Author Topic: Reflash vs pulling flys  (Read 6697 times)

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Offline 46Alpha

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Reflash vs pulling flys
« on: April 23, 2012, 04:21:20 pm »
Ok, so I've been reading as much as I can on my new bike. I don't think I've seen this addressed specifically (If I missed it, sorry).

Can someone break down the differences between getting the ECU flashed vs pulling the secondary flys? From what I know, both are reversible and neither voids the warranty. Aside from the cost standpoint, are there other differences I should be aware of? Does one work better with either a stock/aftermarket exhaust?

TIA for your help.

Offline Gypsy JR

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Re: Reflash vs pulling flys
« Reply #1 on: April 23, 2012, 05:29:44 pm »
Traction control uses the secodary butterflies to limit wheelspin etc.

If you pull the flies you take that away from TC.

A flash like Guhl does still allows TC to use the secondary butterflies.
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Offline Big Mike

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Re: Reflash vs pulling flys
« Reply #2 on: April 23, 2012, 05:57:32 pm »
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Offline BDF

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Re: Reflash vs pulling flys
« Reply #3 on: April 23, 2012, 06:00:49 pm »
First the warranty issue: I suspect both would get in the way of a warranty claim should something like internal engine damage occur to the bike. Overall, no, neither one would impact the general warranty- there is no way anyone could point to an engine control mechanism alteration and claim that led to, say, leaking brakes.

There are advantages and disadvantages to both.

Reflashing the ECU
Advantages:
1) nothing new added to the bike and no new electrical connections so fewer things to fail.
2) It is easier to remove and reinstall the ECU than add a Power Commander.
3) Less risk: not having to take out the secondaries means there is no possibility of breaking a screw(s) during the removal so the process is 100% reversible.

Disadvantages:
1) Changes cannot be made; the unit is reflashed with whatever code the person doing the reflash uses and it is not adjustable or alterable.
2) It is expensive to go back to stock as another re-flash is required with the associated cost (compared with simply removing a Power Commander).
3) No cost can be recovered; if the ECU is reflashed twice, once to alter the unit and again to return to stock, there is nothing left of the money spent. If a P.C. is used and removed, the P.C. can be sold on the used market.

Installing a P.C. V:
Advantages:
1) no downtime as it is user installed.
2) slightly less expensive to begin with and far less expensive for the second change (free with a Power Commander, it would take another re-flash if changing the ECU).
3) Secondary butterflies ('flies) are fully removed and max. performance available. An ECU re-flash may open the secondaries sooner but removing them guaranties they are always fully open.
4) The owner can adjust the mixture or change maps at will easily and at no cost. This is an advantage should something else be changed on the bike such as an exhaust system. An exhaust system change alone would not require a new map or a re-flash but that does not mean the bike would not benefit from a different map.
5) Auto tuning can be added to a P.C. that will adjust the mixture on your specific bike. In fact, it was a Power Commander and auto tuning that generated the maps used by some people who re-flash the ECU (ironic, huh?).
6) It is far more economically feasible to try a Power Commander and then, if desired, move to a re-flash and sell the P.C. Going the other way will be seriously expensive (the cost of two re-flashes and a P.C.- something over $1,000, and there is nothing to sell).

Disadvantages:
1) Adding a P.C. adds another component to fail. Some people have had P.C.'s fail on them and the bike is down until the P.C. is removed.
2) It requires fairing removal to install a Power Commander (the ECU only requires the removal of the toolbox).
3) It requires manually removing the seconday butterflies to make a big change in the power available at low- to mid RPM. Removing the 'flies is time consuming and has often caused broken screws. If that happens, the odds of being able to replace the 'flies goes down by quite a lot; they are small screws located in the throttle plate rod, well down in the throttle body bores.

Both work and I think it is up to the individual to choose which one applies best to him / her. I have an '08 with a PC III and am fully satisfied with it; if buying a new C-14 today, I would install a P.C. V with the tuning module and O2 sensor.

