2018+ Softail Models Breakout

Butt Dyno Wrong?

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Old Oct 19, 2019 | 04:46 PM
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Default Butt Dyno Wrong?

I just installed a DK587 AC on my FLDE. Besides this it is completely stock and run's great. It seems I hit higher speeds at lower rpms... and more spunky. Is it placibo effect? I don't know... but happy with the purchase and no symptoms of needing a tune as some suggested. Also it's nice now having a external breather on new bike. I will add new slip on and tuner when I get further into warranty. But good purchase imo
 
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Old Oct 19, 2019 | 06:57 PM
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Originally Posted by cj24
I just installed a DK587 AC on my FLDE. It seems I hit higher speeds at lower rpms
Impossible

Originally Posted by cj24
I just installed a DK587 AC on my FLDE. Besides this it is completely stock and run's great.... and more spunky. I don't know... but happy with the purchase and no symptoms of needing a tune as some suggested. Also it's nice now having a external breather on new bike. I will add new slip on and tuner when I get further into warranty. But good purchase imo
Yup, It probably runs a bit better.
 
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Old Oct 19, 2019 | 07:10 PM
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Yep I agree on the hitting higher speed's at lower rpms impossible lol. Maybe I'm just getting up to speed faster... or it running better just makes it seem so. At any rate happy with the purchase and install
 
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Old Oct 19, 2019 | 08:11 PM
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Honestly I find the butt dyno means a lot more to me than the paper type...

I’ve never ridden a piece of paper.
 
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Old Oct 19, 2019 | 10:22 PM
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Originally Posted by Thingfish
Honestly I find the butt dyno means a lot more to me than the paper type...I’ve never ridden a piece of paper.
The but dyno is easily fooled by changing the throttle progressivity table which the tuners do by default. It just commands the throttle plate to open more for a given amount of wrist twist. Makes the bike really seem quicker, however, more throttle is being used.

If tuning for power, the only known point to compare is running wide open. It is the only fixed reference throttle position that does not change. Always butt dyno test wide open. Maybe use one of those dragstrip dyno phone apps.

If tuning for driveability, it is possible for most riders to tell if the bike runs well or poorly.
 
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Old Oct 19, 2019 | 11:10 PM
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Originally Posted by Thingfish
Honestly I find the butt dyno means a lot more to me than the paper type...

I’ve never ridden a piece of paper.
As long as the engine is running in good order, I’m totally with you brother.
 
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Old Oct 20, 2019 | 12:13 PM
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Butt dyno has more than the butt as input. That intake honk for the new air cleaner certainly does improve the experience. And folks (well, at least I...) seem to spend more time just twisting the throttle to feel/hear the big performance gains from whatever doodad we just installed (air cleaner, exhaust, cam....). We're riding more aggressively and it just feels like something must be better, and if you're enjoying it, it's all good.
 
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Old Oct 21, 2019 | 06:52 PM
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My experience with butt dynos is that it register what it hope for, not what we actually have.

Paul
 
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Old Oct 21, 2019 | 07:18 PM
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Originally Posted by pondscum
My experience with butt dynos is that it register what it hope for, not what we actually have.

Paul
I agree they can be optimistic when it comes to number values, but I find they interpret how much the bike is to ride very accurately.
 
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Old Oct 21, 2019 | 08:57 PM
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Sorry I don't understand. "How much" what???

Paul
 
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