TACX Cog stuck on cassette

Did you remove the lock ring on the cassette? You don't need to remove the freehub body (the part you have circled) to change the cassette.  I'd recommend installing that assembly back on the trainer and then use a lockring tool to remove the lockring and then the cassete cogs should come off.  Sometimes cassettes can bite into the material of the freehub making removal a little more difficult, but they come free with a little wiggling.

Hi Patrick, thanks for the fast repsonse!

I can't get the lock ring off at all, it is completely stuck 

Did you use a torque wrench to tighten the lock ring to the correct torque value when you installed the cassette? Over tightening the lock ring is a common cause of them seizing.

Try a long handled 'breaker bar' so you can get sufficient mechanical advantage to release the lock ring. If it is really tight it may require the assistance of another to hold cassette tool for you while you try to turn the lock ring.

Hi! Thanks for getting back!

I went to a bike shop yesterday, to reinstall the cassette. The guy needed a pipe at the edge of the torque wrench to extend the torque arm, but finally cassette was loose. I have a 11-30 Shimano cassette, exactly the same model on my bike. He said the outer ring does not fit, so he installed the cassette with 10 rings +  1 spacer - it is working fine now, but I wonder if that was the right solution. Doesn't the default frame mount on neo 2 SE fit 11-30 cassette?

having the exact same problem on my tacx flux 2 s. I have a masters degree in mechanical engineering but seriously don't understand what you are talking about. Please provide a step-by-step explanation with pictures please.

Hi guys,

For feedback on my side, it just needed some extra force, one of my strong friends came round and helped remove it for me 

10 speed Shimano/SRAM cassettes require the included spacer on the inside.  11 speed cassettes do not. 

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