Brian


Ok, so I've been reading as much as I can on my new bike. I don't think I've seen this addressed specifically (If I missed it, sorry).

Can someone break down the differences between getting the ECU flashed vs pulling the secondary flys? From what I know, both are reversible and neither voids the warranty. Aside from the cost standpoint, are there other differences I should be aware of? Does one work better with either a stock/aftermarket exhaust?

TIA for your help.
« Last Edit: April 23, 2012, 06:04:49 pm by BDF »
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Offline Fred_Harmon_TX

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Re: Reflash vs pulling flys
« Reply #4 on: April 23, 2012, 06:25:32 pm »
Don Guhl doesn't charge you to reflash your ECU to stock. All you have to pay is shipping.

I've actually done both. First I pulled the butterflies (on both my 08 and my 2010) and installed a Power Commander. Then I reinstalled the butterflies on the 2010 and removed the ECU and had it reflashed.

My personal preference would be to reflash the ECU. And in light of the issues with the traction control when you remove the butterflies, I think this is really the only good option on the 2010-2012 bikes.

Also, keep in mind that Fuel Moto is no longer supporting the 2010-2012 C14's and have not made any maps for them and have never had a 2010-2012 on the dyno. I think the last map Fuel Moto made for the C14 was back in 2008. So if you get a Power Commander, you're either going to have to pay someone to put the bike on a dyno and get a map made for it, or else buy the AutoTuner module and remove the header and get a bung welded on it for the O2 sensor. I've done this as well, and it's not a bad way to go, but it still leaves the issue with the traction control unresolved. It's also quite a bit more work and is more expensive than a reflash.
« Last Edit: April 23, 2012, 06:43:33 pm by Fred_Harmon_TX »
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Offline BDF

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Re: Reflash vs pulling flys
« Reply #5 on: April 23, 2012, 06:49:16 pm »
What issues Fred? All the reports that I have heard were positive regarding removing the 'flies and traction control. ?? Can you point to any reported issues?

I have no connection or financial benefit with any re- flashing service nor do I have any connection or financial benefit with DynoJet (mfg's of Power Commanders), I just think the Power Commander coupled with removing the 'flies is the better, more flexible option.

Brian



And in light of the issues with the traction control when you remove the butterflies, I think this is really the only good option on the 2010-2012 bikes.


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Offline Fred_Harmon_TX

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Re: Reflash vs pulling flys
« Reply #6 on: April 23, 2012, 06:54:26 pm »
What issues Fred? All the reports that I have heard were positive regarding removing the 'flies and traction control. ?? Can you point to any reported issues?

I have no connection or financial benefit with any re- flashing service nor do I have any connection or financial benefit with DynoJet (mfg's of Power Commanders), I just think the Power Commander coupled with removing the 'flies is the better, more flexible option.

Brian



And in light of the issues with the traction control when you remove the butterflies, I think this is really the only good option on the 2010-2012 bikes.



The traction control does not engage as smoothly with the butterflies removed, and is jerky in it's operation. It also can cause some serious backfiring in the exhaust when it engages if the butterflies are removed. It still functions, but there is no doubt that it has been impacted.

And just for the record, I don't have any financial interest in Guhl Motors, Fuel Moto, or Power Commander either. I just think the reflash is a cleaner, easier way to go. But everyone will have to make up their own minds what works best for them.
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Offline 46Alpha

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Re: Reflash vs pulling flys
« Reply #7 on: April 23, 2012, 10:01:04 pm »
Great info, thanks much! I guess I was confused. Is a PC needed to take full advantage of pulling the flies? From reading some posts, it seems some have had great success in just pulling the flies only.

I've gone the PC route on my other bike (06 VFR800) to help smooth out the Vtec engagement. Had a custom map done, exhaust and BMC air filter. My experience was a lot of cash with very little reward.

