2021 Aprilia RX 125 and SX 125 First Look Preview

We dive into the specs of Aprilia’s redesigned lightweights.

Aprilia redesigned its lightweight 125cc streetbikes for 2021.Aprilia

Aprilia is carrying on its proud tradition of building high-end small-displacement mounts this year, with a redesign of its SX 125 and RX 125, its foreign-market 125cc, four-stroke SuperMotard and dirt bike.

The Aprilia SX 125 is available in Rally Tribute livery for 2021.Aprilia

The tiny thumper that powers the little beasts gets a rethought top end this year, thanks in part to new Euro 5 emissions regulations. Aprilia says it raised the intake to feed air more directly to the all-new head, which sports revised cams and a new combustion chamber. The exhaust is also entirely new, featuring a new catalytic converter and muffler. The result is a wider torque curve and peak power lower down the rev range. No more wringing your 125′s neck to get it moving.

With 17-inch wheels front and rear and front ABS, the 2021 Aprilia SX 125 should punch above its weight in the corners.Aprilia

The Bosch ABS brakes get new gadetry too, to keep the front wheel from locking up and the rear wheel from lifting under heavy braking. The SX gets a 300mm disc up front backed with a 220mm unit out back, while the RX gets a 260mm front rotor backed with the same 220mm rear disc.

Both the SX 125 and the RX 125 got an all-new head this year to improve flow and meet new emissions requirements.Aprilia
The little bikes also got all-new exhaust systems, with a rethought muffler and new catalytic converter.Aprilia

The little bikes both get 41mm inverted forks with 240mm (9.4 inches) of travel, and a single shock out back with 210mm (8.3 inches) of rear wheel travel. The SX wears 17-inch spoked wheels with black rims, while the RX gets a 21-inch front wheel and 18-inch rear wheel.


Both the RX and SX weigh in north of 290 pounds fully fueled, and have seat heights above 34 inches. They may be small capacity, but smaller riders might still need to lower the ride height.Aprilia

Unfortunately, it doesn’t look like Noale has plans to bring the little Aprilias to these shores.

With a 21-inch front wheel and 18-inch rear, the RX 125 is a proper, full-size dirt ripper, despite its diminutive powerplant.Aprilia
The RX is available in the same three colorways as the SX.Aprilia
According to the spec sheet, both the SX and the RX get close to 10 inches of front suspension travel.Aprilia
For those on Europe’s tiered licenses, the little Aprilias are a brilliant, premium solution. Unfortunately, they aren’t going to be sold in the US.Aprilia

2021 Aprilia SX 125 and RX 125 Technical Specifications and Price

Price: TBD
Engine: 124cc, DOHC, liquid-cooled, 4-stroke single-cylinder; 4-valve
Bore x Stroke: 58.0 x 47.0mm
Compression Ratio: 12.0–12.6:1
Fuel Delivery: Magneti Marelli EFI w/ 32mm throttle body
Clutch: Wet, multiplate
Transmission/Final Drive: 6-speed/chain
Frame: Twin-tube steel
Front Suspension: 41mm inverted fork; 9.4 in. travel
Rear Suspension: Monoshock, progressive link; 8.3 in. travel
Front Brakes: Floating caliper, 300mm stainless steel disc (SX) / floating caliper, 260mm disc (RX)
Rear Brake: Floating caliper, 220mm disc
Wheels, Front/Rear: 17 x 2.5 in. / 17 x 3.5 in. (SX) / 21 x 1.85 in. / 18 x 2.15 in. (RX)
Tires, Front/Rear: 100/80-17 / 130/70-17 (SX) / 90/90-21 / 120/80-18 (RX)
Wheelbase: 56.1 in. (SX) / 56.3 in. (RX)
Seat Height: 34.6 in. (SX) / 35.7 in. (RX)
Fuel Capacity: 1.8 gal.
Claimed Wet Weight: 295 lb.
Warranty: TBD
Available: TBD
Contact: aprilia.com