Best Upgrades for a 2021 Street Glide
Ask five people what to put on a 2021 Street Glide first and you'll get five different answers, mostly guesses. Here's ours, and it isn't a guess. Every part below is verified to fit this exact bike.
The Touring family is built for the miles that actually add up: full fairings, real storage, and a chassis tuned for hours in the saddle, not just the ride to the coffee shop. Street Glide's handlebar-mounted batwing fairing gives it its signature silhouette; Road Glide's frame-mounted sharknose does the same job with a steadier feel at highway speed. Together they're Harley's best-selling family by a wide margin. Most Harley riders on the highway are riding one of these two.
A full build, every part verified to fit
Generated by the same verified-fitment engine that powers the builder, priced from real listings.
Built for a $5,000 budget: 10 parts, $4,904 total.
Arlen Ness Clear Tear Air Cleaner Black
$449.95Air Intake
One of the most common first upgrades on any M8. A freer-breathing intake pairs naturally with an exhaust and a tuner, and with a cam change later.
S&S Cycle S&S Cycle Black Mk45 Muffler with Black Cutlass End Cap for M8 Touring
$819.95Exhaust
The most-heard upgrade on any build: tone, weight savings, and the foundation most performance work builds on.
Daytona Twin Tec M8FI G9 Race ECU - HD M8 Touring (2021-2023.5, 2024 Ultra)
$1,071.75Fuel Tuner
Any breathing or cam change needs fueling to match. A tuner is how the engine actually uses the parts around it.
⚠ Closed-course/race product: confirming legal use for your riding is on you.
S&S Cycle Heavy Duty Compensator Ramp for M8 Models
$349.95Clutch
Clutch upgrades change lever pull and engagement feel, a common pairing with a performance build that's added more power than the stock clutch was sized for.
Kraus Moto Max Lean Heel Shifter
$265.00Foot Controls
Foot position is posture. Controls that fit your inseam change comfort on every ride.
Trask Performance Trask FL Titanium Front Axle Kit
$389.95Front Suspension
Fork upgrades: the front half of ride quality, and the half that matters most under hard braking.
Burly Brand 13" Bagger Bars
$323.95Handlebars
Bar shape sets your entire riding posture, the biggest single change to how a bike fits you.
Burly Brand Slammer Plus Shocks
$404.95Rear Shocks
Stock rear shocks on most H-D models aren't adjustable for load or rebound. An adjustable shock is usually the highest-impact ride-quality upgrade on the bike.
Original Garage Moto OG 6.5" Pull Back Risers
$399.95Risers
Bar height and reach is a comfort and control issue, not just a style one. Risers change your riding position without needing new bars.
Mustang Seats Double Diamond Extended Arm Wrap-Around Backrest for Harley-Davidson FL Touring 2014-2025
$429.00Seats
Seat shape decides how far the bike can actually ride in a day. The touring upgrade riders feel most.
⚙ Fits King Tour-Pak only -- will not fit Chopped, Grand, Razor, or leather Tour-Paks.
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Frequently asked questions
What's the most popular first upgrade for a 2021 Street Glide?
Exhaust, almost always. Usually paired with an air intake and a tuner so the sound and the breathing change together. See the build above for what that combination actually costs and fits on your 2021 Street Glide.
Will a part fit my 2021 Street Glide without anything else changing?
If it's shown in your build above, yes. Every part on this page is checked against your 2021 Street Glide's exact fitment data before it's ever recommended. And if something needs a companion part to work right, like a tuner with certain cams, that's called out on the item itself, not left for you to find out after it arrives.
How much does a typical first build cost for a 2021 Street Glide?
It depends on what you're after. The build above is a full build for the budget shown, with every part and the total priced from real listings. Set your own budget and style and it rebuilds around them.