Offline Jeremy

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Re: Reflash vs pulling flys
« Reply #8 on: April 23, 2012, 10:25:56 pm »
If you pull your flies you should probably use some sort of tuner to make sure your air/fuel stays at a safe level.  I think there are several people that have gone without a tuner who had pulled their flies but I wouldn't want to tear up a motor when $300-$400 could have prevented it.
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Offline BDF

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Re: Reflash vs pulling flys
« Reply #9 on: April 23, 2012, 11:52:00 pm »
The short answer is: I don't know.

The longer answer is that I would not remove the 'flies and not use something to enrich the mixture. Others have done it with at least short term success but the long term consequences have never been reported as far as I know. Certainly the engine won't burn up in 10 minutes running that way but I do believe it will run lean at low RPM and moderate to large throttle openings.

Here is an example of what will happen- the numbers are not accurate, just for example. The stock bike has two sets of throttle plates ("flies"), you control one directly and the ECU controls the other set. The ECU will not open the secondary plates until ~7K RPM under large throttle openings. So what happens at 4K RPM when you go from 5% throttle opening to 25% throttle opening is that the ECU may hold the secondaries to 10% open at that speed. When you remove the 'flies and change the throttle the same way, the engine gets a lot more air because the ECU is still injecting the correct amount of fuel for a 10% throttle opening but it is really open 25% because the 'flies have been removed. The ECU can not and does not compensate for the extra air. So the real question is how much more lean will the bike run, and for how long (at high RPM the 'flies would be wide open anyway so the mixture is not altered in that range)? A 2 second burst of <slightly> lean running now and then certainly won't do any harm but we really do not know how lean and how often those lean periods occur.

As Jeremy already said, for $300, it just isn't worth it not to put a Power Commander in the bike if removing the 'flies. Just my opinion of course.

Brian

Great info, thanks much! I guess I was confused. Is a PC needed to take full advantage of pulling the flies? From reading some posts, it seems some have had great success in just pulling the flies only.

I've gone the PC route on my other bike (06 VFR800) to help smooth out the Vtec engagement. Had a custom map done, exhaust and BMC air filter. My experience was a lot of cash with very little reward.
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Offline ZG

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Re: Reflash vs pulling flys
« Reply #10 on: April 23, 2012, 11:57:18 pm »
If you pull your flies you should probably use some sort of tuner to make sure your air/fuel stays at a safe level.  I think there are several people that have gone without a tuner who had pulled their flies but I wouldn't want to tear up a motor when $300-$400 could have prevented it.

Or just have it mapped on a dyno, that's what I did, A/F is perfect! :great:
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Offline Mad River Marc

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Re: Reflash vs pulling flys
« Reply #11 on: April 24, 2012, 12:09:23 am »
Would there be any advantage to installing a PC  with autotune WITHOUT pulling the flies?

I had a PCV on my FJR and the only reason I had it was because the bike was pretty lean from the factory and richening it up a bit made it idle and accelerate smoother, just wondering if something like that would help a C-14, 

I have no interest in pulling the flies as I feel the low end torque is plenty for my riding style (I'm just not an aggressive rider) and while the reflash is the cleaner route it has one drawback that bothers me (The same drawback that the OEM ECU does) and that is it is not measuring the exhaust and compensating to keep the AF in that sweet spot regardless of outside conditions (Unless I am missing something and the reflash or PV without autotune would do the same thing because of the bikes other sensors)

Just curious...
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Offline BDF

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Re: Reflash vs pulling flys
« Reply #12 on: April 24, 2012, 12:20:18 am »
Yep but that only works after a P.C. is installed, otherwise the tuner cannot adjust anything.... the ECU is not available to adjust the mixture when the bike is being tuned.

