Slip-On Exhaust for the 2015 Harley-Davidson Road Glide Special | DOIN’ TIME

Long-Term Update: Nightstick slip-ons and Ventilator Elite air cleaner

WRIST: Andy Cherney
MSRP (2015): $23,699
MILES: 8,495
MPG: 41
MODS: Screamin' Eagle Nightstick 2-into-2 Mufflers, SE Ventilator Elite Air Cleaner
UPDATE: 5

From the start of the Harley-Davidson Road Glide's tenure at Motorcyclist, I swore that I wouldn't deign to put a new pipe on the thing. The stockers sounded and looked fine, I said, and I was more than cool with the performance of the stock air cleaner (Harley's own copy says it all: "It lets the engine breathe better... but it's also designed to give you more legroom and provide better airflow around the rider.") Plus, I just didn't think anything in the P&A catalog matched the Road Glide's aesthetics any better. Remember, we're pretty much limited to H-D stuff, unless there are no other options there.

Never say never. After all that huffing and puffing, I got talked into putting on a set of new Nightstick 2-into-2 Slip-On Mufflers ($500), along with a Screamin’ Eagle Ventilator Elite air cleaner ($300) to balance things on both ends. Because, yea, sound does matter.

I had to admit the chrome Nightsticks cut a nice silhouette when installed on the bike and came off appearing a bit more restrained than the stockers, but with industrial-looking end caps (similar to those tunable SuperTrapp disc units of yore, but without the tune-ability) to add some edge to the Glide’s profile and rear end. They’re an easy addition to the original header pipe and muffler hanger too. The chrome Ventilator Elite air cleaner brings a slightly dated older oval shape that we didn’t feel really matched the new Glide’s more modernist lines, but whatever; it’s meant to be an appropriate match to the new pipe. The Ventilator also comes with a high-flow filter element (as you'd expect), back plate, protective rain sock and all necessary mounting hardware.

Because of the mufflers and new air cleaner, Harley’s techs needed to download new software to recalibrate the ECM (normally your dealer would handle this step)to compensate for the exhaust’s changed back pressure and the higher-flowing intake. As a side note, the software also disables the EIMTS (the engine idle temperature management system) , but that can be turned back on via the Vehicle Info button, which displays Vehicle Status settings.

On the bike, the Nightstick exhaust sounds surprisingly low-key, adding just enough bass to the lows and a bit more crackle up top, without ever coming across as obnoxious. The big question, though, is does enhance performance? The short answer is, well..not much. After running the Harley on the dyno to obtain some baseline numbers, we recorded a 71.5 peak horsepower at 4,600 rpm, with a torque peak of 89.2 pound-feet at 3,500 rpm.

With the new pipe and air cleaner, horsepower nosed up a bit to 73.2 hp, with this peak coming later, at 5,100 rpm. Both the stock and modification curves ran nearly parallel, so the power builds up virtually the same. The new install had the opposite effect on torque output however, with the new 87.7 pound-feet coming a touch earlier in the rev range, 3,300 rpm, but taking more time to get there, and never quite matching the stock peak of 89.2 pound-feet. The big payoff may be an intangible, but as I rumbled up the freeway onramp, pipe in full song, I had to admit the 'Stick sounded waaay better than the stocker, with none of those tinny, neutered highs, and just enough low-end rumble to really round out the Road Glide's attitude.