7 speed moutain bike SLIPPING on Tacx Neo 2t, help for a complete beginner

Hi all,

I have a hybrid bike that I am desperately trying to setup properly on a Tacx Neo 2t. The bike is 7-speed, the chain, the cassette, the derailleur - all 7-speed. I know that tacx says the unit is compatiable for 9, 10 and 11 speed. I don’t have this kind of bike.I bought a Shimano Ultegra R8000 11 Speed Cassette with my Neo because I thought this might work.

And it did. For a while, the 7 speed bike worked with the 11 speed cassette. Of course, some gears felt weird but i could actually use the trainer. Then, I tried climbing something for a long time. It was loud but the bike had just detached from the freehub. So i just fixed it on again but the chain since this ordeal keeps on slipping and sliding. The chain is holding onto the casette very poorly and keeps slipping. There’s no way i can use this trainer like this.

What are my options? Is this beyond help?

Grateful for all advice.

The bike i own: https://www.halfords.com/bikes/hybrid-bikes/apollo-belmont-mens-hybrid-bike—18in-21in-frames-566619.html

all sorts of mistakes here. the chain is probably too thick, alignment is incorrect.

Use a 7 speed cassette and 2 spacers. A 4.5mm spacer and a 1.8mm spacer. Use them together. That will be the appropriate placement.

You said MTB. Are you a 135mm or 130mm wide rear? Use the appropriate adapters. You might be 135mm.

Also, your bike may be a freewheel. But, for the trainer, just buy a 7 speed cassette.


If it’s in the state most 7 speed hybrids are, the chain’s probably at 2% stretch (aka worn beyond all hope) - luckily 7 speed chains are dirt cheap!


I am a complete noob. Thank you so much for the advice, just ordered a 7-speed cassette and will try this out. it’s so weird… it was working OK until i climbed on the regular. Urgh. Probably f’d the chain aswell.

Thanks though wish me luck!

i probably f’d the chain like an idiot. It was fine until i started climbing on the regular. I just bought a 7 speed cassette and will see if that works. I only discovered bike gears were a thing 2 weeks ago so i think a chain switcheroo situation cannot happen. It should be illegal for me to be able to do that to any bike.

Yeah if you don’t have an 11 speed bike, just a 7 speed cassette and chain will fix the problem, then it should work inside and outside. You can likely sell the cassette, although it may be damaged by now.

I’ll keep the cassette. Might need it for a nice bike in the future. Hoping my love for indoor cycling will translate to outdoors someday :smiley:

Good luck! Do not forget the spacers. You need a 4.5 mm and a 1.8mm.

The Neo, oddly comes with a 1.0mm spacer

1.8mm + 4.5mm is what you need.

Hi iamholland

can you clarify which side of the cassette the 4.5mm should go on?


Between the Neo and the cassette. The gears are always closest to the derailleur.

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does that mean both the 4.5mm and 1.8mm are stacked together between the neo and cassette… or the 1.8m goes nearest the derailleur?

yes, that’s what it means.

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