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Dyno tuned and decel pops

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Old Dec 12, 2018 | 07:45 AM
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Default Dyno tuned and decel pops

Hey guys,
Just got bike tuned and it it runs smoother, better throttle response and I feel it pulls stronger. I originally had an SE tune from dealer and it ran good but now its more noticeable. Another thing that is noticeable is that the decel pops are more apparent, if its a high decel or coming off freeway. Usually around 2000 rpm. If im riding normal and not on it, decel pops are minimal. I did have some decel pops with SE tuner and i thought a dyno tune would help but it didn't. I talked to dyno guy and he did not notice any during dyno testing and he was tuning for several hours under different loads. Not sure if these are normal considering its a hard decel from high rpm, or possibly even the rinehart slip on mufflers as they are more open and flow more. There are no exhaust leaks as that has been checked. Not sure if making changes will hinder some performance loss if adding/removing fuel. I was under the impression that decel pops are due to bad tunes but bike feels better... Any thoughts?

2018 Fat Bob 107 with stage 2 torque cam, se ventilator, rinehart slup ons and power commander v tuned.
 
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Old Dec 12, 2018 | 08:12 AM
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Was it dyno’d by a dealer tech? I’m just thinking a proper tune should eliminate decel pop, but I could be wrong
 
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Old Dec 12, 2018 | 08:17 AM
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I agree with purpledeuce. If it was tuned properly, I don't think you should be getting decel pops. I did a stage 2 on mine and it was popping like crazy. Had it dyno tuned and has not back fired once since.
 
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Old Dec 12, 2018 | 08:23 AM
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I did an all SE Stage 1 dyno tuned with the lowly SEPST and never a hint of decel popping ever..runs crisp, clean and smooth
 
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Old Dec 12, 2018 | 09:02 AM
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When they tune the put as much fuel into the tune as they can .So if you experience decal pop sometimes its ok but if its all of the time the bike has to much fuel going into it, I would take it back.
 
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Old Dec 12, 2018 | 09:17 AM
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It was done at a non harley shop. I was thinking the same thing but was just wondering if a tuned engine still decel pops because to eliminate that popping, you’ll have to accept the fact that your motor is going to be forced to run rich to do it, and that isn’t necessarily a good thing??
 
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Old Dec 12, 2018 | 09:35 AM
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Depends on the tuner you put on your bike and what you want out of it. Top end performance requires more fuel. I mean when you run high. Pushing hard, high speed, those require more fuel. So tuners will pump fuel into the tables for those higher areas. This means hot rodding will see pops when you let off. Running the interstate at high speed. If you ease off as you come to the off ramp it will be smooth, if you just hit the ramp and let go you will probably have some popping.

Your dyno tech can certainly adjust and eliminate the popping but it comes at the cost of top end performance usually. But again it depends on the tuner you have. As I understand it not all of them can be fine tuned the same.

It is a give and take. What do you want out of it? It is always best to have a discussion with your tech rather than just dropping it off.

My 08 got a 103 kit, intake, and SE slip ons from original owner. he just added a fuel pak. Ran fine for putting around the flatlands like an old dude with his wife. I wanted better. Got the SE tuner so we could adjust the actual computer and tables, changed exhaust. I have some popping but nothing horribly obnoxious. Coming off the interstate at 80 if I completely let off I will get a pop or two.
I know having it dyno'd isn't exactly cheap most of the time but being able to be there and talk to them about how you want it to perform is key. After all, it is a computer and we can make them do whatever except your idea of correct probably differs from what the tech thinks.

My .02
 
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Old Dec 12, 2018 | 09:51 AM
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Usually if you add a little fuel to that 20 MAP column it will take it all out of decel.
 
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Old Dec 12, 2018 | 09:59 AM
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you could also post in the Tech Forum The Dyno Room Ignition/Tuner/ECM/Fuel Injection and hopefully the subject matter experts will chime in
 
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Old Dec 12, 2018 | 10:28 AM
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Can you post a before and after Dyno chart?
 
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