Specifications
Full technical breakdown of the OX 2.0 MTB 1x12 full groupset and the 4-piston hydraulic disc brakes.
What's in the Box
×1
OX 2.0 Wireless Electronic Rear Derailleur (93mm Long Cage)
×1
Wireless Button-Style Shifter
×1
EVOSID MTB Crankset — arms, 29mm spindle and direct-mount chainring (length, size and color as selected)
×1
EVOSID BC1.37"×24T Bottom Bracket + Spacers
×1
SUNSHINE-SZ 12-Speed 11-50T Cassette
×1
CHOHO Z12-DSL 12-Speed Chain, 128 Links + Quick Links
×1
Magnetic Charging Cable
×1
Type-C Adapter
×1
Special Tailhook Backup Washer
×1
Quick-Start Guide
Braking
×1 Pair
BR-MA3000 4-Piston Calipers (front + rear)
×2
BL-MA3000 Hydraulic Brake Levers (left + right, interchangeable)
Pre-Installed
Cooling-Fin Brake Pads
×2
180FP-M Post Mount Adapters
×3
Brass Hose Olives
×3
Insert Pins
×3
Hose Compression Fitting Bolts
×4
Caliper Mounting Bolts
×1 Set
Hydraulic Hoses — Front 90cm + Rear 160cm
Check Your Derailleur Hanger
Please complete these two checks before fitting the WHEELTOP rear derailleur. Only install it once both are confirmed.
Is the Hanger Straight?
A bent hanger tilts the rear derailleur, which causes poor shifting, chain noise and difficult calibration, no matter how carefully it is set up.
How to check: look from behind the bike. The hanger should hang straight down, parallel to the cassette cogs. If it is bent, straighten it with a hanger alignment tool or fit a new hanger.
Does the Hanger Have a Step?
Clear step at the bottom
Very small step
The small tab next to the mounting bolt must rest on the step at the bottom of the hanger, so the derailleur can swing forward and back.
Small step? Fit a hanger with a larger step, or a derailleur hanger extender. Otherwise the derailleur stays rigid and cannot be set up.
Not sure? Send us a close-up photo of your hanger through eBay messages before ordering, and we will check it for you.
Compatibility & Buyer Notes
Please review the following before purchasing to ensure correct fitment.
UDH Frames: Mounts on the Existing Hanger, No Extra Parts
This is a standard hanger-mount derailleur, not a hangerless direct-mount like SRAM Transmission — so if your frame uses a UDH hanger, leave it in place and bolt the derailleur straight onto it, no adapter needed. WHEELTOP lists UDH frames as "partially compatible" because on a small number of frames, the derailleur body can lightly interfere with the frame near the smallest cog. After installing the chain, shift to the smallest cog and check by hand for any rubbing before fine-tuning limits in the app.
1x Drivetrain Only
Designed for single-chainring setups. Not compatible with double or triple chainring systems due to direct-mount structure.
Boost Chainline (52mm)
The chainring sits on a 52mm Boost chainline, made for frames with a Boost 148mm rear hub. It will fit an older non-Boost frame, but the chain runs at a steeper angle in the largest cogs, so we don't recommend it.
App-Based Setup Required
Initial calibration must be performed via the WHEELTOP app (free on iOS and Android) after installation.
Bottom Bracket and Freehub
The included bottom bracket fits BSA threaded shells 68-73mm wide (not press-fit). The cassette needs a Shimano HG freehub body — it does not fit SRAM XD / XDR or Shimano Micro Spline.
Post Mount Frames Only
This caliper is designed for direct-mount (Post Mount) mountain bike frames and forks. It does not fit Flat Mount road/gravel frames — confirm your mount type before ordering.
Ships as Separate Components
The brake lever and hose ship unassembled from the caliper. Routing the hose and connecting the fitting is a specialized process — we recommend having it installed and bled by a professional bike shop.
Brake Pads Are a Wear Item
The brake set carries a 1-year warranty; brake pads are a consumable wear part and are not covered. Check pad wear regularly, and check for low fluid or air in the line — top up mineral oil as needed.
Disc Rotors Not Included
The brake set includes the levers, calipers, hoses, pads and Post Mount adapters, but no rotors. The calipers work with 140 / 160 / 180 / 203mm rotors, 1.8–2.2mm thick.
Thank you for visiting our listing. If you have any questions before purchasing, please send us a message through eBay and we'll respond within 24 hours.


























