I've asked the same thing. The chart above was one of two that a local dealer did Stage 1's on, both had almost identical numbers. They had shown a Dyno sheet on a Stage 1 flash (no Dyno tune) that had about 1/2 the power and torque gain

 

It seems that the mufflers and the air box both work better than they did on the earlier models.

 

Agree that the dyno chart doesn't make sense compared to Fuel Moto charts I've seen.
Agree the M8 has better stock breather and pipes the any other OEM HD Ive owned
Agree I think i'll leave it stock too.

The HD OEM pipes sound decent just not loud but nice tone for what they have (have noticed they do get a little more volume with time)
if any upgrade it will be Street Cannon's (no tune or breather upgrade required) just for a tiny bit more exhaust note without being gnarly or obnoxious.
i like listening to tunes. I also don't want it to run harder and take away how smooth it runs.

Every HD I've owned ran smoothest when it was stock. Add performance upgrades and it improves power, acceleration, etc with a sacrifice of comfort due to it running rougher too.

For those that want the best bang for the buck I think stage 2 with a cam that has a broad band TQ increase is the way to go. displacement increase and much more cost do not interest me at all. Of course I would bet that even the stage 2 will slightly degrade the smoothness of the M8.

 

The Evo's were so choked down from the factory and made small numbers that it took very little effort and money to nearly double the horsepower and torque.

The twin cams were so lean from the factory to meet EPA regulations that simply adding more fuel and slightly more aggressive ignition timing produced some good gains but not as much of a difference as with the Evo because they were already more efficient, mostly because of better heads.

The M8 achieved EPA compliance through efficiency and as a result, less power was left on the table. Sure, more is to be had but since you are already at a very good starting point, there is less that was left on the table with existing components. An argument could be made that since the various M8 screaming eagle kits are EPA compliant, the bikes could have left the factory with those components installed and instead were held back for the purpose of an added revenue stream, especially since many riders are happy enough with the bike as it is now. The $1,595 kit that takes a 107" standard M8 to 114" to me is probably the sweet spot right now with regard to bang for the buck. Despite matching the displacement of the CVO's, it actually produces slightly more torque than the CVO, probably due to higher compression.

http://mstore.harley-davidson.com/st...107ci-to-114ci

Another thing is everything from food to the new bikes costs a lot more today than it did thirty years ago. In the late 80's $15,000 bought you a loaded to the max touring bike. Sportster were only $4,999 brand new. Those same models are just about double the price now.

Funny enough, Jeeps in the late 80's were $12,000 to $15,000. Today most Wranglers are in the upper thirties to lower forties new, and the used ones that sold for $12,000 when new are commonly going for twenty thousand on up.

Remember the ninety nine cent whopper at Burger King? Now a trip through the drive through can easily set you back $8 per person by the time you pay for the so called value meal.

 

"if any upgrade it will be Street Cannon's (no tune or breather upgrade required)" actually for the first time ever HD states ECM recalibration required with Street Tuner for just Street Canons, which I did but left the stock intake alone..runs just as smooth as it did stock with an increase in redline rpm's..so for under $1000 got a nice looking, sounding and performing upgrade and don't have the need or desire to go any further

 

A lot of great points made in this thread. Sorta reinforces my absolute lack of conviction and constant flip-flopping on doing any performance upgrades to the Road King.

 

I don't think it's as simple as "one" 3rd party component being your key item. If your going to be buying new components and want the best bang for your buck, I'd call Fuel Moto and get a head pipe, slip-ons, air cleaner and a tuner.

You will hear all kinds of rambling on here, but flat out you won't get a better full package deal, especially one that offers the kind of support they do.

 

My suggestion is run stock for now except for replacing that ugly *** air cleaner. In a few years when you start getting bored with the bike, do a refresh to include performance improvements using what then be more mature aftermarket components. The bang for the buck will be better by then and you won't be in a continuous state of rebuild like some are now.

At least one guy on this forum is on his third performance build of his 2017 M8. Yeah, one bike, torn down three times with completely different components that don't build on each other, and he is not a manufacturer or performance shop or anything. Just a guy with money to burn that takes his bike apart and puts it back together instead of riding.

 

I don't think I've ever seen any HD literature stating that X performance exhaust does not require ECM calibration. HD has always stated that any changes in either intake or exhaust required ECM calibration. If it wasn't specifically stated, it has always been implied (remember those famous "Downloads"). Any who, for exhaust, even on an M8, it's been proven many, many times that the bike will actually run fine without a tuner, but they will run better and be in full HD/EPA compliance if you add THEIR tuner. Which is fine. 17 changed things a little so, well you know...

If you already have 1000 bucks into a tuner and pipes it's different that you wouldn't put an intake on it. They are only a few bucks more and you get a wee bit of upper performance and better filter media; however, I get it. Your bike, your deal. Not judging. But hell I would.

 

I cleared out some parts, gave away two sets of stock post 2013 headers. 2 full Stock 103 AC's. A set of 12 inch and set of 13 inch air shocks. Brand new stock tail light. The stuff just piles up and never gets used .
Traded for the M8 and have left it alone except for some LED,s. The 2016 hi out put 103 was a turning point for me. I did the header to get rid of the CAT with a Fuel moto 2-1-2 ceramic coated worked great. Changed nothing else . I did add some LED's and my BAL tail light.
I know reading the net you would not thinks so but they run pretty darn good now.