Thunder max popping at 1900-2500 rpm
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Joined: Apr 2007
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Module Maps and Settings to your ThunderMax ECM before ending the
Linked session.
value with a yellow background. This simply means that the value is on your computer,
but not updated to your ECM.
True, you do not need to clear the offsets. They have no bearing on the Basic Settings.
Quite possibly correct, the manual is rather unclear about this, but it never hurts to initialize and it may cause problems if you do not. As stated earlier; it's simple to perform the initialization process so why not do it an be safe? Just common sense.
Last edited by tckitt13; Oct 15, 2008 at 01:43 PM.
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Joined: Apr 2007
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Nevil, as per the manual your Basic Settings changes will not take effect until you Write them to the Module. That's the reason for the Write Settings to Module button on the page.
Again, the only changes that are "live" are the target afr or the timing adjustments that are made to the current map page while connected to the ecm. These changes are made to the ecm "live" but ARE NOT SAVED TO THE map UNLESS YOU SAVE THEM TO THE map. Or, since they are saved "live" to the ecm you could, as an alternative, read the map from the module again, read the offsets from the module again, and then save the opened (new and current) map and settings under a new file name.
Hope this helps.
Again, the only changes that are "live" are the target afr or the timing adjustments that are made to the current map page while connected to the ecm. These changes are made to the ecm "live" but ARE NOT SAVED TO THE map UNLESS YOU SAVE THEM TO THE map. Or, since they are saved "live" to the ecm you could, as an alternative, read the map from the module again, read the offsets from the module again, and then save the opened (new and current) map and settings under a new file name.
Hope this helps.
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Joined: Jul 2008
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From: southeast PA
They're starting on it maybe today, Friday at latest. He's real thorough and even has a high-powered magnifier thingy to check for cracks but I hope it will be simpler than that. I'm sure he's motivated to find the problem (besides the $) since he is of the mindset that the HD techs couldn't find their *** with both hands and a flashlight.
I definitely will let you know how it turns out since it could affect more of these bikes than we realize.
I definitely will let you know how it turns out since it could affect more of these bikes than we realize.
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What are you trying to fix? I assume that it's deceleration popping? Is the decel fuel cut enabled on your ecm? Where is the popping and what are the low and high fuel cut settings in the ecm?
I'll try to help if you need it.
I'll try to help if you need it.
Seasoned HDF Member
Joined: Jul 2008
Posts: 9,281
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From: southeast PA
It's decel pop with closed throttle while slowing to a stop. Also get a loud backfire either between shifts or just rolling off throttle at low to mid rpms. (It did this bone stock, adding slipons and Big Sucker magnified it.) I don't have a tach. Decel fuel cut is enabled. Low setting is 2016 and high is 2144, although there have been several variations. I've done several running logs and this is like the 5th map we've tried. The tech says AFR's are nearly perfect and the rest of the map is dead on, so the map seems to be right. That's why we're looking for a mechanical answer. Will be changing exhaust gaskets as well as looking for any intake or exhaust leaks.
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It does sound like an intake or exhaust leak. But the part that I don't understand is if there is a leak, it would seem that it would show up as a lean condition in the monitor logs???? Also seems like the T-Max would see a lean condition and try to compensate.
The fuel cut is usually quite a bit wider than the range you have now but you say you have tried several variations so they have probably addressed that. Example: mine is from 1988 to 2400 or so.
The intake leak would have to be after the throttle body...and the exhaust leak would have to be at or near the cylinders. I suspect that you and your mechanic already know this.
One other point that I don't know if anyone at T-Max has mentioned to you. If you get off the throttle but don't close the throttle completely you'll allow the bodies to open just enough to get the backfire. I know because I thought I was all the way off the throttle but found our I was actually holding the throttle just a hair off of fully closed. This is the same thing that happens if there isn't any play in the throttle cable...a dealer "adjusted" my throttle cable for me when doing other work and I didn't notice that all the slack was taken out until T-Max techs had me check.
Just out of curiousity...what are your AFRs running?
