Gates SureFit Tool
The Gates SureFit Tool is the installation tool for SureFit sprockets: it lets you fit them firmly without damaging the hub or the sprocket’s flexible fingers. The tool is not required, but it makes fitting easier and quicker, especially in a busy workshop.
Why choose this tool?
Protects the hub. Fits SureFit sprockets firmly without damaging the hub.
Protects the fingers. Does not damage the flexible fingers of the SureFit sprocket.
Quick fitting. Makes fitting easier and quicker, especially in high-volume workshops.
For all SureFit sprockets. Made for the SureFit interface of the Gates sprockets.

What is SureFit?
SureFit sprockets have a flexible finger design and a slight interference fit, which gives the best installation on internally geared hubs. Make sure the sprocket and its snap ring are fully seated and click into place.

Fitting and removing sprockets
The SureFit Tool fits SureFit sprockets. To remove 9-spline and Bosch sprockets use the Gates Strap Wrench, and for the sprocket lockring of the S550 crankset use the Locknut Tool.
Technical data
| Property | Value |
|---|---|
| Type | Installation tool |
| Fits | SureFit sprockets |
| Made for | Bike shops and assemblers |
Which Gates tool for which job?
| Gates tool | Job |
|---|---|
| Spring Tension Tester | Checks belt tension |
| Sonic Tension Meter 350C | Checks belt tension |
| Sonic Tension Meter 550C | Checks belt tension |
| Belt Tension Meter PCE-BTM 2000 | Checks belt tension |
| Rear Belt Liner | Checks alignment |
| Laser Belt Liner V3 | Checks alignment |
| Frame Alignment Kit | Checks the frame |
| SureFit Tool (this tool) | Fits sprockets |
| Strap Wrench | Removes sprockets |
| Locknut Tool for S550 | Fits sprockets |
| RDM Snubber | Protects the belt |
| Snubber Screw | Protects the belt |
| Snubber Spacer Kit | Protects the belt |
| Belt Care Silicone Spray | Cares for the belt |
| Tensioner Idler Wheel | Replaces a part |
Frequently asked questions
Do I have to use the SureFit tool?
No. A SureFit sprocket can be fitted without the tool, but the tool makes fitting easier and quicker and protects the hub and the fingers.
Which sprockets are SureFit sprockets?
SureFit sprockets are the 3-lobe sprockets for internally geared hubs, for example for Shimano Alfine and Nexus hubs; see our CDX, CDC and CDN SureFit rear sprockets.
Do I need special tools for a belt drive?
A belt drive needs far less than a chain, but the right tension and alignment matter. Gates offers tools for checking tension, checking alignment, fitting sprockets and protecting the belt – see the table above, and ask us which ones suit your bike.
What do CDX, CDC and CDN mean?
They are Gates’ three belt-drive lines for bicycles: CDX (top of the range), CDC (mid-range) and CDN (entry level). Gates rates CDX for hub motors and mid-drive e-bike motors up to 120 Nm, CDC for mid-drive motors up to 75 Nm, and CDN for hub-motor e-bikes and casual riding. The tools here work with all Gates Carbon Drive parts.
About Gates Carbon Drive
Gates Corporation has been a global leader in power transmission and belt drive technology since 1911. In 2007 it launched the first belt drive system for bicycles, and today more than 1,000 bike brands worldwide use Gates Carbon Drive, from city and trekking bikes to e-bikes, cargo and mountain bikes.
On the bike

