EVO All Evo Model Discussion

reversion ?

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Old Mar 26, 2012 | 05:29 PM
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Default reversion ?

I was wondering, what are the symptoms of exhaust reversion?
I've got a 90 softail that I put new drag pipes on and
I'm just wondering.
 
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Old Mar 26, 2012 | 07:11 PM
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Gas dripping out of your air filter.....
 
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Old Mar 26, 2012 | 08:46 PM
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I don't have that, but when I put my new pipes on
I'm getting a bit of hesitation in 1st gear at light throttle.
Plugs look a tad lean but show some color, it's not carb coughing
I'm jbike runs great, except at light throttle. Reversion?
 
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Old Mar 26, 2012 | 09:01 PM
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Originally Posted by the blob
I don't have that, but when I put my new pipes on
I'm getting a bit of hesitation in 1st gear at light throttle.
Plugs look a tad lean but show some color, it's not carb coughing
I'm jbike runs great, except at light throttle. Reversion?
If the flow is increased it can have the effect of leaning it out some, what kind of exhaust did you have on prior to the drag pipes?
 
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Old Mar 26, 2012 | 09:21 PM
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Stock header with slipons. Think I should up the slow
To a 48 from a 45?
 
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Old Mar 26, 2012 | 10:50 PM
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Drag pipes are notorious for giving you a hesitation....try the bigger slow jet and maybe a spacer under the slide needle....lollipop baffles are a good fix too......google them or search this site for the how and why.
 
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Old Mar 26, 2012 | 11:32 PM
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Thanks for the help all! Ill try the bigger jet as I'm already maxed
Out on the mixture screw(3.5 turns out). If not ill just
live with it as the bike does run pretty good.
 

Last edited by the blob; Mar 26, 2012 at 11:35 PM. Reason: spelling.
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Old Mar 27, 2012 | 12:15 AM
  #8  
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just watch you don't add too much fuel to not enough air.



as mentioned reversion will show up as fuel dripping from the air cleaner element.
at certain specific rpms, the pulse wave in the exhaust reverses up the header, past the still open exhaust valve, out the opening intake valve. this occurs more often say 3500 ish rpm.


I only tried a drag pipe system once--- on that bike I lost so much bottom end I was slipping the clutch to get going from a stop-- after 2 days I went back to where I'd been.





mike
 
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Old Mar 27, 2012 | 06:40 AM
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What kind of aircleaner are you running?

Drags increase the exhaust flow but you need a hiflow aircleaner to make everything work together.

Are you getting deceleration popping and if so, how much? If it's not popping bad then it's probably not all that lean. I'm not a big fan of dumping more fuel in these engines, if you up the slow jet, try a 46 with one washer under the needle and while you are at it, take the carb off and clean it out real good if it has not been done lately.

Doug
 
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Old Mar 27, 2012 | 09:24 AM
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Doug, the air cleAner is stock and I get no decel popping at all.
No carb coughs either. Plugs are a tad chalky on the ground strap
But porcelain shows a light tan. I think what ill do is turn my thumb
Screws more and see.
 
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