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bought 07 road king new,after break in miles put high flow air clean and Samson fishtail slip ons no baffles,installed PC111 picked closest map on list ran great ten years,. end of 2017 PC111 took a crap early 2018 season put PCV on picked a map ran good with occasional popping from 1st to 2nd . this year seems to be running hot and almost continually popping when let off throttle and shift, tried few diff maps not much difference . went back to first map and added 15 in 0%throttle from 2000 -6500 rpm,now some rides its ok then others not so much.Any suggestions on what might be going on ? And whats your feelings on the add on auto tuner for the PCV. Thanks for and help that someone can give
 

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not sober all the time
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Good luck on eliminating decel pop without baffles. Tuning helps but without baffles it's a challenge. Normal stuff to check includes intake/exhaust leaks. Don't have any experience with auto tuning.
 

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Not sure what a PCV will let you do as far a decel fuel mapping.

But you have two ways to address it. Add fuel so that its too rich to pop. That's what most tunes/tuners do. Its 90%ish effective, but does leave a lot of black soot on the cans.

The better way of doing it is to turn the fuel off during decel. But then you'll need to work on the throttle roll on anticipation setting, or it will hesitate. This way works better, but can take a few trips to the software to sort it out.
 

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I run a PCV and never had a single decel pop.
But I didn't just load a map and hope for the best.
My bike had some runs on a dynojet bank to set the PCV
 

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Popping is unburned fuel that detonates inside the the hot exhaust on its way out.
I dont see the difference between open fishtails or the 'look through' baffles on my V&H ovals. The only thing those baffles do is kill the high tones and pass the low tones.
My point of view, even with open fishtail of dragpipes, with a proper tune you will not get popping.
 

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Second, unburned fuel that passes the hot exhaust also needs oxygen to detonatie.
Think about reverse puls or leaking gaskets to archieve that
 

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I run a PCV and never had a single decel pop.
But I didn't just load a map and hope for the best.
My bike had some runs on a dynojet bank to set the PCV
What's the difference between a dyno tune and just changing the fuel numbers at 0% throttle? On decel, you aren't really targeting any AFR so how does the dyno help at closed throttle?

Answer: you paid someone else to change the numbers in your map.
 

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Discussion Starter #10
found rear manifold at crossover pipe is cracked thanks for pointing me in right direction. this is probably why I didnt have many issues in past, must have cracked recently. harley parts guy says this happens often in that spot.$400....I will pull it and weld
 

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I dont have a calibrated wide band AFR gauge, and the easiest way to get it right is a trip to the dynojet. You can not guess the AFR.
That's the difference between a dyno tune or just changing the fuel numbers jourself.
The PCV owns a nice option, you can connect a switch and run 2 maps. Toggle it to change maps on the fly. So I copied the base dynojet map and set it on place 2 to experiment. Sometime things get wrong, no problem flip the switch and get home safe.
I did need it once almost crashed...
There is a lot going on at the ECM there are more fuel/ignition tables in there then most can imagine.The PCV is a piggyback module to add some more or less fuell at a given throttle/rpm range and ignition settings. Just use it to get out of the lean conditions, nothing more.
There is an ECM start table, noticed the big bang at every start? That's some extra fuel to start, a table that wil look at cranking RPM and temp and inject an extra ammount of fuell. Never tried it but you can probably mess it up too with PCV and very low rpm fuel settings.
As experiment I did try to lower idle rpm. Easy I thought just put less fuel in there and mess some with ignition and rpm's will drop.
It worked for half a second. The ECM says, wait it is cold go to 1500 rpm, no says the PCV you dont get fuel and rpm drops. But then the ECM kicks back in, says hold you are to slow here is some more fuel.
And on and on... Trying to lower Idle with PCV will result in a jumping tach needle from 900 to 1500.
But there are also decel tables at the ECM. It did scare me.
Close the throttle and most of us think, ok this is 0. It is not and things go wrong when you mess up the PCV
Running on the highway I closed the throttle but it went on and on. Had to hit the brakes hard lucky I have ABS. The ECM has nothing to blaim it does a perfect job. The ECM decel table will not completely shut down the fuel with 0 trottle, but to a certain ammount to archieve decent engine brake. There was no engine brake, a table cell at the PCV sayd, hold it you are at 4000 rpm here is some extra fuel, and while we are here, lets adjust some timing too...
And a day later with the same experimental adjustments, I had the opposite on lower rpm's. Cold engine, start driving and got up to 50 km/hr. Let go the gas and it locks the rear wheel due to heavy engine braking. Again the decel table is there not to complete shut down the fuel, It will hold some rpm (and fuel) to an ammount acceptable for engine braking. To little the rear wheel will block, to much it will get no engine braking at all. You can **** it up with a PCV like I did, but lucky, toggle the switch to the main map and your good to go.
Ok long story back to the subject. Its not about 0 throttle to get 0 fuel and no decel pop.
Then something other comes to my mind. A tuner once told me: I cant messure your o2 at the exaust tip there is a cat in front of it, it will eat my o2. Ok that's maybe another reason why I never ever heard a single decel pop, there is simple no oxigen inside my exhaust to detonate anything
 

