Brand new Harley Fat Boy. Which type of aftermarket pipes?

I am running late this morning, but I will try to answer your question more tonight.

But a quick note, no, you CAN'T run straight pipes with no tuning of the ecm. If you are going this far, you NEED to have a h-flo air cleaner installed, let the engine breathe...pipes & no air cleaner...imagine try to run a marathon inhaling through one nostril and exhaling through your mouth...not very effieicent is it????

EDIT...continued.....

I guess James doesn't realize how severely restrictive HD's mufflers and air cleaners are....a SIMPLE change to a SE air cleaner and SLIP-ON mufflers and proper tuning will yield about 12 hp and 10 ft/lbs of torque...AND...drop the engine temps as much as 15-20 degrees!!!...and they are not THAT loud, but sound GOOD.

Now back to your question....

Technically, ANY change to exhaust or intake requires injection remapping, but in the real world, HD's SLIP-ON mufflers only can be installed with no remapping, it won't run the best, but "ok" it will still be very lean and hot running. Aftermarket pipes are ALOT less restrictive than HD's mufflers and will REQUIRE remapping. ANY change to the air cleaner REQUIRES remapping!!! HD, like everyone else, runs their bikes lean for EPA standards, lean conditions create excess heat which is bad, richen the mixture up, it runs better with more power and runs cooler.

Read up on two of my answers regarding PROPER engine tuning......

http://answers.yahoo.com/question/index;_ylt=AgmoV...

http://answers.yahoo.com/question/index;_ylt=Am9Gb...

A Harley-Davidson Fat Boy is a slow bike. Changing pipes will have little effect on that. It will make it loud, however.

There is no earthly reason for anyone to put up with loud, slow bikes. Loud bikes are bringing on enactment of restrictive laws curtailing the use of ALL motorcycles. If we don't regulate ourselves, the lawmakers will regulate us out of existence.

I would rather ride quietly than not at all.

Edit: Note to Harley Guy: I am very much aware of how strangled H-Ds are by their intake and exhaust systems. But the upgraded power you mention "doesn't amount to a hill of beans" when applied to a 313 Kg (688 lbs.) motorcycle. Make that more than 900 lbs with the rider on board. And the vast majority of H-D owners change pipes for reasons of appearance and sound, not performance. If they wanted performance (in Harley terms) they would build up a Sportster or buy a V-Rod. Too many Harley's with "performance" pipes perform poorer than stock, and set off car alarms (which I've often seen riders do on purpose, much to their adolescent amusement). I'm just going by what I see, riding at least 6 days or evenings (and spotting HUNDREDS of other bikes) every summer week.

Fat Boy Exhaust

They talk about fatboys being slow maybe that's the new ones but a 2000 one

is about fastest Harley they make, I have rode them all in test rides in Sturgis

and Daytona and none are faster, some run about the same.

Vance & Hines make great pipes. Also, why not just take your bike to a M/C exhaust specialist & have the standard ones modified. You'll save a bucket, plus they still have the noise compliance stamped on them.

Having seen this I just have to share something because I spent endless years going from diet to diet without seeing any results until I discovered Dianas proven plan (just google it). Without a doubt the best results that I have ever achieved and I am still trim to this day.

You bought the worst performing bike you could possibly buy and now you are worried about horsepower. I think that horse has already left the barn. If you want a bike with performance you need to buy a bike with performance, not a paperweight with wheels.

Dunno about all the other bits etc but Vance & Hines pipes sound great and just ooze quality.

The Harley fixer will know about SE pipes. Maybe he will answer your question