CYC Photon Pro vs Photon 2: Differences, Specs and Which to Choose
Quick answer: The CYC Photon Pro doubles the Photon 2's peak power (4000W vs 2000W) and raises max torque from 135 to 180 Nm. It costs about 1 kg more weight (4.5 vs 3.5 kg) and $148 more ($1,098 vs $950). Pick the Photon 2 for lighter, street-legal, pedal-first builds. Pick the Photon Pro for steep off-road climbing, cargo and private-land performance builds.
Spec source: cycmotor.com product pages for Photon Pro and Photon 2, checked October 10, 2026. Prices in USD.
Both are CYC mid-drive conversion kits. They bolt into the bottom bracket of a standard bicycle, use a torque sensor, and run on the same 36V to 72V battery range. The question is how much power, weight and money you want to put into the build.
A note on names: the "CYC Photon Pro" in this article is a conversion motor. It is not the Zen Photon Pro, a complete e-bike from a different brand that uses a different motor.
The two Photons, side by side
Same torque-sensing platform, same batteries and chainrings. The difference is power, weight and where you can legally ride.
CYC Photon 2
Street-legal commuting, gravel and Class 1 trails
750W nominal, 2000W peak, 135 Nm, 3.5 kg
Kit $950 · Photon 2 + A-52 battery $1,338
CYC Photon Pro
Steep off-road climbs, cargo and private land
3000W rated, 4000W peak, 180 Nm, 4.5 kg
Kit $1,098 · Photon Pro + A-52L battery $1,636
Side-by-side specs
| Spec | CYC Photon 2 | CYC Photon Pro |
|---|---|---|
| Rated power | 250W / 750W | 3000W |
| Peak power | 2000W | 4000W |
| Max torque | 135 Nm | 180 Nm |
| Voltage | 36V to 72V | 36V to 72V |
| Max cadence at crank | More than 300 RPM | More than 300 RPM |
| Total weight | 3.5 kg (7.7 lb) | 4.5 kg (9.9 lb) |
| Controller | VTON (generation) | VTON Gen 2 |
| Pedal sensing | Torque sensor | Torque sensor |
| Motor chainrings | 32T, 34T, 36T, 38T, 40T, 42T, 50T | 32T, 34T, 36T, 38T, 40T, 42T, 50T |
| Bottom bracket fit | BSA 68 to 83 mm, BB92, BSA 100 mm, BSA 120 mm | BSA 68 to 83 mm, BB92, BSA 100 mm, BSA 120 mm |
| Display | Intuition, 2.1 in color, IP65 | Intuition, 2.1 in color, IP65 |
| App | Ride Control (Bluetooth) | Ride Control (Bluetooth) |
| US Class 1/2/3 configurable | Yes, per CYC FAQ | No, per CYC FAQ |
| Kit price | $950 | $1,098 |
Read the table this way. Torque, peak power and weight are the three real differences CYC publishes. Voltage, cadence, chainrings, bottom bracket fit, display and app are the same on paper.
What is different
Power and torque
The Photon Pro is rated at 3000W continuous with 4000W peak. The Photon 2 is sold as a 250W or 750W rated motor with 2000W peak. CYC's Photon Pro launch post positions the extra output for "steep trails or when transporting heavier loads."
Torque goes from 135 Nm to 180 Nm, a 33% increase. Torque is what you feel on a steep climb from low speed and when starting a loaded cargo bike. Peak power is what holds speed once the hill gets long.
We are not publishing top speed figures for either motor. Speed depends on battery voltage, chainring, cassette, wheel size, rider weight and firmware limits, and CYC has not released a tested number for either kit.
Weight
CYC lists 3.5 kg for the Photon 2 and 4.5 kg for the Photon Pro. That is 1 kg (about 2.2 lb) more at the bottom bracket. CYC does not state whether these figures include cranks, chainring or the torque sensor, so compare them to each other, not to other brands' motor-only weights.
Controller and motor internals
CYC describes the Photon Pro as "VTON Gen 2 & Redesigned Motor." The launch post says the Pro "unlocks the full potential of the VTON controller."
Here is what CYC has not published: what changed inside the motor. We do not know if the Pro uses a different stator, rotor, gear reduction, cooling path or clutch. We also do not know the phase-current limit of either controller.
What we do know is how the Photon 2 is built. CYC's Photon 2 engineering post covers it:
- Inrunner motor with flat-wire windings and an epoxy-potted core (Gen 1 was an outrunner)
- 20x28 mm sprag clutch, up from 12x20 mm on Gen 1
- Drive unit opens with four M5 bolts; controller, torque sensor, motor module and first stage are separately replaceable
- Full CANBUS electronics
Whether the Pro carries all of these forward is not confirmed.
Small parts that differ
CYC's parts catalog sells separate bash guard sets for the Photon 2 and the Photon Pro, so the housings are not identical at the front. The torque sensor assembly in the catalog is listed for the Photon 2 only.
What both share
Several parts in the CYC catalog are labeled for both motors:
- Chainrings. The 32T to 42T chainring sets are sold as "Photon 2 / Photon Pro." On the Photon 2, 36T to 50T rings keep a 52 mm chainline and the 32T and 34T rings use a 7 mm offset. The chainring guide explains how to pick a size. A common pick is the 42T Photon chainring.
- Speed sensor. The magnetic speed sensor is listed for both.
