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Author [ES] [MY] [PL] [PT] [IT] [DE] [FR] [NL] [DK] [NO] [GR] [TR] Topic: Full aftermarket exhaust system - bogging down on acceleration - fix?  (Read 862 times)

zoid, RobZ900, gary and 9 Guests are viewing this topic.

Offline dhz900

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Installed a full Delkevic exhaust on my 2020, and noticed a odd issue on 1st and 2nd gear.

When i'm under heavy acceleration (80-100% throttle) in gears 1-3 (mostly 1/2) the bike is bogging down which I'm almost positive it's to do with the air fuel ratio. It's really hit the performance in low gears.

I'm trying to figure out, is it too lean (betting on this) or too rich? The bike only has 500 mi so it can't be the air filter. Anyone recommend a Powercommander over a reflash? I like the idea of being able to actually adjust my system more than once if I used a power commander. I've only ever used a powervision for a Harley and it worked great, but i've never toyed with PC5.

Suggestions please.

Online RobZ900

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Seems to be a common theme emerging on the forum over the last few days with similar questions popping up. On the 2017-19 model, exhaust manufacturers stated that a time wasnt necessary with a set of headers. This is due to the 17-19 model running rich from factory, so adding a full system actuall brought the air/fuel closer to what it should be. However, for the 2020 model, dont know about other manufacturers, but Akrapovic recommend a tune if you fit the headers. Guessing that the new model has different mapping due to the rider modes etc, so youre probably right about it screwing up the air/fuel. Power commander or an ECU tune will sort that problem out. Got no recommendations, but personally Im going with a tune.
Motorcyclist - noun (moh-ter-sahy-klist)
: a person willing to take a container full of flammable liquid, place it on top of a hot, moving engine and then put the whole lot between their legs!

Offline RR

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2 Wheel DynoWorks made a nice blog on their website a few weeks ago. Not entirely independent, but their explanation sounds reasonable.

https://2wheeldynoworks.com/why-is-ecu-flashing-better/

Offline ksimon

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*Originally Posted by dhz900 [+]
Installed a full Delkevic exhaust on my 2020, and noticed a odd issue on 1st and 2nd gear.

When i'm under heavy acceleration (80-100% throttle) in gears 1-3 (mostly 1/2) the bike is bogging down which I'm almost positive it's to do with the air fuel ratio. It's really hit the performance in low gears.

I'm trying to figure out, is it too lean (betting on this) or too rich? The bike only has 500 mi so it can't be the air filter. Anyone recommend a Powercommander over a reflash? I like the idea of being able to actually adjust my system more than once if I used a power commander. I've only ever used a powervision for a Harley and it worked great, but i've never toyed with PC5.

Suggestions please.

I noticed the same issue with my full exhaust, I played around with my power commander ratios and made no difference, but I found that if you enable the accel Dump on the power commander  it completely resolved the stumble on quick throttle turn. But I am sure a reflash should fix it also.

Offline dhz900

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*Originally Posted by ksimon [+]
I noticed the same issue with my full exhaust, I played around with my power commander ratios and made no difference, but I found that if you enable the accel Dump on the power commander  it completely resolved the stumble on quick throttle turn. But I am sure a reflash should fix it also.

So would you reccommend the PC5? I don't really like the reflash option (simply because this is the 5th bike i've had in 2 years and I don't need MAX performance), and I'd like to remove the PC5 for a future bike (i'm pretty sure you can do this with PCV?) Kinda sucks to spend 320 ish dollars just to disable a accel dump.

After further research i've come to find the same situation arises with other 2020's, i'm just trying to figure out what makes the most sense for me. I see PC has 2 full exhaust tunes (akra and Leovince, I assume with my full delkevic exhaust it'd closer resemble full akra) Again, not going for maximal performance, but I want the bike to sound louder and run like it did at stock.

Leaning towards PC5...

Offline Cazzy_R

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*Originally Posted by dhz900 [+]
Leaning towards PC5...

I am surprised to see DynoJet are advertising the same maps for the 2020 model as they are for the 2017-19 models.  :027:
Cazzy_R

Tighten it 'til it strips then back it off half a turn.

Offline dhz900

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*Originally Posted by Cazzy_R [+]
I am surprised to see DynoJet are advertising the same maps for the 2020 model as they are for the 2017-19 models.  :027:

I get why you would say that, however, if it's the same system then the same map would be used, as it's the same adjustments/set point(s).

Online RobZ900

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*Originally Posted by dhz900 [+]
I get why you would say that, however, if it's the same system then the same map would be used, as it's the same adjustments/set point(s).

I dont see how that can work. Clearly the 2020 model runs a different stock map than the 17-19 models do. A power commander simply adds extra fuel where needed and takes it away where the stock map is too rich. If the fuel mapping is different between the 2 models, then the map for the 17-19 model would be adjusting the fuel in the wrong areas for the 2020 model.
Motorcyclist - noun (moh-ter-sahy-klist)
: a person willing to take a container full of flammable liquid, place it on top of a hot, moving engine and then put the whole lot between their legs!

Offline Cazzy_R

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*Originally Posted by dhz900 [+]
I get why you would say that, however, if it's the same system then the same map would be used, as it's the same adjustments/set point(s).

 I guess if all the original set point values in the 2020 ECU are the same as the 2017-19 that would be right.
Cazzy_R

Tighten it 'til it strips then back it off half a turn.

Online RobZ900

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*Originally Posted by Cazzy_R [+]
I guess if all the original set point values in the 2020 ECU are the same as the 2017-19 that would be right.

Thats the point Im making though, how can they be the same? The 2020 model has got different fuel maps for rider modes and if that wasnt enough, the exhaust manufacturers state that no mapping is needed for the 17-19 model but is for the 2020 model. Clearly the stock map is different between the two, so how can a map that works for one be correct for the other?
Motorcyclist - noun (moh-ter-sahy-klist)
: a person willing to take a container full of flammable liquid, place it on top of a hot, moving engine and then put the whole lot between their legs!