Transition Regulator SX E-Mountain Bike

Regulators, mount up!

The all-mountain workhorse is here to deliver fun on every trail.

The Regulator SX is our all-mountain workhorse designed to provide a nimble and responsive ride with big power. No trail is too tame or gnarly for the dedicated mixed-wheel platform with 150/160mm travel and geometry that promotes agility and playfulness. The Regulator will be the choice for riders looking for a chassis that excels in a variety of terrain with the added assistance of a Bosch Performance SX drive unit. Known for its legendary reliability, the SX drive unit delivers 60Nm of torque for a powerful and natural ride feel. Enclosed in the downtube is a 400Wh battery to power big rides while remaining sleek and lightweight for the category. For those looking for extra range, the 250Wh Bosch PowerMore range extender will power you up to 650wh for all-day adventures. This combination provides the best range-to-weight ratio for those who value lighter ride characteristics, giving you the best of both worlds with one of the most reliable, powerful, and intuitive motor systems available on the market.

AVAILABLE COLORS:

Anthracite

Platinum

SELECT BUILD

$9,499 USD

SELECT SIZE/COLOR

Small

Ships appx: Q2 2026

Small

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Medium

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Medium

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Large

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Large

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X-Large

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X-Large

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$9,499 USD

IN STOCK: Ships within 2 business days

FREE SHIPPING: We offer free shipping on all bikes and frames, see checkout for additional details.

SHIP TO DEALER: If you prefer picking your bike up from your local authorized Transition Bikes dealer with free professional assembly, please make sure you choose Ship To Dealer during check out.

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PRICE

$9,499 USD

FRAME

Regulator SX Carbon 150mm

WHEEL SIZE

Mixed

DRIVE UNIT

Bosch Performance Line SX (BDU31)

BATTERY

Bosch CompactTube (400wh)

DISPLAY

Bosch Kiox 400C

ASSIST SWITCH

Bosch Wireless Mini Remote

REAR SHOCK

RockShox SuperDeluxe Ultimate
(205x60mm)

FORK

RockShox Lyrik Ultimate
(160mm)

HEADSET

FSA No.57E

STEM

Race Face Aeffect R (40mm)

HANDLEBAR

Race Face Era
SM(780x20)
MD(780x40)
LG/XL(800x40)

GRIPS

ODI Elite Flow Lock-On

SADDLE

SDG Bel Air 3 LUX

SEATPOST

OneUp Dropper Post
SM(150mm)
MD(180mm)
LG(210mm)
XL(240mm)

BRAKES

SRAM Maven Silver

ROTORS

SRAM Centerline (200/180mm)

SHIFTER

SRAM Eagle 90 MMX

DERAILLEUR

SRAM Eagle 90

CASSETTE

SRAM XS 1275 (10-52t)

CHAIN

SRAM GX Eagle Transmission

CRANK

RaceFace ERA Carbon E-MTB
(160mm)

CHAINRING

SRAM XX T-Type Direct Mount (32t)

CHAINGUIDE

Transition Integrated Top Guide

RIMS

DT Swiss XM 1700 Spline 30

SPOKES

DT Swiss Competition Race

HUBS

DT Swiss 350 Ratchet DEG 72 DF - Anti Kickback

TIRE/FRONT

Maxxis Assegai 3C MaxxGrip EXO+ (2.5)

TIRE/REAR

Maxxis Minion DHRII 3C MaxxTerra EXO+ (2.4)

INCLUDED

Bosch Charger, Tubeless Valves & Sealant

COLOR OPTIONS

	Anthracite
	Platinum

WEIGHT

41.4 lbs / 18.78 kg (Size MD)

Specs are subject to change at any time. All complete bikes are 95% assembled and packaged for quick and easy final assembly, and as such, Transition Bikes is not able to make special request build spec changes or modifications to packaging.

Ride Feel Focus

The dedicated mixed-wheel platform with 150mm rear and 160mm front travel make the Regulator SX nimble and responsive while delivering powerful assistance for the steepest of climbs.The Bosch SX system delivers the highest power-to-weight ratio possible. Perfect for riders who want lighter ride characteristics from their eMTB that excels in a wide variety of terrain.