- Bottom bracket fit. Both product pages list BSA 68 to 83 mm, BB92, BSA 100 mm and BSA 120 mm. CYC's conversion kit FAQ adds that PF30, BB30 and T47 frames work with a press-to-thread sleeve, and that Trek BB90/BB95 frames are not compatible.
- Display and app. Both use the Intuition display and the Ride Control app over Bluetooth.
- Batteries. CYC states its A-series packs are compatible with all CYC mid-drive systems.
Who should buy which
| If you ride... | Choose | Why |
|---|---|---|
| Road, gravel or commuting on public roads | Photon 2 | Sold in 250W and 750W rated versions and configurable to Class 1, 2 or 3 limits |
| Mostly pedaling, want a light bike | Photon 2 | 1 kg lighter, same torque-sensing feel |
| Trail and eMTB on private land | Photon Pro | 180 Nm and 4000W peak for steep, sustained climbs |
| Cargo bike or heavy rider and load | Photon Pro | More torque for loaded starts on grades |
| Budget-limited first build | Photon 2 | $148 less for the kit |
| Unsure, but frame and riding may change later | Photon Pro (off-road) or Photon 2 (road) | Decide by where you will legally ride it |
Commuting and road
For riders on public roads, the Photon 2 is the more practical choice. CYC's own FAQ calls it "the right choice for street-legal riding." The rated power options match US Class limits, and the Ride Control app lets you set power and speed caps. The lower weight also helps when you are pedaling with assist off or carrying the bike.
eMTB and steep climbs
On private land or off-road trails where higher power is allowed, the Photon Pro's extra 45 Nm and doubled peak output give more headroom on steep pitches. Expect more load on your chain and cassette at these power levels. Plan your drivetrain with that in mind.
Cargo and heavy riders
Torque at the crank matters most when starting a loaded bike on a hill. The Pro has the higher figure. If the cargo bike will be ridden on public roads, check the legal question below first, because the Pro is described by CYC as exceeding Class limits.
Battery pairing and bundle prices
Both motors accept 36V to 72V packs. CYC sells each motor in a bundle with its A-series batteries. See all packs in the battery collection and the battery buying guide.
| Battery | Pack spec | Photon 2 bundle | Photon Pro bundle |
|---|---|---|---|
| A-52 | 52V, 520Wh | $1,338 (Photon 2 + A52) | $1,486 |
| A-52L | 52V, 780Wh | $1,488 | $1,636 (Photon Pro + A52L) |
| A-65 | 65V, 1300Wh | $1,946 | $2,094 |
All bundle prices. CYC does not publish range figures for these packs, so we do not quote any.
Legal power settings
In the US, Class 1, 2 and 3 e-bikes are generally limited to 750W nominal. CYC's FAQ says the Photon 2 can be set within Class 1, 2 or 3 limits in the Ride Control app. It says the Photon Pro "exceeds Class limits" and is intended for private land and off-road use.
One dealer lists the Photon Pro with 250W and 750W firmware versions. CYC has not confirmed this on its own site. Until CYC confirms it, treat the Pro as an off-road motor. State and local rules vary, so check yours.
Can you upgrade from Photon 2 to Photon Pro?
You can buy a Photon Pro and reuse parts that CYC lists for both motors: chainrings, the speed sensor and the battery. The Intuition display is listed on both product pages. CYC has not published a full carry-over list for the harness, torque sensor or bottom bracket hardware. Ask CYC support with your exact setup before you order.
Verdict
If you want one rule: decide by where you will ride. Public roads and pedal-first riding point to the Photon 2. Private land, steep terrain and heavy loads point to the Photon Pro.
The Pro buys you 45 Nm and 2000W of extra peak power. It costs 1 kg and $148. Chainrings, speed sensor, battery, display and app are shared; the bash guard is not.
FAQ
What is the difference between the CYC Photon Pro and Photon 2?
The Photon Pro has 180 Nm of torque and 4000W peak power. The Photon 2 has 135 Nm and 2000W peak. The Pro weighs 4.5 kg vs 3.5 kg and costs $1,098 vs $950. Voltage range, chainring options, bottom bracket fit, display and app are the same.
Is the Photon Pro worth the extra cost?
It is worth it if you ride steep off-road terrain, haul cargo, or build a private-land performance bike. For commuting and road riding within US Class limits, the Photon 2 does the job for $148 less and 1 kg less weight.
How much does the Photon Pro weigh?
CYC lists the Photon Pro at 4.5 kg (9.9 lb). Some dealer listings show 5.6 kg. CYC's product page is the reference value.
Do Photon 2 chainrings fit the Photon Pro?
Yes. CYC sells its 32T to 42T chainring sets as "Photon 2 / Photon Pro," so the same rings fit both motors.
Can the Photon Pro be set to 750W or 250W for street-legal use?
CYC's FAQ describes the Photon Pro as exceeding US Class limits. One dealer mentions 250W and 750W firmware versions, but CYC has not confirmed this. If you need a Class-legal build, the Photon 2 is the confirmed option.
Which Photon is better for cargo bikes?
The Photon Pro, for torque. It has 180 Nm vs 135 Nm, which helps loaded starts on hills. If the cargo bike is used on public roads, the Photon 2 is the option CYC confirms can be set to Class limits.
Is the CYC Photon Pro the same as the Zen Photon Pro?
No. The CYC Photon Pro is a mid-drive conversion kit you install on your own bike. The Zen Photon Pro is a complete e-bike from another brand with a different motor.
