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Thundermax , NEED Help !

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Old Jul 17, 2010 | 06:14 PM
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jaysonL
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Default Thundermax , NEED Help !
Again ! Bike backfired real loud on me as I was just cruising at 45mph . Light throttle . No Check engine lights , no codes . I pulled over , re initialized the map . Tried to start...nothing . Re initialized again . Started this time . Bike ran rough , but got me home . I linked to the bike with lap top , and found no diagnostic codes . Only thing I can see in the fuel flow for the rear cylinder is all over the place . Looks like a roller coaster . Front flow looks great . I'm really sick of this thing . I had to replace the front o2 sensor all ready , now this . Also , I replaced the battery last week on the bike . But it ran fine all week .
 
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Old Jul 17, 2010 | 08:56 PM
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eleft
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The rear always looks odd compared to the front. Have you done read and write fuel offsets.
Also is the base map correct for your engine and any modifications added.
Al
 
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Old Jul 17, 2010 | 09:53 PM
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I have the proper map , and several auto tune read/write sessions . Bike was running good . Then , all of a sudden....
 
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Old Jul 18, 2010 | 07:30 AM
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AFHuey
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Have you checked your rear pipe to make sure that it's not leaking or loose? As soon as you start getting clean air in there, it'll start messing with the o2 sensors and T-max will start trying to figure it out and tune it....but it's like chasing it's tail.
 
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Old Jul 18, 2010 | 10:47 AM
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I figured it out . I replaced the rear o2 sensor . Don't buy them from Zippers , or J&P cycles . I got one from Advanced auto for way cheaper .

http://shop.advanceautoparts.com/web...730616-P_291_R
 
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