The Polaris® Slingshot® and the Can-Am® Ryker and Spyder have small horns and no spare room for an air tank. You can swap the factory horn for a plug-and-play kit, or carry a portable battery train horn. This guide compares the two and explains why most riders end up with both.
Why the Factory Horn Falls Short on a Three-Wheeler
Under federal rules, the Slingshot, Ryker and Spyder count as motorcycles. The federal definition in 49 CFR 571.3 covers any motor vehicle "designed to travel on not more than three wheels in contact with the ground." Most states now call the Slingshot an autocycle for licensing. Polaris announced in 2018 that Florida was the 43rd state to make the switch, so a regular driver's license is enough to drive one. But the horn is still sized like a motorcycle horn, while the Slingshot drives in car traffic.
You sit low and in the open, next to pickups and SUVs with their windows up. One Ryker Rally owner described the stock horn as a "beep beep." When a crossover starts drifting into your lane, that isn't enough. The aftermarket has noticed, and Slingshot and Ryker owners now have their own horn upgrade category.
The Plug-and-Play Horn Kits You Can Buy
Most of these kits come from specialty powersports shops, and SlingMods carries the most popular ones. Here's what the main options list on their product pages:
| Kit | Fits | Rated output | Listed price | Power source |
|---|---|---|---|---|
| SE Performance Plug N' Play Dual Horn Kit (SM-9311) | Slingshot 2020–2024 | 110 dB | $99.95 | Vehicle 12V via factory horn harness |
| SE Performance Dual Horn Kit (SM-4989) | Ryker 2019–2026 | 110 dB | $99.95 | Vehicle 12V, built-in relay |
| Electrical Connection / Flosser Air Horn Kit (SM-280) | Slingshot 2015–2024 | Not listed | $119.95 | Vehicle 12V, triggered by the factory horn button |
| Lamonster MOTOHORN 3.0 with F3 Plug-N-Play | Spyder F3, 2015 to current | Not listed | $129–$159 | Vehicle 12V, small onboard compressor |
These are good products for what they are. The SE Performance kits plug into the factory harness and mount where the stock horn was. On SlingMods, the Ryker kit averages 4.9 out of 5 across 96 reviews, and the Slingshot kit averages 4.64 out of 5 across 39 verified buyers. Owners say the horns are much louder than stock. One Ryker owner wrote that it was "almost a train."
The key word is "almost." These kits are rated at 110 dB, and the two air horn options don't publish a dB figure at all. None of them is a true train horn, because a train horn needs a real volume of compressed air. That usually means a tank, and a Slingshot or Ryker has nowhere to put one.
Where Plug-and-Play Kits Get Tricky
"Plug and play" sounds simple, but owner reviews tell a more mixed story:
- Tight fit: SlingMods lists the Ryker kit as only "Mostly" plug and play. One reviewer had to re-route a horn's wiring to keep it off a bar between the front wheels.
- Hard-to-reach mounts: On the Slingshot kit, one buyer said the driver's-side horn was hard to reach with a cold-air intake box in the way. They also noted that the replacement bolts use a 10 mm head instead of the original 5 mm Allen.
- Hood clearance: One Flosser buyer found the horn touched the hood when it was closed, and had to move it back to the factory bracket location.
- Different install times: One Slingshot owner finished in about 15 minutes, while another spent about an hour on the driver's side.
None of these are deal-breakers. They do mean you're working under the front fascia with a socket set, dielectric grease and some patience. You also end up with a horn that's somewhat louder than stock but nowhere near train-horn territory.
The Portable Battery Train Horn Option
A portable battery train horn skips the vehicle wiring altogether. It's a self-contained unit with its own compressor and trumpets. It runs on a cordless tool battery you probably already own, such as a Milwaukee® M18™, DeWalt® 20V MAX™ or Ryobi® ONE+™ pack. You don't need a tank, a relay or any wiring, and you don't have to pull the front fascia off. You set it in the passenger footwell or strap it into the storage area, and fire it by hand or with the wireless remote.
The difference in sound is large. Our dual-trumpet horns are rated at 130 dB, quads at 140 dB, and the Extreme and Boss Series at 150 dB. According to the Federal Highway Administration, each 10 dB increase sounds about twice as loud to the human ear. So a 130 dB dual sounds roughly four times as loud as a 110 dB plug-and-play kit, and a 150 dB unit is two more doublings beyond that.
For a Slingshot owner who wants the loudest option, the Extreme Series Train Horn for Milwaukee® 18v Battery is our flagship. It's a 150 dB quad that comes fully assembled and runs on any M18 pack. The standard remote reaches 160 ft, and you can upgrade to a 2,000 ft long-range remote. That range is handy when the horn is in the Slingshot's storage area and you're blasting it at a car meet from across the lot. It's also the same horn you'd carry in a pickup. Our best train horns for trucks roundup covers how the tiers compare there.
Plug-and-Play Kit vs Portable Battery Horn: Side by Side
| Plug-and-play kit | Portable battery train horn | |
|---|---|---|
| Rated loudness | 110 dB or unlisted | 130 / 140 / 150 dB by tier |
| Install | Under the front fascia, factory harness, 15–60 min per owner reports | None, just slide in a tool battery |
| Power | Vehicle 12V system | Its own tool battery, separate from the vehicle |
| Triggered by | Factory horn button | Trigger on the horn or wireless remote |
| Moves to another vehicle | No, model-year specific | Yes: truck, boat, UTV, campsite |
| Replaces the factory horn | Yes, or runs alongside it | No, it works in addition to it |
The last row matters most. A plug-and-play kit stays your everyday road horn. A battery train horn doesn't replace it, and we'd tell you to keep a working factory-style horn either way. We explain why in our guide to keeping your factory horn. The most practical setup for these vehicles is a modest plug-and-play kit on the horn button for traffic, plus a portable train horn for when you really need volume.
Mounting and Carrying It on an Open Three-Wheeler
A Slingshot or Ryker is open to wind, rain and road vibration, so plan where the horn will ride:
- Strap it down. Don't leave a horn loose on the passenger seat. Use a cam strap or a bracket. Our mounting guide covers clamp and bracket options.
- Secure the battery. Vibration can work a tool battery loose over time. Here's how to keep the pack locked in and theft-resistant.
- Stow it when parked. An open cockpit makes a portable horn easy to steal. Take it with you or lock it in the storage area.
- Want it on the horn button? It can be done, but read our guide to wiring a battery horn to the factory button first so you understand the trade-offs.
If you also ride a two-wheeler, the same approach works there. Our best train horn for motorcycles guide covers Harleys and sport bikes, and the ATV and side-by-side guide covers trail rigs where the same horn can go along.
FAQ
Is it legal to run a train horn on a Slingshot or Ryker?
Horn rules are set by each state, and many state codes ban horns that make an "unreasonably loud or harsh" sound on the road. Use a train horn off-road, on private property, at events, or as an emergency signal, not to blast traffic. Keep a working road horn as well. Our train horn legality overview breaks down the rules.
Can I fit an air tank train horn kit on a Slingshot?
In practice, no. The plug-and-play kits sold for these vehicles are compact electric or compressor-only horns because there's no good place for a tank. A battery horn carries its own compressor and power, so it doesn't need one.
Will a battery train horn drain my Slingshot's battery?
No. It runs only on the cordless tool pack plugged into it and never connects to the vehicle's 12V system.
Which tier makes sense for a three-wheeler?
A 130 dB dual is light and already roughly four times as loud as a 110 dB kit. If you go to car meets or ride long open stretches, a 140 dB quad or a 150 dB Extreme gives you much more reach. Before you blast one at close range, read our hearing safety guide.