Bosch Performance Line SX

Powered by the Bosch Performance Line SX system, the Regulator gets the legendary reliability of Bosch in a lightweight package giving you 60nm of torque and 600w peak power. While powerful, the system also provides an incredibly natural feel that delivers power without breaking traction, keeping your momentum and helping you clear technical trails.

Bosch 400wh Battery

Enclosed low in the downtube is Bosch's 400wh battery. Perfect for local laps where you want the most maneuverable eMTB in the market.

Bosch PowerMore Range Extender

Head into the backcountry with the additional 250wh range extender. Custom cable management keeps the connection clean and secure.

Display

Easily control the power modes and view battery life via the wireless Mini Remote and Bosch Kiosk 400c top tube display. This color display hosts a wealth of information from your bike's settings to stats from the ride.

Bosch Flow App

For those looking to dig into the settings, the Bosch Flow app gives you full control and customization. Once paired with your Regulator, you can adjust the power level support and peak power from the convenience of your phone without any wires or a laptop.

150mm rear, 160mm front travel with mixed wheels

The Regulator is all about making the most of every trail. Easily lay it over in turns, pop off every root, and zip your way back to the top for more. The mixed wheel platform, versatile geometry and 150/160 travel ensure you'll be having fun at all times.

LEVERAGE CURVES

The GiddyUp suspension system is built to deliver great performance without overthinking setup, so you can just grab your bike and ride. It uses a balanced 27% progressive leverage curve with consistent rate change, paired with tuned anti-squat for efficient pedaling and smooth acceleration. Moderate chain growth, which decreases after sag, helps keep suspension active without interference from chain tension.

On trail, this creates a ride that's supple off the top, supportive through the mid-stroke, and ramps up smoothly at the end, working well with both air and coil shocks. A wide 27 to 33% sag range lets riders fine tune the feel from playful to planted, all without needing to fuss with extra adjustments.

FEATURES

CLEAN CABLE ROUTING

Cable routing ports are compatible with 0, 1, or 2 cables and allow brakes to be run on either side.

CHARGE PORT

Our custom charge port door uses magnets to ensure it stays closed on even the rowdiest of descents.

INTERGRATED PROTECTION

While a preinstalled Loam Hat keeps dirt and debris away from your main pivot bearings.

INTEGRATED CHAINGUIDE

The sleek and effective top guide keeps the chain in place while being easy to open for maintenance.

"After a month of living with and riding the Regulator SX, I can proudly say that my opinion of electric mountain bikes has changed for the better. With the smaller 400-watt-hour battery and compact, lightweight SX motor, it barely looks or feels like an eMTB. This disguise even encouraged me to pedal it without assistance for a few 20+ mile rides, and I won't hesitate to do it again." - Deven McCoy Bike Magazine

FULL REVIEW

"The Regulator, in SX or CX trim, is an exceptionally fun and versatile ripper that rides less like an e-bike and more like a traditional mountain bike." - Shawn Spomer Vital MTB

FULL REVIEW

"Both versions prioritize handling and playful, natural ride quality over pure plow-and-smash capability. That said, these bikes are still very capableâ€”you could take them just about anywhere and have a good time." - Conor Barry Bikers Edge

FULL REVIEW

BIKE MAGAZINE VITAL MTB BIKERS EDGE

"The Regulator, in SX or CX trim, is an exceptionally fun and versatile ripper that rides less like an e-bike and more like a traditional mountain bike." - Shawn Spomer Vital MTB

FULL REVIEW

BIKE MAGAZINE VITAL MTB BIKERS EDGE

"The Regulator, in SX or CX trim, is an exceptionally fun and versatile ripper that rides less like an e-bike and more like a traditional mountain bike." - Shawn Spomer Vital MTB