Brian


Or just have it mapped on a dyno, that's what I did, A/F is perfect! :great:
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Offline BDF

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Re: Reflash vs pulling flys
« Reply #13 on: April 24, 2012, 12:31:34 am »
Yes but not as much advantage as there was on the FJR. FJR's are significantly out of tune from the factory so it is very common to adjust the ECU (commonly known as the 'barbarian mod.') and adding a Power Commander with a smoothing map, specifically designed to reduce vibration. A C-14 (or ZX 14 for that matter) is already well tuned and running pretty well from the factory so the benefits of adding a P.C. alone are not that great IMO.

As far as not having auto tuning, it really is not all that big of a deal really. These bikes, at least those in the US and Canada, run what is called open loop which means there is no real time compensation for the actual mixture being used by the engine as most autos have these days. That said, the ECU does compensate blindly to ambient temperature, outside pressure (altitude density), engine temperature and several other factors and really does do a fine job of gauging the mixture. Put it another way: the open loop mixture control of a C-14 is miles ahead of carburetion and that worked <reasonably> well for decades.  Closed loop tuning is even better but the greatest benefits are in emissions, not performance or running qualities. One other thing to remember is that even closed loop systems go open loop (by ignoring the O2 sensor(s)  and using nothing but predetermined maps and charts) at high throttle settings because O2 sensors are not fast enough to compensate for sizeable errors fast enough to maintain proper control of the mixture and timing. The 'rule of thumb' for when to change over to open loop control is 70% throttle opening regardless of engine speed.

You can look up lots more info. about how all of this works. The specific scheme the C-14 uses is known as Alpha- N if you are interested. The common control method used on closed loop autos is speed- density, and that requires a mass air- flow sensor which does not work very well on individual plenum intakes such as individual throttle bodies used on most motorcycles. The whole thing gets pretty involved but is very interesting, at least to me.

Brian


Would there be any advantage to installing a PC  with autotune WITHOUT pulling the flies?

I had a PCV on my FJR and the only reason I had it was because the bike was pretty lean from the factory and richening it up a bit made it idle and accelerate smoother, just wondering if something like that would help a C-14, 

I have no interest in pulling the flies as I feel the low end torque is plenty for my riding style (I'm just not an aggressive rider) and while the reflash is the cleaner route it has one drawback that bothers me (The same drawback that the OEM ECU does) and that is it is not measuring the exhaust and compensating to keep the AF in that sweet spot regardless of outside conditions (Unless I am missing something and the reflash or PV without autotune would do the same thing because of the bikes other sensors)

Just curious...
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Offline Mad River Marc

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Re: Reflash vs pulling flys
« Reply #14 on: April 24, 2012, 12:51:46 am »

You can look up lots more info. about how all of this works. The specific scheme the C-14 uses is known as Alpha- N


Thank you Brian!!!  That actually clears up a big piece of confusion for me,  I didn't realize it only uses Throttle Position/RPM to make a determination I thought it was like a car and had either a MAF/AFM sensor or some additional method to measure engine load which would have compensated (at least a little) for flies being removed etc... 

Thanks again man!  Once again the font of knowledge you possess amazes me :)

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Offline Fred_Harmon_TX

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Re: Reflash vs pulling flys
« Reply #15 on: April 24, 2012, 01:13:16 am »
Speed density works off the manifold air pressure (MAP) and intake air temp (IAT) sensors along with a Volumetric Efficiency (VE) table to calculate air flow, and is used instead of a mass air flow (MAF) sensor, which the C14 does not have. With the temperature of the air known and the pressure, mathmetics can determine speed and density of the air flow if the VE for the system is known. This is why changing to an aftermarket pipe can have a big impact, because it totally changes the VE of the whole system and can even get reflected back to the MAP sensor. So all the air calculations are now off.

Alpha N is a bit more rudementary and simply uses lookup tables and then applies correction factors to those values based on sensor input from the IAT and MAP, but it doesn't do any actual flow calculations like speed density does. Speed density is generally considered superior to alpha N.


