If the interface between your freehub and the black sleeve ring on the axle is insufficiently lubricated, this cracking sound is the result.
Video Credit: Tacx B.V.
Root Cause
In broad terms, the root cause is that the Neo has not been sufficiently maintained. That is not to say that it’s due to negligence. Tacx recommends that the Neo freehub maintenance be performed annually, but this may be insufficient depending on the use. This audible sound is a very clear indicator that it’s past time to perform maintenance.
Steps To Resolve
- Use a 5mm Allen key to remove the nut from the end of the freehub.
- Remove the freehub from the Neo.
- Remove the black sleeve ring cylinder from the axle and apply grease inside and out.

Photo Credit: Tacx B.V.
- Place the cylinder back inside the free hub

Photo Credit: Tacx B.V.
- Install the freehub on the Neo
- Install the freehub nut and tighten until snug.
- If you have removed the cassette, reinstall the cassette and tighten to 40Nm
All information and media in this article are copyright of Tacx B.V. and have been duplicated here for the purpose of completeness.
What type of grease should be used when greasing the freehub?
I have Bike7 Mount Grease but not sure if this is suitable. Just looking for advice on type of grease please. Thanks in advance.
Phil
Hi Phil. I use Motorex 2000 bike grease. You can also use something slightly thinner, like Crystal.
I have similar issue but the sleeve cylinder is now worn. Can this be purchased separate, or does it come as part with the free hub,
Regards
Matt (UK)
Hi Matt. If you purchase a new freehub, it will also come with a new sleeve. If yours was able to wear, you should increase your inspection frequency to six months or fewer.