I first did a Stage 1 on my Road Glide Special. Vance & Hines Pro Pipe exhaust. Do NOT underestimate the importance of a good exhaust. It's enormously important.

The Stage 1 made a significant improvement, very noticeable. Then I went to a Stage 2 with a great combo hp/tq cam specifically designed for broad powerband. Holy ****. 98/108 at the back tire. Again, the Pro Pipe is part of that result.

Stage 2 is generally considered the biggest "bang for the buck" that you can do.

Going bigger displacement, head work, etc., will absolutely continue to give you more power, but you will start to get to the point of diminishing returns, where you will keep spending more and more money, but you won't be maximizing your "hp/$."

 

FWIW: I am getting a new 2020SGS and going straight to Stage 2. Everything I've read and researched said that is the sweet spot. Good luck with your choice!

 

I have 107 RG M8. Did stage 1, but wasn’t satisfied, so went stage 2.
As others have posted, stage 2 makes the real difference, at least for M8.

(Stage 1 did a lot for twin cam and EVO engines, but M8 needs stage 2.)

 

had stage 1 on my 114 for 8 months. Put a cam in a couple months ago. no brainer for me. the cam actually gave the bike about 35% more power at around 3200 rmp. the stage 1 just gave the bike better crisper throttle response. now the bike is a blast to ride. front wheel practically lifts off the ground.

 

Stage II for sure. As others have said, best bang for the buck. You won’t regret it!

 

I can never remember which stage is what. Air cleaner and exhaust (stage 1?) gave me nice sound and very little performance bump. The Andrews M462 cam (stage 2?) really took things to the next level. I know stage 4 is piston jugs and head work, which is where I will be going. I guess stage 3 is somewhere in between. There was a day when we did what we could afford and called it what we had. Often, this was done incrementally according to fatness of wallet. I guess that was stages of upgrade. After 20 years of being out of the saddle, so much has changed.

 

Sounds like me, I rode a carbureted bike up until last year, when I told people all the work I did to it they would ask, what stage it was or is that a stage llll.