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Thunder Max problems!

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Old Aug 13, 2008 | 02:19 PM
  #1  
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Default Thunder Max problems!

Thought a few of you would like to know my experience with the Thunder Max with Auto Tuner.
I’ve had this in my 2007 FLSTC for around 4500 miles with no problems. The bike seemed to run strong and I was overall pleased with its performance. Although I did seem to have a dead spot in my throttle once and a while and seemed to have more valve ping than normal. I did recheck the base map twice.
During my trip to Sturgis I had problems with it. The fuel pump initiation circuit became undependable. I drove it from Rapid City to Spearfish where we were staying Tuesday night. Wednesday morning I got up and went to start my bike and it would turn over and all acted normal however the fuel pump wouldn’t start. I traced it out to the Thunder Max module. After about two hours of testing it started working then it would quit then work and so on. I tried doing to reinitiaion procdure twice with no luck. I had my Harley computer sent to me next day air and it started up and I managed to ride it home with the broad band O2 sensors in it. I haven't had any problems after going back to the Harley module. I lost one day due to this problem. I’m going to send it back to Thunder Max and see what they have to say. I’ll keep you guys posted on the outcome.
 
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Old Aug 13, 2008 | 02:46 PM
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Zippers seems to have some reliability problems with their Thundermax unit. I could just be that people that replace their ecms are more likely to post about problems. Still, the idea of having my bike die out on the road due to the ecm failing gives me the *******. It seems, if nothing else, they need to implement limp home mode to at least get you to the next major town as opposed to push it, leave it or tow it.
 
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Old Aug 13, 2008 | 03:20 PM
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I had the same concerns about the TMAT, being left stranded on the side of the road because of a computer glitch or sensor failure and not having any backup. I went with it anyway and am fortunate to say I haven't had any problems so far after 10k. Even went to Sturgis with it then down around through Co. winding my way back to central Tx. Did Pikes Peak late last year with it too, no problems. My bike runs great with it, i'm a happy camper.
 
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Old Aug 13, 2008 | 04:07 PM
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Default Problems

I have the thundermax. one day the engine lite started to flash with about 200 miles on bike and 10 miles on max. the max had the right map in it. Rode the sholder b/c i thopught it may had been overheating in traffic. Ruined the back tire b/c i ran over a drill bit and through the sidewall. talk about pissed. no problems since and 1800 mi on bike. pops on decel, decel fuel cut enabled. cut it back alot by leaning it out. 08 dyna stock. tmax,stage1AF,slip ons w/drilled baffles. not to change the thread but i could use input too.....
 
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Old Aug 14, 2008 | 02:09 AM
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Try backing off the enleanment. The popping is due to unburnt fuel in the exhaust due to running rich, but it also takes oxygen. So you can get a pop from going lean to rich or rich to lean. It takes unburnt fuel, oxygen and heat to get combustion. Normally your exhaust has cooled too much for the oxygen to come from fresh air.
 
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Old Aug 14, 2008 | 10:38 AM
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Originally Posted by johnnyshrooms
pops on decel, decel fuel cut enabled. cut it back alot by leaning it out. 08 dyna stock. tmax,stage1AF,slip ons w/drilled baffles. not to change the thread but i could use input too.....
In the RPMs where you get the popping, richen the AFR in the 0-14 degree TPS. Try 13.0 AFR.

Originally Posted by LilBudyWizer
Try backing off the enleanment.
The tmax doesn't have decel enleanment. Its programming is pretty basic.
 
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Old Aug 14, 2008 | 08:48 PM
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Originally Posted by ToBeFrank
In the RPMs where you get the popping, richen the AFR in the 0-14 degree TPS. Try 13.0 AFR.



The tmax doesn't have decel enleanment. Its programming is pretty basic.
That's the whole idea Frank. EFI made simple. Take that away and many of us would not have learned how fuel injection works. Even without all the bells and whistles properly tuned it does a mighty fine job.
Ron
 
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Old Aug 14, 2010 | 05:58 PM
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I have 08 Ultra with Tmax around 300 miles has been great untill now. Riding today very hot weather 150 mile trip half way through it my bike started missing and poping like like it was out of gas. The engine light came on after a while and it started running fine as ling as the light was on. When I got home hooked the computer up the unit was very hot and had codes but I dont know where to find what these codes mean.
 
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Old Jul 31, 2011 | 06:19 PM
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over the weekend i went for a ride. Coming into my camp site my bike turned its self off. It acted like it ran out of gas. I hit the start switch and nothing...... I reset the ignition switch and hit the run switch and the fuel pump does not turn on and prime along with the starter does not engage... My blinkers also for some reason are not working. My bike will show what gear it is in but thats about it for lights .I have traced out all my wires and it seems i have control power... Is this maybe a problem with the Thunder Max?
 
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Old Nov 26, 2013 | 01:13 PM
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Default T Max Pop

another thing that you have to look at it exhaust leaks that will cause them to pop use some copper RTV on the muffler joints
 
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