My understanding of the programming of the C14 ECU (from Don Guhl) is that it uses speed density calculations at the lower and mid range RPMs, and then switches to alpha N at some higher RPM. I'm not sure I fully understand exactly why, but the basic premise is that speed density works better at low RPM and alpha N is better at high RPM's, so Kawasaki programmed the ECU to be able to do both. And since Don has downloaded and disected the ECU code, I assume he is correct.

My first guess why they switch over to alpha N at higher rpms would be that the time to do the actual speed density calculations may make it hard for the ECU to keep up with the engine when it is running at 8K rpms, but that's just a guess on my part.
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Offline rcannon409

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Re: Reflash vs pulling flys
« Reply #16 on: April 24, 2012, 01:14:05 am »
I ordered my PCV and it took a few days to arrive. That same day I removed the "Files" just to get a head start on the project. No idea what I was getting in to other than the instructions (great) here on the site.  Abotu 30 minutes later, th ebike was buttoned back up and ready to ride, so I did.

Just removing the files did nto do much.  It felt slightly stronger down low, but probably not worth doing in and of itself.  I did nto notice anythign bad happening, just very little difference.  I was sort of disappointed at that point, but did not cancel the PCV order.

Once The PCV was plugged in, with a Fuel Moto map, the bike came alive.    Low end power was much, much improved. Throttle response was amazing, and the bike picked up a hit at 6000 rpm's that was unreal.  For me, the PCV is worth its cost, and then some. Interestingly though, the pcv (leo vince pipe, files removed map) added fuel in only one spot...right about 5000-7000 rpm's at 20-40% throttle. Making things more rich, across the board, would not help at all.

To be serious now, Its not as if the bike NEEDS more power, response, or anything else.  If you want to improve power, its going to cost some money. 300, or so for a remap or pcv.

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Re: Reflash vs pulling flys
« Reply #17 on: April 24, 2012, 01:21:43 am »
Just removing the files did nto do much.  It felt slightly stronger down low, but probably not worth doing in and of itself.  I did nto notice anythign bad happening, just very little difference.  I was sort of disappointed at that point, but did not cancel the PCV order.

This has been my experience as well. I have done some experimentation and just removed the secondary butterflies only and the change in low end torque and power was pretty insignificant, and was much less than I had expected.

I've also left the secondary butterflies in, and just put a Power Commander on with a better map for the stock bike, and I was actually surprised how much of an improvement the Power Commander made all by itself with the secondary butterflies still in the bike.

But as I've said before, if you want the whole enchilada, you have to do BOTH. Removing the butterflies gets rid of the restriction at low RPM and helps with throttle response, while putting the Power Commander on helps get the fuel correct which lets the engine make more power.

Reflashing the ECU essential does both of these things in one shot, by reprogramming the butterflies and correcting the fuel.
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Offline ZG

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Re: Reflash vs pulling flys
« Reply #18 on: April 24, 2012, 01:26:48 am »
Yep but that only works after a P.C. is installed, otherwise the tuner cannot adjust anything.... the ECU is not available to adjust the mixture when the bike is being tuned.

Brian


Or just have it mapped on a dyno, that's what I did, A/F is perfect! :great:

Yes, true Brian. I have a PCV, sorry if I missed the part about pulling flies without doing a PC, I thought that was the discussion (reflash vs PC and flies pulled).  :truce:
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Offline BDF

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Re: Reflash vs pulling flys
« Reply #19 on: April 24, 2012, 01:40:49 am »
Hey, no problem, I just wanted to try and be clear for anyone looking on. The whole thing can be confusing and a little daunting to the novice and there really is a lot going on regarding engine tuning.

I think I had actually written a little chart to help explain the different things that can be done to a C-14 (removing 'flies, adding a P.C., having an ECU re-flashed, and how they integrated) but I don't remember where it was or even which forum it was on. If it was the other forum it is probably gone now anyway.

I guess the good news is that we actually have choices. While we can debate about which method is best, I think we would all agree that having choices is always a great thing for the end user.

