First Look | 2025 Transition Regulator with both Bosch CX and SX drive unit options

Transition has just announced the Regulator, a brand new e-MTB joining its lineup alongside the existing Repeater and Relay. The Regulator comes in two configurations: a full-power and a lightweight drive unit option, both powered by Bosch. Riders can choose between the Performance Line CX Gen 5 motor for maximum power or the Performance Line SX motor, which offers a lighter and less powerful alternative.

This marks a significant shift for Transition, as its previous e-MTBs relied on SRAM’s Powertrain and Fazua’s Ride 60 drive systems. The introduction of Bosch powered bikes is a first for the Bellingham based brand.

Known for its no-nonsense, fun-first approach, Transition designs bikes that prioritise an uncompromising descending experience. The Regulator looks to follow that same philosophy!

The Regulator, a do-it-all e-MTB with 150mm of rear travel (160mm compatible) and a 160mm fork.

2025 Transition Regulator overview

This Regulator platform aims to provide a true all round mountain bike that could comfortably be the only bike you own. If you’ve been keeping an eye on Transition lately, you’ve probably noticed the launch of the new Sentinel another do-it-all bike in its lineup. This bike bears a striking resemblance to the Regulator, even sharing some of the same colourways.

And you’re not wrong, there are plenty of similarities! The Regulator could easily been see as the e-MTB version of the Sentinel. Transition classifies the Regulator as an all-mountain bike, a term that faded for a while but is making a strong comeback. With its aggressive geometry, 150mm of rear travel, and a 160mm fork, it sits right between a trail and an enduro bike. Like its non-powered sibling, the Sentinel, you have the option to run a 65mm stroke shock to bump the rear travel up to 160mm.

One key difference? The new Regulator is designed exclusively for MX wheels, and running it as a full 29er isn’t recommended. Additionally, it will only be available with a carbon frame—no alloy option, at least for now.

In terms of weight, the Regulator holds its own against the competition. While it’s not the lightest bike out there, it’s far from the heaviest.

The SX and CX models share nearly identical platforms in terms of geometry and suspension travel, with the primary difference being the drive unit.

Drive unit options

Transition has fully committed to the Regulator platform, offering both a full-power and a lightweight version. With nearly identical frames, your choice ultimately comes down to the type of drive unit experience you prefer.

The higher powered models will use the Bosch Performance Line CX drive unit. This system delivers 85Nm of torque and up to 600 watts of peak power. Transition has opted for a 625Wh battery—not the biggest available, but it strikes a solid balance by saving a significant amount of weight. For those less concerned about weight savings -like we saw with the Santa Cruz Vala – many were hoping for a larger 800Wh battery.

For the lightweight version, the Bosch Performance Line SX drive unit provides 55Nm of torque and 600 watts of peak power, paired with a 400Wh battery.

Both models come with fixed batteries, so once they run out of charge, you can’t swap them on the fly or charge them off the bike. If you need extended battery life, both Regulator models are compatible with an optional 250Wh range extender, which is available for purchase separately. It could also be inconvenient when travelling with the bike, especially if you need to remove the battery for a flight. On the positive side, it has a sleek design and helps reduce overall weight.

For a deeper dive into these drive units, check out the articles below.

Related:

The Bosch SX drive unit delivers 55Nm of torque and is paired with a 400Wh battery, while the CX drive unit offers 85Nm of torque with a 625Wh battery.

Transition Regulator geometry & size chart

Both the CX and SX versions of the Regulator will be available in four sizes: S, M, L, and XL. On the CX models, reach ranges from 420mm (S) to 510mm (XL), while the SX versions start slightly longer at 425mm, extending to the same 510mm on the XL. The slight geometry differences come down to the full-power CX model featuring a geo adjust flip chip, whereas the lighter SX version does not.

One standout detail is the size specific chainstays, particularly on the SX models. Many competitors using Bosch’s SX drive unit stick with a fixed 450mm rear centre across all sizes, citing design challenges in shortening the chainstays around the SX drive unit. However, Transition has managed to overcome this, offering size specific rear centre lengths on all Regulator models.

Transition Regulator price and specs

Coming to Australian shores are two build kit options for each of the Regulator CX and SX versions. The lower spec models are starting at $12,499 AUD for the Regulator SX Deore. The Regulator CX Deore build will be $12,999 AUD. For the higher spec models, those will feature Shimano XT build kits. The Regulator SX XT comes in at $14,499 AUD and the Regulator CX XT version will be $14,999 AUD.

Transition Regulator
Transition Regulator CX Deore Salish Sea Blue

Transition Regulator CX Deore

Transition Regulator
Transition Regulator CX XT Glacier White

Transition Regulator CX XT

Transition Regulator
Transition Regulator SX Deore Stormshadow Grey

Transition Regulator SX Deore

Transition Regulator
Transition Regulator SX XT Madrone Gold

Transition Regulator SX XT

Transition e-MTB cheat sheet

With these new additions, Transition’s e-MTB lineup has expanded into a diverse range of four distinct models, each featuring a unique drive unit. To help you navigate the lineup, we’ve created a cheat sheet outlining the key stats and features of each model. Below, we compare the two lightweight options: Relay and Regulator SX. Additionally, we pit the two full power models, Repeater PT and Regulator CX against each other.

Relay VS Regulator SX

Relay (left) & Regulator SX (right)

Repeater PT VS Regulator CX

Repeater PT (left) & Regulator CX (right)
With the addition of the new Regulators, Transition now offers four motor options from three different brands-Bosch, Fazua & SRAM.

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