Honda VTX Forum banner

1 - 20 of 41 Posts

·
Registered
Joined
·
37 Posts
Discussion Starter #1
I do not recall seeing a post that talks about anyone switching from a PC3 to a Cobra. I am wondering if someone has and if it worked to help rid of the decel pop? I currently run the PC3 (came with bike when I bought it). I did all the mods from bareasschoppers that should rid the decel popping but it did not help. I have a CA model 1800S2 and have gone back and verified all of the procedures that I did. did the exhaust crush washers twice to make sure that I didnt screw them up the first time (yes, I know I could have screwed them up twice). The decel pop is my only complaint as she starts up and runs good minus that annoyance. I do not have access to a dyno around here to have it checked and have the PC3 mapped. I have looked at the maps that are out there (bareasschoppers) to verify it has the correct map but do not see the exhaust that I am running . Running 3inch Hard Krome long pipes, but besides that, it is stock. I have a feeling it isnt mapped correctly?
Does anyone have any idea if I could just take off the PC3 and put the Cobra Fi2000 powerPro or the lesser expensive Fi2000R on or would that just be a huge mess? I dont know if it would be as simple as taking the PC3 off and putting the Cobra on and driving it a couple blocks type deal (Yes, I know that would be to easy but thought I would ask). Just not sure if anyone has already done it? Thank you in advance.
 

·
Super Moderator
Joined
·
63,684 Posts
Try here for more maps and locations of dyno shops
www.powercommander.com

Going from a PC3 to a Cobra would be a downgrade as you would only be using 1/3rd of the Cobra unit to stop the popping. You'd set it at 2-0-0 and if it still popped you bump up the first pot. Or, you could YouTube on how to use the PC3 and do the same thing, bump up the lower RPM range some to stop the popping
 

·
Premium Member
Joined
·
6,541 Posts
Right on Spike. The PC3 has all of the functionality of the FI2000R and then some. You can put a stock tune (a zero map) into your PC3 and use the 3 buttons on the front to do exactly what the FI2000R does.

The FI2000 PowerPro is a bit different. It tunes as you ride. Here's a description of how it functions;
I don't know it does much for decel pop though. The Harley owners that use it generally like it.
 

·
Registered
Joined
·
37 Posts
Discussion Starter #4
Thank you. Looks like I need to start watching some you tube videos! If I read correctly on the pc3, if I unplugged it, the bike would just go back to stock without doing anything else. Reading many posts on this site, there are a ton of people who use these and just as many that dont. I'm not looking for hp. I'm looking to not have decel pop and a good running bike. Thoughts on just unplugging it and seeing how the bike runs stock first then if no change for the better, plug her back in and start trying to manually tune it? Either way, thanks for the tips on the videos as I was under the impression these had to have a map specifically for each bike and not knowing who origanally put it on and doubting they put it on a dyno makes me wonder id just taking it off would be ok.
 

·
Registered
Joined
·
319 Posts
I would unplug it see how you like it. Usually the maps you get are leaner because they make more power which causes more popping. If you are running straight pipes its really hard to get rid of decel popping on these bikes. A couple things to try ride in a higher gear when you are slowing down, also try slowing down the throttle close on decel. I found on mine that a small amount of back pressure really helps
 

·
Registered
Joined
·
1,890 Posts
I went from the PC3 to the Powrpro when they were first introduced and am very satisfied. No decel popping and the power is very linear. Before you put out the big bucks try adjusting your PC3 yourself. Look only at the "zero" throttle column starting at 1500 RPM up to redline and change the numbers to 30. When you are riding and go to slow down or stop get off the throttle completely, don't trail the throttle.
 

·
Registered
Joined
·
37 Posts
Discussion Starter #7
Thanks for ththe replys. You mentioned you switched. Could the PC3 just not manually tune enough for you so you went with the Cobra? I do like the fact that the PC3 can be adjusted so I will absolutely try that before dropping 400+ on a Cobra. Just hoping I can get it adjusted enough. Appreciate everybody's input that has given.
 

·
Registered
Joined
·
1,890 Posts
Thanks for ththe replys. You mentioned you switched. Could the PC3 just not manually tune enough for you so you went with the Cobra? I do like the fact that the PC3 can be adjusted so I will absolutely try that before dropping 400+ on a Cobra. Just hoping I can get it adjusted enough. Appreciate everybody's input that has given.
My PC3 was getting long in the tooth as the unit was on the bike when I bought it back in '08. I was getting the decel popping back slowly but surely. I would jack up the rich settings in zero throttle a little and it would disappear but only for a while. I switched to the Cobra in July '12 and it's still doing it's job. By the way, forgot to ask, did you remove the PAIR reed valves and replace with blank plates?
 

·
Registered
Joined
·
37 Posts
Discussion Starter #9
I did do the PAIR red valves blank off plates. Desmoged her and two weeks ago went back and re-sealed the plates just to verify I had enough hi-temp rvt on those. I read someone on here had decel pop after they did the desmog and that was why they still had it so i thought i would go back and verify i had sealed them good. I had also purchased baffles after I first bought it as the guy I bought it from had taken them out. Wanted to make sure it had the back pressure it should.
 

·
Registered
Joined
·
1,890 Posts
Sounds like everything is covered. Look forward to hearing how the change in the PC3 map goes. If it works for you then start to bring the numbers down from 30 until the popping returns. Then notch it up a couple of numbers. I was running for a long time at 15 before the PC started to drift.
 