Brian


Yes, true Brian. I have a PCV, sorry if I missed the part about pulling flies without doing a PC, I thought that was the discussion (reflash vs PC and flies pulled).  :truce:
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Offline BDF

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Re: Reflash vs pulling flys
« Reply #20 on: April 24, 2012, 01:49:00 am »
The major difference between <most> motorcycles and <most> autos is the common plenum. A Mass Airflow Sensor only works well in a stable, damped flow environment. That means that a common intake manifold is basically required to make a MAF sensor work correctly; in individual intake devices like our bikes use (individual throttle bodies or carburetors, no common intake melding point) the airflow is too choppy for an accurate measurement. Same thing holds true for a Manifold Air Pressure sensor (MAP)- the individual throttle bodies create too much 'stop and go' airflow for accurate measurements. So really it is physics governing the mixture control scheme rather than some plot on the part of the manufacturers to make the system cheaper or simpler.

By the way, a common plenum on an air intake reduces intake velocity and that in turn reduces throttle response and throttle 'crispness'. That is why a single large throttle body and injector is NOT used on motorcycles. It would actually be less expensive to manufacture a common plenum system for motorcycles but the performance would suffer, especially at part throttle and low and mid- range RPM use.... which is exactly where we spend most of our time when riding bikes. There would be little difference at wide open throttle and high RPM use.

Brian





Thank you Brian!!!  That actually clears up a big piece of confusion for me,  I didn't realize it only uses Throttle Position/RPM to make a determination I thought it was like a car and had either a MAF/AFM sensor or some additional method to measure engine load which would have compensated (at least a little) for flies being removed etc... 

Thanks again man!  Once again the font of knowledge you possess amazes me :)

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Re: Reflash vs pulling flys
« Reply #21 on: April 24, 2012, 11:43:27 am »
I am happy with my PCV/Auto Tune combo, plenty of power when I want [notice I didn't say need] and 42+ mpg when I have [notice I didn't say want  ;D ] to slab it..  I don't ride a Harley so finding a dyno operator in my area is quite a challenge. 
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Re: Reflash vs pulling flys
« Reply #22 on: April 24, 2012, 12:50:31 pm »
I'm wondering if pulling the flies on a C14 has less effect than it does on a ZX14 ??

I know when I pulled the flies on the ZX14 it made a huge difference down low, there was nothing subtle about the power it was in your face right off idle..  ;D
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Offline Fred_Harmon_TX

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Re: Reflash vs pulling flys
« Reply #23 on: April 24, 2012, 12:56:20 pm »
I am happy with my PCV/Auto Tune combo, plenty of power when I want [notice I didn't say need] and 42+ mpg when I have [notice I didn't say want  ;D ] to slab it..  I don't ride a Harley so finding a dyno operator in my area is quite a challenge.

The PCV and autotune is a great combination, and it allows the bike to make fuel adjustments on the fly, which is one thing that the reflash can't do. You can actually just leave the auto-tuner on all the time you ride, and it will constantly make adjustments to the fuel trims. The one down side to this, is that if you use the auto-tuner in combination with the ECO mode on the 2010-2012 bikes, the auto-tuner will basically over-ride the ECO mode fuel trims and nullify the ECO mode. In this case, you would want to turn the auto-tuner off before using the ECO mode on the bike.

I'm wondering if pulling the flies on a C14 has less effect than it does on a ZX14 ??

I know when I pulled the flies on the ZX14 it made a huge difference down low, there was nothing subtle about the power it was in your face right off idle..  ;D

It's hard to say for sure without some quantitative testing. I've heard other ZX-14 owners say that removing the butterflies on the C14 and installing a Power Commander actually made MORE of a difference than it did on the ZX-14. But I haven't tried it myself, so I really can't say.
« Last Edit: April 24, 2012, 12:58:06 pm by Fred_Harmon_TX »
Fred H.


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