When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Lots of tuners are advertised for the 10 and up touring bikes and make no mention of the catalytic converter. Cats burn unburned fuel. If you add fuel to cool the engine that means there will be more unburned hydro-carbons reaching the cat. Won't that increase the heat coming from the cat? If so, it seems like engine heat has been traded for cat heat.
The tech at my dealership...yes the dealer...actually recommended I do this to finish off my stage one (actually he recommended getting a new header pipe without the cat, not gutting the stock pipe), and he didn't even say "void the warranty" after it!
If your cat theory is correct, then how is it that you can get decel pop, which is unburned fuel reaching your now bigger, better breathing mufflers and combusting? Shouldn't that fuel burn in the cat if you are correct and never make it all the way back there?
Lots of tuners are advertised for the 10 and up touring bikes and make no mention of the catalytic converter. Cats burn unburned fuel. If you add fuel to cool the engine that means there will be more unburned hydro-carbons reaching the cat. Won't that increase the heat coming from the cat? If so, it seems like engine heat has been traded for cat heat.
Catalysts run hot when there is an excess of oxygen. Adding fuel cools them down provided the engine doesn't get to the point of misfiring.
And, the ECM has enough variable to adjust for making this slight change down the flow process - thus no popping.
Less restriction, more fuel to cool and ECM variance to allow this modification without the need to get it dyno tuned.
If you start to modify at the other end, i.e. CAMS, Air Filter, etc - you could easily need a fuel management or dyno tune to compensate for those changes.
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Slideshow: The bar-and-shield logo shows up on far more than motorcycles, some of the company's most unexpected products have nothing to do with riding.
Slideshow: From the troubled AMF years to modern misfires, these bikes earned reputations for reliability issues, questionable engineering, or disappointing performance.
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Slideshow: The Swiss custom shop has taken a Harley Softail and stretched it into something so long and low that it looks closer to a rolling sculpture than a conventional motorcycle.
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Slideshow: A standard cruiser becomes an intricate metal canvas in the hands of a Swiss custom house known for pushing Harley-Davidson platforms far beyond their factory brief.