Rohloff Monkey Bone 160 mm – IS to PM adapter
The Rohloff Monkey Bone 160 (8553) combines torque support and IS-to-post-mount brake adapter: it anchors a SPEEDHUB 500/14 with OEM2 axle plate on an IS2000 frame mount and carries a post-mount caliper for a 160 mm rotor.
Why the Monkey Bone?
Torque arm and brake adapter in one. No long torque arm on the chainstay – the hub torque goes into the frame through the brake mount. 
Approved for e-bikes and tandems. Rohloff only permits OEM2 mounting on e-bikes and tandems together with a Speedbone, Monkey Bone or PM Bone. 
For 160 mm rotors. Use it with a post-mount caliper and a 160 mm rotor. 
Clean installation. The OEM2 axle plate drops into the recess every time the wheel goes in.
Who is it for?
- Touring and trekking riders. A neat, strong torque support for disc-brake SPEEDHUB bikes.
- E-bike and tandem owners. One of the torque supports Rohloff permits for OEM2 hubs in these bikes.
- Riders retrofitting a SPEEDHUB. For frames with an IS2000 rear brake mount.
Compatibility
| Hubs | SPEEDHUB 500/14 with OEM2 axle plate: O.L.D. 135, 142, 148, 170 and 177 mm |
|---|---|
| Frame brake mount | IS2000 (International Standard) |
| Brake caliper | Post mount |
| Rotor size | 160 mm |
| Bolts | Not included: frame M6x18–20 and caliper M6x16 bolts (usually supplied with the brake) |
| Torque | 6 Nm (frame and caliper bolts) |
| Not compatible | IS calipers; frames with integrated/direct post mount |
Frequently asked questions
Does the Monkey Bone fit a frame with direct post mount?
No. It needs an IS2000 brake mount on the frame. For direct post-mount frames Rohloff offers the PM axle plate with PM Bone.
Is it safe with a quick-release axle?
With CC/TS axles the anchoring point must sit behind a line parallel to the dropout slot through the axle; otherwise the torque could turn the axle out of the dropout. With A12 thru axles this check is not needed.
Do I need frame approval?
Rohloff permits OEM2 mounting only on frames approved for it by the frame maker; otherwise it is at your own risk. We can help you check your frame.
About Rohloff
Rohloff AG designs and builds the SPEEDHUB 500/14 in Fuldatal, Germany: a 14-speed gear hub with a 526% gear range that has proven itself for more than 20 years on touring, tandem, cargo and e-bikes.
BoodaBike (Massive Bikes, Budapest) is an official Rohloff service centre, trained by Rohloff, and an official European distributor of Rohloff hubs and genuine spare parts. Not sure which part fits your hub? Send us the serial number and a photo of your hub and we will check it for you.