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New slip on backfire more.


Old 08-01-2017, 11:38 PM
Brent09 is offline
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Default New slip on backfire more.

09 Ultra classic. I bought this bike a few years ago and wasn't happy with the stock slip on sound. I bought some slip on on- the sound much better! My question is, now it pops n farts when I'm slowing down, never did that before??
Didn't use any sealer etc...juse tightened up the Clamp? Did I forget to do something?
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Old 08-02-2017, 12:59 AM
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As your exhaust gasses exit faster and they have still a very high temp, this makes them react with the surrounding O2 in the air.
You need to increase your decel setting to inject a bit more fuel. This will prevent the exhaust gasses from "popping"
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Old 08-02-2017, 04:54 AM
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It's common folk-lore that we can change certain things like mufflers, without retuning the bike to compensate. That is not always the case, as you may have found. By all means check that you don't have any leaks, either in the induction side or exhaust, otherwise look to retune your bike. You may be pleasantly surprised how much better it can ride!
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Old 08-02-2017, 10:35 AM
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Get a tuner and tune the bike...
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Old 02-13-2018, 08:38 AM
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My bike did the same thing now that the exhaust is open and free flowing.The FP3 tuner got rid of my decel popping and gave it a bump in Power.
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Old 02-13-2018, 09:13 AM
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it doesnt hurt anything, I like the popping and burping because it scares sockermoms in minivans and little kids.
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Old 02-13-2018, 09:22 AM
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yep, the lean out or unburned fuel collects in the exh till there is enough to ignite. so that tells me hd does not cut fuel off on decel till under a certain rpm, which if it did, the problem would not be there.
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