Lopey idle - Catless mid pipe

Agodnamedsin

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Howdy everyone,

First off I’d like to lead by saying, I’m sorry for re opening the long debate and conversation that’s happened on multiple threads. I suppose I just need some answers, answered differently? I’m nothing short of new to motorcycling, so sorry if these questions are repetitive or typically common sense. Trying to become more technical everyday.

2008 Yamaha Fz6 (S2)

This weekend I installed a cat-less mid pipe. I previously was already running two brothers slip-ons and decided to pull the trigger and go straight pipe (well except the cats in the headers). I’m now experiencing a lopey idle.

The lope isn’t fluctuating super hard, generally seeming to still sit around 1000-1100 rpm’s. I took her out for a ride and didn’t notice any worse performance, just a choppy idle. As much as the sound is to die for, I’m definitely running lean. No stalling either.

Video of idle:
So questions:

1. I’m obviously going to need a power commander to re-map the fuel map. I’ve seen to avoid the EX models as they can’t adjust lower rpm levels. Do I go PC3 or PC6 as PC5 was discontinued?

2. I noticed a lot of talk about throttle bottle synchronization, is this something I will need to do alongside the remap with a PC?

3. I seem to be confused on how the bikes are mapped and tuned. If I’m simply remapping the air to fuel mix, do I need to get it dynod? Is the dyno just used to specific tune to the specs of your bike?

4. I noticed everyone mentioning that resetting the battery with help flash the ECU to adjust to the new air to fuel mix on its own, but can anyone explain why the fz6 can do this? I was given ALOT of shit bike the community with them making fun and saying that simply isn’t possible as the ECU doesn’t get “wiped”. Just feel dumb for looking like an idiot.

5. I plan to also eventually down the line, advance the timing gear and get a healtech quick shifter. Will I need to additionally tune the bike after these?

6. Last but not least, will running my bike like this for the rest of the month cause any sort of harm or damage I should be aware of?
 

Motogiro

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Talking about fuel management is more complex than we might think. As far as resetting (not flashing) the ECU: I don't remember exactly what I did once on my FZ6 but the Air to fuel mixture when wacky making the bike run rough and blowing black smoke. I tried shutting it off and restarting but it was not good. I disconnected the battery for 30 minutes and reconnected the battery and it ran fine ever since. So there is what I believe is volatile memory with the ECU where it can relearn and store small adjustments This could be more the case with the S2 models that have an O2 sensor. Although I can"t say for sure There may be a small learning curve for the ECU. When you install a Two Brothers exhaust they do say disconnect the battery. I don;t know if it more for safety or for volatile memory reset.

The area of larger impact would be a fuel management device. You may find a map with like components for another bike that could be better than a stock map but to be truthful it's probably better to do the fuel management with the dyno or just leave the bike and maybe do the CO tweaks. Again doing the CO tweaks with out a sniffer is another guessing game. You want to know your A/F ratio.

Pulling the CAT with the reduced back back pressure that the Twos Bro's give you puts you in a possible lean scenario. Maybe put the CAT back.

I had my bike dyno tuned by a reputable tuner. The honest gain in horsepower was not that much for the total of hundreds spent on the a PC and the dyno but the bike was so much fun when I took it for spirited runs and I don't regret doing it the right way.
So yes some fuel management devices do nothing at the lower RPM to meet emissions and some are for track only application where they are not for street application.

There's nothing wrong with being enthusiastic about your bike but it generally takes some thought and $$$.
The main thing is to invest in good protective gear and hone your skills and experience to ride as long as you can enjoying the great experience of riding.
 

Agodnamedsin

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Talking about fuel management is more complex than we might think. As far as resetting (not flashing) the ECU: I don't remember exactly what I did once on my FZ6 but the Air to fuel mixture when wacky making the bike run rough and blowing black smoke. I tried shutting it off and restarting but it was not good. I disconnected the battery for 30 minutes and reconnected the battery and it ran fine ever since. So there is what I believe is volatile memory with the ECU where it can relearn and store small adjustments This could be more the case with the S2 models that have an O2 sensor. Although I can"t say for sure There may be a small learning curve for the ECU. When you install a Two Brothers exhaust they do say disconnect the battery. I don;t know if it more for safety or for volatile memory reset.

The area of larger impact would be a fuel management device. You may find a map with like components for another bike that could be better than a stock map but to be truthful it's probably better to do the fuel management with the dyno or just leave the bike and maybe do the CO tweaks. Again doing the CO tweaks with out a sniffer is another guessing game. You want to know your A/F ratio.

Pulling the CAT with the reduced back back pressure that the Twos Bro's give you puts you in a possible lean scenario. Maybe put the CAT back.

I had my bike dyno tuned by a reputable tuner. The honest gain in horsepower was not that much for the total of hundreds spent on the a PC and the dyno but the bike was so much fun when I took it for spirited runs and I don't regret doing it the right way.
So yes some fuel management devices do nothing at the lower RPM to meet emissions and some are for track only application where they are not for street application.

There's nothing wrong with being enthusiastic about your bike but it generally takes some thought and $$$.
The main thing is to invest in good protective gear and hone your skills and experience to ride as long as you can enjoying the great experience of riding.
I debated playing the CO game and trying to dabble into messing with the onboard system myself but without the sniffer I don’t plan to attempt it. I was hoping I’d find somebody in a similar boat where they had after market cans and the catless mid pipe and adjust the CO enough to correct the lope but I’ve had no luck.

There’s definitely already more back pressure with the two bros but significantly more without the cat. I fear that this may ultimately be the solution I have to go back to but I really really want to attempt to succeed on this project. At what point would my bike be indicating it’s far too lean or is potentially damaging my bike?

I’ve found a rather reputable tuner in the city close by to me with lots of refs. I’m honestly willing to pay the money (whether compared to other bikes the money to power ratio may be wayyyyy off). I expect no more then like a 7hp gain from it in total but I plan to keep this thing for a longggggg time. I definitely would like to go the same route and do this the right way. What PC or fuel controller did you end up mapping with?

I appreciate every bit of information you shared. Already made sure I have a helmet, boots, perf gear for the summer and a full leather suit just because. I’m all geared up every ride.
 
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