should i expect h.p./torque loss or gain?
 

I'm changing the S.E. slip-on exhaust and S.E. backplate that i have on now,for a set of vance and hines shortshots and a S.E. heavy breather . also I have the sert. do you think i will lose h.p. and torque with this change over,or gain a little? oh yeah,i have an 09 fatbob and have no problem with breaking the tires loose in the first few gears pretty easily, hopefully will be able to continue to do so.thanks for you're input and opinions.
kappy

I'm not the one to answer this because I had my pipes/ac put on before I took delivery of the bike but I'd be inclined to say yes. Even being a 2-2, they're bound to be better performing than the stock headers.
My setup won't win any land speed records but it'll haul plenty o' balls.

Got near enough that set up and it's fast enough.. and plenty of grunt in 5th and 6th..mine only pulls chicks though lol....

Personally if you have no problems breaking the tire loose then the tire is over inflated, too hard, or you are soon to need a clutch. Doing what you have mentioned you should gain both HP and Torque. The short shots are not gonna hold the back pressure as the slips did, but you are still gonna gain torque just through getting everything freed up and not running lean any more. More air flow, more fuel flow, free flowing exhaust make it easier to gain power

Thinkin' out of the box....
 

The bike would probably go just as fast if you lost 20 lbs. So, if you can afford to lose 20 lbs. your bike will be faster and so will you and you get to save mod money plus your food bill will be lower. Win, win, win, win situation!!! :icon_goofygrin:

I would suggest a K&N filter tho...........

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... or flat... no way a stock bike is going to do that without totally dumping the clutch... lmao

To answer the question like the above posters mentioned freeing up the breathing will offset any losses on the low end.

As long as you also retune, you may or may not notice torque, but the WOT power will net about 5 ponies. Not a lot but you should notice it. Low seed burnouts is more about torque, I think. The louder pipes will make it sound a lot faster, however.... :)

First thing you need to do is change the pipes,then go for a 20 min. ride.Your computer will correct its self.Now change the air filter.Again the same thing will happen. This is only true on the later model FI bikes.Mine is a 2008 and it worked fine on mine.The system will return you fuel ratio bake to the stock setting without you giving your dealer any more money He might tell you different,but my dealer told me that Amsoil would ruin my engine.Go figure.Enjoy your ride and keep burning up those tires.