Bulls Sonic AM: suspension setup & specs
The Bulls Sonic AM is an e-MTB for trail and touring with 150 mm of fork travel and 140 mm at the rear. It is powered by Bosch Performance Line CX GEN5 (Smart System) 25/85 Nm. Here you will find all 4 current builds with fork, shock and shock size, plus matching SAG and tyre pressure starting values.
Calculate the setup for your Bulls Sonic AM →
All builds
Fork, shock, shock size (eye-to-eye length × stroke) and rear travel, motor, weight and price according to the manufacturer. Wheel size: 29.
| Build | Fork | Shock | Shock size | Rear travel | Motor | Weight | RRP | Calculator |
|---|---|---|---|---|---|---|---|---|
| 1 | SR Suntour ZERON 36 Air (150 mm) | RockShox Deluxe Select+ RL | – | 140 mm | Bosch Performance Line CX GEN5 (Smart System) 25/85 Nm | 25.9 kg | €5,799 | Setup → |
| 2 ABS | SR Suntour ZERON 36 1.8 Air (150 mm) | RockShox Deluxe Select+ RL | – | 140 mm | Bosch Performance Line CX GEN5 (Smart System) 25/85 Nm | 26.7 kg | €5,999 | Setup → |
| 3 | RockShox Lyrik Base (150 mm) | RockShox Deluxe Select+ RL | – | 140 mm | Bosch Performance Line CX GEN5 (Smart System) 25/85 Nm | 24.9 kg | €6,999 | Setup → |
| 4 ABS | SR Suntour AION 36 Air ABS (150 mm) | RockShox Deluxe Select+ RL | – | 140 mm | Bosch Performance Line CX GEN5 (Smart System) 25/85 Nm | 25.8 kg | €7,199 | Setup → |
How it compares
On travel, the Bulls Sonic AM is right where the “e-MTB for trail and touring” category usually is: 150 mm up front against a median of 150 mm from 101 bikes. The fork has 10 mm more travel than the rear end with 140 mm – a common layout that takes load off the front on steep terrain. On travel, it slots in between the Bulls Sonic EVA AM SX and the Bulls Copperhead EVO AM in the Bulls range. The frame is made of carbon.
Bulls quotes 24.9 kg for the 3 build; that is 1.5 kg more than the 23.4 kg median of 49 comparable bikes. Within the range, weight varies by 1.8 kg. The starting price of €5,799 (1) is roughly in line with the category median (€5,500). The top build, 4 ABS, costs €7,199. Depending on the build, fork and shock come from RockShox and SR Suntour. In total, 4 different forks are used, from the SR Suntour ZERON 36 Air to the SR Suntour AION 36 Air ABS. Drive comes from Bosch Performance Line CX GEN5 (Smart System) 25/85 Nm. Worth knowing for heavier riders: the maximum system weight is 150 kg – after about 27 kg of bike, that leaves around 123 kg including kit.
Setup notes for this spec
- Fork (RockShox Lyrik Base): air goes in through the valve on top of the left leg. After every change, compress the fork firmly a few times before measuring SAG.
- Rebound: turn the red RockShox adjuster fully closed first and count clicks from there – that way you can note settings and restore them later.
- Air shock (RockShox Deluxe Select+ RL): measure SAG in your riding position, ideally with a helper holding the bike. Cycle the shock a few times after every pressure change.
- e-MTB: the extra weight mainly affects tyre pressure, which is why the table below already includes a surcharge. SAG is measured just as on a bike without a motor.
Target SAG for the Bulls Sonic AM
The table converts the recommended SAG percentages into millimetres, so you can check them with the O-ring directly on the stanchion and on the shock shaft. Adjust the air pressure until the value is right. If Bulls specifies its own target SAG for your model, that takes priority.
150 mm fork (all builds)
| Riding style | Fork SAG |
|---|---|
| XC / touring | 17 % = 26 mm |
| Trail | 20 % = 30 mm |
| Enduro / rough | 22 % = 33 mm |
| Bike park | 20 % = 30 mm |
How to measure SAG is explained in our guide SAG setup.
Tyre pressure starting values
Basis: 2.40″ tyre width, tubeless, trail casing, including the e-MTB surcharge. If you run tubes, add about 0.2 bar (2.9 psi); with an insert, about 0.1 bar (1.5 psi) less is enough. Stock tyres: SCHWALBE Magic Mary EVO; SCHWALBE Magic Mary Performance black; SCHWALBE Magic Mary Performance black bronze.
| Ready-to-ride weight | Front | Rear |
|---|---|---|
| 60 kg | 1.48 bar (21 psi) | 1.68 bar (24 psi) |
| 70 kg | 1.60 bar (23 psi) | 1.80 bar (26 psi) |
| 80 kg | 1.72 bar (25 psi) | 1.92 bar (28 psi) |
| 90 kg | 1.84 bar (27 psi) | 2.04 bar (30 psi) |
| 100 kg | 1.96 bar (28 psi) | 2.16 bar (31 psi) |
| 110 kg | 2.08 bar (30 psi) | 2.28 bar (33 psi) |
| 120 kg | 2.20 bar (32 psi) | 2.40 bar (35 psi) |
Air pressure in the fork and shock
You will find a guide value for air pressure on the fork sticker (or on the shock) or in the suspension makers’ charts. Our calculator also takes riding style and rebound into account. In the end, measured SAG is what counts.