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I dont have a calibrated wide band AFR gauge, and the easiest way to get it right is a trip to the dynojet. You can not guess the AFR.
That's the difference between a dyno tune or just changing the fuel numbers jourself.
The PCV owns a nice option, you can connect a switch and run 2 maps. Toggle it to change maps on the fly. So I copied the base dynojet map and set it on place 2 to experiment. Sometime things get wrong, no problem flip the switch and get home safe.
I did need it once almost crashed...
There is a lot going on at the ECM there are more fuel/ignition tables in there then most can imagine.The PCV is a piggyback module to add some more or less fuell at a given throttle/rpm range and ignition settings. Just use it to get out of the lean conditions, nothing more.
There is an ECM start table, noticed the big bang at every start? That's some extra fuel to start, a table that wil look at cranking RPM and temp and inject an extra ammount of fuell. Never tried it but you can probably mess it up too with PCV and very low rpm fuel settings.
As experiment I did try to lower idle rpm. Easy I thought just put less fuel in there and mess some with ignition and rpm's will drop.
It worked for half a second. The ECM says, wait it is cold go to 1500 rpm, no says the PCV you dont get fuel and rpm drops. But then the ECM kicks back in, says hold you are to slow here is some more fuel.
And on and on... Trying to lower Idle with PCV will result in a jumping tach needle from 900 to 1500.
But there are also decel tables at the ECM. It did scare me.
Close the throttle and most of us think, ok this is 0. It is not and things go wrong when you mess up the PCV
Running on the highway I closed the throttle but it went on and on. Had to hit the brakes hard lucky I have ABS. The ECM has nothing to blaim it does a perfect job. The ECM decel table will not completely shut down the fuel with 0 trottle, but to a certain ammount to archieve decent engine brake. There was no engine brake, a table cell at the PCV sayd, hold it you are at 4000 rpm here is some extra fuel, and while we are here, lets adjust some timing too...
And a day later with the same experimental adjustments, I had the opposite on lower rpm's. Cold engine, start driving and got up to 50 km/hr. Let go the gas and it locks the rear wheel due to heavy engine braking. Again the decel table is there not to complete shut down the fuel, It will hold some rpm (and fuel) to an ammount acceptable for engine braking. To little the rear wheel will block, to much it will get no engine braking at all. You can **** it up with a PCV like I did, but lucky, toggle the switch to the main map and your good to go.
Ok long story back to the subject. Its not about 0 throttle to get 0 fuel and no decel pop.
Then something other comes to my mind. A tuner once told me: I cant messure your o2 at the exaust tip there is a cat in front of it, it will eat my o2. Ok that's maybe another reason why I never ever heard a single decel pop, there is simple no oxigen inside my exhaust to detonate anything
Well, I didn't understand any of that, but the point still remains, there is no "proper AFR" for decel. It's trial and error, whether on a dyno or not.
 

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I had the same problem and trouble shooting experience on my 2011 RK after I installed an SE Stage III Big Bore kit. I tried everything. The dealer insisted that I get a $375 SE Race Tuner and a $400 Dyno tune. I did but that did nothing. So I contacted Dynojet and the tech had me add fuel at several RPM points below 1,500. Well thanks to Dynojet my decel popping nearly disappeared. So I wasted $750 on stuff I didn't need.
Call Dynojet or send them a portal message.
 

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If it pops the moment you begin closing the throttle the solution is changing the decel enleanment multiplier. If the popping starts when the throttle is nearing 0% on the TPS you'll want to bump the VE slightly in the 0% and 2% columns as well as adding ignition advance. Or in my case I had to do both. Dynojet has a video on their site explaining Decel Pop solutions. (it doesn't cover enleanment though) 2016 FXDB with V&H mini grenades with a case of machine gun pops anytime you closed the throttle . Now completely eliminated with VE tables +2.5 in 0% column (1750 RPM and higher) and plus 1 in the 2% column (2,000RPM and higher) . Ignition Timing +3 Degrees advance in the first two columns 1500RPM and higher. Global Deceleration Enleanment Multiplier changed from 1.0 to .90 . These settings are for Power Vision so not sure how they would translate to Power Commander but hopefully this will help someone. On a side note , I originally went with the full 20 bump in the VE tables that Dynojet suggests and ended up leaning it back until I arrived at these figures. At 20 that FXDB sound like a slushy machine when you'd let off the throttle hahaha
 
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