Hi WO,
Just thought I would add my 02. So far everyone's suggestions seem pretty good. It comes down to personal preference. I disagree that warranty will be voided with any mild changes, even sert. 99% of dealers will cover, especially your own. There are a few dealers that really suck, and only want to sell accessories, no engine anything. Stay away from them and you will have a great time. Larger dealers are really into the modifications, and certainly any one of those will tow the line if they approve an install.
But as far as performance, the reality is that there is not going to be ANY seat-of-the-pants discernable difference when you go to your choice of aftermarket Air Filter (say more intake air), slip on's (more exhaust air flow) or true duals (more air flow but less torque than stock crossover arrangement and slip on's) versus stock, and finally, 2 gozinta 1's (more torque than TD's and Stock, but naked on one side) But when you make the change over from stock, whatever your choice, make sure you have a way to change, and monitor, the air fuel across the board. Of course more fuel will run the motor cooler, but to much and it is inefficient. To lean, well, you are defeating the purpose then.
Stay away (IMHO [smiley=nervous.gif])...from gadgets that lie to your ecm. Here's why. If for some reason you had a failure of the add on lying machine, you will be running so lean that you can burn stuff up. So you now have a bike you should not ride, and should get to a dealer. If you had a SERT installed by Harley, why enjoy the warranty. The first map costs, and any good dyno shop came make it right because you travel with the inteface module. And that's only if you have a problem. But if you got one of those funky market hype Fuel Pacages for example, and it fails, what are ya gonna do? Roll into your harley dealer and buy another one or wait for an exchange or repair? Or just have em plug the SERT Module in and get you going fast. Any way I see it is this: If Harley's ECM codes are secret, and they want to sell you a sert for the privledge of using a map that can be changed, to specifically change fuel to handle open air systems, so be it. But to try and run aftermarket and not change to a SERT? Well, THAT would be a warranty breaker for sure.
JMnotsoHO
Rhino
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