·
Registered
Joined
·
37 Posts
Discussion Starter #11
Sounds like everything is covered. Look forward to hearing how the change in the PC3 map goes. If it works for you then start to bring the numbers down from 30 until the popping returns. Then notch it up a couple of numbers. I was running for a long time at 15 before the PC started to drift.
Now I am a bit confused to your 15 and 30 referance. Spike mentioned a 2-0-0 which I am relating to how many light bars above the 0 line. (Low button gets 2 lights above 0, mid stays at 0, and high stays at 0).Unsure of wat you're referance of 15 and 30 is coming from? The dyno jet site says to start the bike while holding all three buttons down to make the adjustments while the YouTube vids say just turn the ignition on to get power to the commander.
 

·
Registered
Joined
·
1,890 Posts
Sorry, I assumed you have the PC3 USB unit. If you do then you can connect your laptop to your PC3 and download maps as well as adjust the map that's already in use. Check which unit you have first, then if you have the USB unit go to the Dynojet Power Commander website and download the app. for the PC3 onto your computer. They also provide tutorials on how to adjust or replace your map.
 

·
Premium Member
Joined
·
6,541 Posts
Now I am a bit confused to your 15 and 30 referance. Spike mentioned a 2-0-0 which I am relating to how many light bars above the 0 line. (Low button gets 2 lights above 0, mid stays at 0, and high stays at 0).Unsure of wat you're referance of 15 and 30 is coming from? The dyno jet site says to start the bike while holding all three buttons down to make the adjustments while the YouTube vids say just turn the ignition on to get power to the commander.
When Spike said 2-0-0 he was referring to the settings on a Cobra FI2000 or FI2000R. You can get the same result from your PC3 but the numbers mean different things on different devices.
 

·
Registered
Joined
·
37 Posts
Discussion Starter #14
Got ya. Sojourner, I do have the PC3 USB. That makes more sense now. Harkon, I get it from your side as well. That also makes sense. I do believe I have another issue as I was messing with it. A seriously pinched cord. I actually took the low rpm button and adjusted it to the top of its range (highest light it would go). All three rpm buttons were at the positive 2 light (second one from the zero, or double lights). There was no change at all. I then took all of them and moved them all to zero and no change at all. I can twist the throttle and see the light move up and down when I do that. So it is at least reading that throttle movement. My thought is that it isnt working. At least not correctly as I would think there may be a broken wire where it was pinched. Will need to start researching that part of this puzzle.....Let the fun continue 😮(y)
 

·
Premium Member
Joined
·
6,541 Posts
Good luck. The object here is to do one of 2 things. Either cut the fuel entirely on decel so you get no unburned fuel in the exhaust pipe ... nothing to pop. OR, on decel create an overly rich condition so that the unburned fuel in the exhaust is so rich it cannot ignite. You need two things to get decel pop. Unburned fuel an air. If you're getting air into the exhaust, think exhaust leak here, on decel the exhaust will pull in fresh air and you'll get popping to the degree you get air into the system. More air, more popping. Kn that case you'll need to find out where the air is getting in, and fix that first. Most commonly this is at the exhaust port gasket.

The FI2000 (not the PowerPro) can only add fuel, so there's only one way to go there. That's where the 2-0-0 settings come from. These bikes run pretty rich at larger throttle openings and higher RPM, and really lean down low ... EPA emissions standards.

You mention you have a CA bike. Is the O2 sensor still in place? If it is, you'll need to get an O2 eliminator and unplug the sensor, otherwise what you do with the PC3 is corrected for by the O2 sensor and the ECU. The net result is that the PC3 does very little.

I cannot stress this enough. No matter what you do, you will have a tough time eliminating pop unless you do a very thorough ground fix. That includes removing paint where it's recommended you remove paint. A half assed approach on this nets half assed results ;)
 

·
Registered
Joined
·
37 Posts
Discussion Starter #16
I do not know if the O2 sensor is still in place. I would assume it is. This bike did not have any desmog done to it before I bought it. I did the desmog (from bareasschoppers website) I did see that part that talked about the little soup can removal and the other parts on the California bikes and I took care of that. I also did do a thourough job ( at least I think I did :)) of doing the ground mod. Got the dremel out and did paint removal where it was needed/recommended. I will now also need to see where the O2 sensor is and get an eliminater for that. I have not heard about that part so that is new to me. Time to google that part #?
 

·
Premium Member
Joined
·
6,541 Posts
I do not know if the O2 sensor is still in place. I would assume it is. This bike did not have any desmog done to it before I bought it. I did the desmog (from bareasschoppers website) I did see that part that talked about the little soup can removal and the other parts on the California bikes and I took care of that. I also did do a thourough job ( at least I think I did :)) of doing the ground mod. Got the dremel out and did paint removal where it was needed/recommended. I will now also need to see where the O2 sensor is and get an eliminater for that. I have not heard about that part so that is new to me. Time to google that part #?
Basically the O2 sensor eliminator will set up a small resistor network (voltage divider) that lies to the ECU and tells it the exhaust is not too rich or too lean. The ECU can run on a base map and any changes the PC3 makes will be added or subtracted from the ECU base map. The ECU then doesn't correct the changes the PC3 makes to the fueling. If you just unplug the O2 sensor, the ECU will throw a code, because it needs some sort of feedback, even it it's being lied to. Your R should have 2 O2 sensors, one for the front and one for the rear cylinders.
 

·
Registered
Joined
·
37 Posts
Discussion Starter #19
Awesome explanation. Even an old dumb guy like me could understand that. Thank you for taking the time to explain that. Do I remember correctly that the R model and the S model are the same then?
 

·
Registered
Joined
·
37 Posts
Discussion Starter #20
Thank you for the recommendation Sojourner. Should see those in a few days. Gives me times to do ore research and burn some more fuel out of the tank so by the time they come in, I will be able to get the tank off without the dreaded fuel spillage. Thanks again gents and I will post as I go to see how the saga goes...
 
1 - 20 of 41 Posts
Top