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TFI and pipe soot build up

jetwrench

Member
Hello.
Purchased a TFI for my 08 sporty 1200 low 800 miles ago and the last 100 miles noticed my forward slip on muffler tip has much more soot build up than the rear. The bike has rush balony cut slip-ons and stock intake and the TFI is set at stock recommended settings. The bike runs fine, just curious if others have seen this before, one thought was airflow difference from forward to rear pipes. Your thoughts are greatly appreciated.
 
Thanks, Since one pipe has much more buidup than the other is it possible to have a richer mixture on the forward cylinder than the rear with the o2 sensors disconnected?
 
jetwrench,

The key part to your initial posting is that "the bike runs fine". For only noticing this over the last 100 miles we would recommend not to change anything. The key component which probably changed is your fuel quality which caused the soot to build up. It is true that a rich condition can also have this affect, but before jumping to making changes based on this info we would first suggest to check and answer how your fuel mileage is doing? If it has dropped considerably then we would suggest turning the Green and Yellow pots down a little.

A lot of V-Twin or multiple cylinder engines have built-in offsets between each cylinder. Being a piggy-back controller we are passing this information on. The O2 sensors help monitor this offset when they want the bike to run as lean as possible around a 14.7 AFR. This is not best power. When we disconnect the O2 sensors and add some fuel, we are getting into the 13's for AFR and the cylinder offset is not critical.
 
Thanks for the reply,
Yes i'm not concerned about the build up difference, just curious what causes it (i'm quite the nerd that way). Being stock other than the slip-ons, after installing the TFI I noticed the bike just ran much smoother and cooler. Now I can't wait to get the dollars for a new intake and see the power gains! Thanks Dobeck, very pleased with your product!
 
I just gotta say that I really respect a company that cares enough about their customers to monitor a forum and give feedback. Thanks Dobeck.:)
 
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At the rate the EPA is going, I fully expect Dobeck to come out with a TFI for my rider lawnmower and my Weed Whacker. Of course, they will both be used in off road situations, so that will make them legal.
 
At the rate the EPA is going, I fully expect Dobeck to come out with a TFI for my rider lawnmower and my Weed Whacker. Of course, they will both be used in off road situations, so that will make them legal.

Thats funny, The EPA wants to ban them because of noise and too much pollution already, Whats next?:p
 
Got a sears leaf blower for the school it runs so lean i cant take it off last choke poss, no air screws to adj on carb..TX.. EPA
 
Got a sears leaf blower for the school it runs so lean i cant take it off last choke poss, no air screws to adj on carb..TX.. EPA

Take it back LOL, these carbs are not much to begin with and not serviceable, try some sea foam:p
 
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