FULL REVIEW

BIKE MAGAZINE VITAL MTB BIKERS EDGE

Speed Balanced Geometry
	SM	MD	LG	XL

A.REACH	425	455	480	510

B.STACK	623	632	641	651

C.EFFECTIVE TOPTUBE LENGTH	551	583	610	643

D.SEATTUBE LENGTH	375	400	440	470

E.EFFECTIVE SEATTUBE ANGLE	78.8	78.5	78.2	77.9

SADDLE HEIGHT FOR EFFECTIVE SEATTUBE ANGLE	600	660	720	780

ACTUAL SEATTUBE ANGLE	75	75	75	75

SEATTUBE OFFSET AT BOTTOM BRACKET	41	41	41	41

F.HEADTUBE LENGTH	105	115	125	135

G.HEADTUBE ANGLE	64.5	64.5	64.5	64.5

H.CHAINSTAY LENGTH	442	442	448	448

I.WHEELBASE	1201	1235	1271	1305

J.BOTTOM BRACKET DROP (FRONT)	25	25	25	25

J.BOTTOM BRACKET DROP (REAR)	5	5	5	5

K.ESTIMATED BOTTOM BRACKET HEIGHT	350	350	350	350

GENERAL SPECS
FRAME MATERIAL:	Carbon

WHEEL SIZE:	29" Front / 27.5" Rear

SIZES:	SM, MD, LG, XL

COMPONENT COMPATIBILITY
FORK OFFSET:	44mm

FORK AXLE-TO-CROWN:	579mm

HEADSET (TOP):	44mm Zero Stack

HEADSET (BOTTOM):	56mm Zero Stack

CHAINLINE:	55mm

REAR BRAKE MOUNT:	180mm Post Mount, Max Rotor Size 223mm

REAR AXLE:	Transition Axle For UDH, 12mm x 148mm Spacing

SEAT CLAMP:	37.0mm

SEATPOST DIAMETER:	31.6mm

SEATPOST INSERTION DEPTH:	Small 235mm \| Medium 260mm \| Large 300mm \| X-Large 330mm

TIRE MAXIMUM:	27.5” x 2.6" (*see FAQ)

SUSPENSION SPECS
FRONT TRAVEL:	160mm

REAR TRAVEL:	150mm (Compatible with 160mm)

SHOCK SIZE:	205mm x 60mm (compatible with 205 x 65mm)

SHOCK HARDWARE:	Trunnion Mount Top / 30mm x 8mm Bottom

SAG SETUP:	150mm/60mm: 16-20mm (26-32%)

BEARINGS:	2x 6903, 2x 6902, 6x 6802, 2x 6900

EBIKE SPECIFIC SPECS
DRIVE UNIT:	Bosch Performance Line SX (BDU31)

BATTERY:	Bosch CompactTube (400wh)

DISPLAY:	Bosch Kiox 400C

CONTROLLER:	Bosch Wireless Mini Remote

RANGE EXTENDER:	Compatible with Bosch PowerMore 250wh Range Extender (See FAQs Below)

OVERVIEW/BUY

BUILD SPECS

FEATURES

SBG GEOMETRY

REVIEWS

FRAME SPECS

FAQ'S

SUPPORT/SETUP

Ride Feel Focus

Bosch Performance Line SX

Bosch 400wh Battery

Bosch PowerMore Range Extender

Display

Bosch Flow App

150mm rear, 160mm front travel with mixed wheels

LEVERAGE CURVES

Ride Feel Focus

Bosch Performance Line SX

Bosch 400wh Battery

Bosch PowerMore Range Extender

Display

Bosch Flow App

150mm rear, 160mm front travel with mixed wheels

LEVERAGE CURVES

CLEAN CABLE ROUTING

CHARGE PORT

INTERGRATED PROTECTION

INTEGRATED CHAINGUIDE

Transition Regulator SX e-Mountain Bike

Ride Feel Focus

Bosch Performance Line SX

Bosch 400wh Battery

Bosch PowerMore Range Extender

Display

Bosch Flow App

150mm rear, 160mm front travel with mixed wheels

LEVERAGE CURVES

Ride Feel Focus

Bosch Performance Line SX

Bosch 400wh Battery

Bosch PowerMore Range Extender

Display

Bosch Flow App

150mm rear, 160mm front travel with mixed wheels

LEVERAGE CURVES

CLEAN CABLE ROUTING

CHARGE PORT

INTERGRATED PROTECTION

INTEGRATED CHAINGUIDE