufflers in order to perform well. I did some searching and did find dyno results of before/after installing a full Holeshot system that showed decent gains in the high RPMs where I have a loss. That's what's making me think the header is not my problem there and that it's air restriction at the air filters.

 
UP

What is your primary roll of your FJR, is it a flat out speed monster or a 80 mph mile cruncher with the odd blast in between?

If its the former then I believe it's the wrong bike for purpose, if the latter then why go to such efforts for little return.

Andy

 
UP
What is your primary roll of your FJR, is it a flat out speed monster or a 80 mph mile cruncher with the odd blast in between?

If its the former then I believe it's the wrong bike for purpose, if the latter then why go to such efforts for little return.

Andy
Somewhere in between maybe?

As for why... because I'm the type of person that must tweak and tinker with stuff. I had some extra money from the insurance payout when my last FJR was totaled, so I decided to have some fun experimenting. I know there's plenty of bikes that are way faster than the FJR, but I like the FJR. Acceleration was not the primary factor in choosing a bike, but I'd still like to get as much acceleration as possible out of the bike I chose.

 
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Let me try to help you understand what is going on here. This is not hard.

No matter what you do to a stock bike, you can only go so far as to make it sound better. ( if you think louder is better) and smooth out some lean spots due to emission requirements. That being done by computer mods.

By opening up air boxes and exhaust systems, you are only going to help the engine breath more freely.

Now, unless you get more air and fuel into the cumbustion chamber, this is all useless.

So, more air flowing through the air box needs bigger valves and head porting to let that air into the cyl. then you need bigger cams to open the bigger valves more and for a longer duration to get it all in there. Now for higher compression pistons to squish everything down nice before the big bang and you're all set to break some parts. :rolleyes:

Just my 2cents. I'll shut up now.

Tim

 
UP
What is your primary roll of your FJR, is it a flat out speed monster or a 80 mph mile cruncher with the odd blast in between?

If its the former then I believe it's the wrong bike for purpose, if the latter then why go to such efforts for little return.

Andy
Somewhere in between maybe?

As for why... because I'm the type of person that must tweak and tinker with stuff. I had some extra money from the insurance payout when my last FJR was totaled, so I decided to have some fun experimenting. I know there's plenty of bikes that are way faster than the FJR, but I like the FJR. Acceleration was not the primary factor in choosing a bike, but I'd still like to get as much acceleration as possible out of the bike I chose.
c'mon … because it's friggin funny as hell to pull up on a squid on an RR or a Gixer and smoke em because; one they weren't expecting it from that bike, and two; because most of the kids can't ride as well. Specially when the just bought an over powered racebike way too much for their abilities and when they juice it from the line they either stall it or pick the front up so fast they get scared and back off.

I don't mess with everyone on the crotchy's but I can spot the ones I want. :lol:

they must be like

" dude , epic fail today!"

"what happened"

" some old guy on a big… like I dunno like a small goldwing, like totally pwned me today"

"awe dude that sucks ***!"

" ya think your older brother will get us some beer?……"

 
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...By opening up air boxes and exhaust systems, you are only going to help the engine breath more freely.

Now, unless you get more air and fuel into the cumbustion chamber, this is all useless.

So, more air flowing through the air box needs bigger valves and head porting to let that air into the cyl. then you need bigger cams to open the bigger valves more and for a longer duration to get it all in there.

...
That is all true if the ports/valves were the airflow bottleneck to begin with. Air box and exhaust are often the bottleneck. This has been proven to be true on the FJR by performance increases when replacing stock mufflers with slip-ons, and then even more performance increases shown by Wicked Webby when you open the air box up in addition to slip-ons. The exhaust and air box mods allow more air to enter the combustion chamber. The last piece of the puzzle is matching the extra air with extra fuel with a custom-mapped Power Commander, a self-tuning Power Commander V + AutoTune or Motty AFR Tuner, or manual tuning with a wideband O2 sensor with AFR readout/logging and a means to adjust fueling like a Techlusion.

That said, there will be a limit to gains via exhaust/intake mods once you modify it to the point that the head of the engine becomes the bottleneck. That's when you'll have to do engine modifications to see any more gains (or add NOS and/or a turbo/super charger). That's when it gets way too expensive and I will stop.

I obviously have something abnormal going wrong that caused the higher RPM losses, and I think I've logically narrowed it down to over-oiled air filters restricting airflow at high RPMs. The low RPM loss could be caused by either the Holeshot header or the air box mod. Wicked Webby's dyno charts don't start at as low RPMs as mine, so his results are inconclusive for the low RPMs where I have a loss. I personally talked to Dale Walker, and he claimed that his tests did not show loss of torque anywhere, and that if there was a loss, it would be a "small loss" at "very low" RPMs. Dyno results after I put a less radically modified air box on my bike with a stock paper air filter will hopefully solve these mysteries.

 
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Did Webby use a PC or did he do all the fuel tuning through the barbarian mod?
His initial tests of the air box mod were just using the Barbarian mod. Now he uses a Techlusion, which allows you to make broad adjustments to low, mid and high RPMs. He was using some sort of wideband O2 sensor with a digital display to monitor air/fuel ratios as he made adjustments. I'm sure he'll respond with specifics and links.

 
Did you dyno your bike before the mods? IMHO you can't really know the changes comparing it to another bike. Production tolerances, mechanical wear & tear on parts and other factors prevent any two of the exact same make & model bikes from getting the exact same results. You may have gained power where you think you lost it and lost power where you think you gained it.

 
Did you dyno your bike before the mods? IMHO you can't really know the changes comparing it to another bike. Production tolerances, mechanical wear & tear on parts and other factors prevent any two of the exact same make & model bikes from getting the exact same results. You may have gained power where you think you lost it and lost power where you think you gained it.

Nope. I did most of the work to my bike right when I got it in the middle of winter in Michigan before the bike was broken in. Wasn't going to dyno it at that time, and I wasn't going to waste the winter waiting for spring to come around so I could break the bike in and dyno it.

I think comparing my bike to a stock bike on the same dyno on the same day is good enough. Both bikes were low mileage at the time. Manufacturing tolerances would likely be a fairly insignificant contributor to the differences in the torque curves I showed. The torque curves are completely different shapes. If the torque curves were the same exact shape with one bike having only 2 HP over the other, then I'd be more suspicious of manufacturing tolerances being a significant contributor.

 
I got my 07 dyno this past weekend. I have two brother's slip-on exhaust K&N air filter and a PC-5. Max power= 125.28 Max torque=89.78. I was more concerned that the fuel maps were right. I bought the pc from fuel moto and they premapped for me. They checked the fuel/air ratio and it all looked great. I've been very happy with this set up. I think the bike looks and sounds better. The added torque and hp is also a big plus.

 
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