Good luck, TK
The fuel cut is usually quite a bit wider than the range you have now but you say you have tried several variations so they have probably addressed that. Example: mine is from 1988 to 2400 or so.
The intake leak would have to be after the throttle body...and the exhaust leak would have to be at or near the cylinders. I suspect that you and your mechanic already know this.
One other point that I don't know if anyone at T-Max has mentioned to you. If you get off the throttle but don't close the throttle completely you'll allow the bodies to open just enough to get the backfire. I know because I thought I was all the way off the throttle but found our I was actually holding the throttle just a hair off of fully closed. This is the same thing that happens if there isn't any play in the throttle cable...a dealer "adjusted" my throttle cable for me when doing other work and I didn't notice that all the slack was taken out until T-Max techs had me check.
Just out of curiousity...what are your AFRs running?
Good luck, TK
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Seasoned HDF Member
Joined: Jul 2008
Posts: 9,281
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From: southeast PA
I don't remember where the AFRs are now, don't know how to check without linking to the bike, but I think they were around 13.7. The Zipper tech told me to make sure the throttle was closed and not to "jack it around" once fully shut. I asked my indy to check throttle adjustment also, but it seemed to me to have enough slack.
Actually, the first tech at Zippers told me that my raw throttle position was off and I readjusted the throttle stop to get within range. The stop screw was not loctited or secured in any way, so it may have changed from the factory setting. He said there should be .0025 gap between the plate and throat, so I tried that and sent in a data module. That's when the current tuner got involved, said that I was misadvised and eventually we put it back closer to original setting, initialized and went from there. The tuner was ready to force fuel into the map at certain points but we'll wait until we get any findings from my indy.
I'm especially curious about the intake seals since the first dealer I took it to said they changed the seals even though nothing was wrong with them, and changed them out only because I told them my indy and 2 other people were convinced there was an intake leak. I have to wonder if they even checked.
The tuning guy is also trying to get me to pin down the speeds and conditions the problems occur at, and also whether it is a lean "crack" or a rich fuller pop.
Well, I just got a call from the indy and said everything was fine, found nothing and installed the new exhaust gaskets. Said it ran perfect. I'll let you know when I get it back, which will be soon.
Actually, the first tech at Zippers told me that my raw throttle position was off and I readjusted the throttle stop to get within range. The stop screw was not loctited or secured in any way, so it may have changed from the factory setting. He said there should be .0025 gap between the plate and throat, so I tried that and sent in a data module. That's when the current tuner got involved, said that I was misadvised and eventually we put it back closer to original setting, initialized and went from there. The tuner was ready to force fuel into the map at certain points but we'll wait until we get any findings from my indy.
I'm especially curious about the intake seals since the first dealer I took it to said they changed the seals even though nothing was wrong with them, and changed them out only because I told them my indy and 2 other people were convinced there was an intake leak. I have to wonder if they even checked.
The tuning guy is also trying to get me to pin down the speeds and conditions the problems occur at, and also whether it is a lean "crack" or a rich fuller pop.
Well, I just got a call from the indy and said everything was fine, found nothing and installed the new exhaust gaskets. Said it ran perfect. I'll let you know when I get it back, which will be soon.
Seasoned HDF Member
Joined: Jul 2008
Posts: 9,281
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From: southeast PA
Got it back. He checked injectors and seals, IAC seal, MAP sensor and seal, all intake seals, manifold body for cracks & integrity, throttle cables, changed exhaust gaskets. Pronounced everything in brand new shape. He was very impressed with how it ran compared to pre TMax. He said it runs great and what I'm hearing is normal, which is what everyone at HD says. (I just didn't believe them). He will be attending Zippers TMax training in the area and we'll talk after that.
I'll let my Zippers guy know this and see what he wants to do. At least I know there are no mechanical issues, and if this is the nature of the beast I will just have to live with it until we can tune it so it doesn't sound like a .38 caliber.
I appreciated your input and what you think about all this.
I'll let my Zippers guy know this and see what he wants to do. At least I know there are no mechanical issues, and if this is the nature of the beast I will just have to live with it until we can tune it so it doesn't sound like a .38 caliber.
I appreciated your input and what you think about all this.