NEO 2T Issues with cassette alignment and low pitched rumble/grinding in high gears

Update, the spacer bends against the bottom of the cassette when torqued causing it to spin off axis. Ghetto fix has been to install it behind the hightest gear instead and although not ideal at least it works.

However,

There is a noticeable low pitched grinding sound at higher gears, very obviously different to usual drivetrain noise. This is different to the higher pitched grinding (https://tacxfaqx.com/knowledge-base/grinding-sound/) Also the pedal stroke is not smooth, resistance feels varies at different stages of the stroke.

Nothing but trouble from this unit so far...

  • Hi,

    I have this problem, my neo2t seem perfect , I have two 1 mm spacer for my Shimano 10 Speed Ultegra Cassette 6700 11 -28 T

    In the smallest rear gear ( highest speed, smallest Cog ) It make a " grinding noise " and i feel it in the pedale and i have a vibration in the bike.

    https://1drv.ms/v/s!AnG9XeXziTQJpTG8jjdgYiUtM7Hi?e=ykt7CI

    All other gear are ok.   I made a supprot request at garmin and they send me a new FreeHub, I will have it next week, but me freehub is alresdy new, I have my brand new Neo2T since last week and I have this sound.  Its not the Road Feel option, Its not chain rub.  I realign my rear derailleur, etc.…

    Thanks !

  • i even called support and they told me i had it adjusted wrong and i should fix the derailleur alignment after sending them a video.

    I ended putting this on. https://velo-orange.com/products/problem-solvers-10-speed-to-11-speed-spacer  it got me closer but still not perfect.

  • Same issue on mine - rumbling/low pitched vibrations from trainer, feeding back into pedals. Occurs at certain load/rpm (180-250W, 65-85rpm range). Really annoying. Seems it's the finite number of magnets in the brake moving over the coils, generating a stroing ripple in the torque response. What a flawed desing for a dreict drive! :-( Garmin, any firmware upgrades which could fix this? Thinking about returning my unit - it's a massively overpriced piece of crap like it is now... :-(

    PS: Before I receive any response about 'it's your drivetrain/bike': I have changed chain, cassette, derailleur, chainring now, one by one. ISsue stays the same, it's the Neo 2T 100% affirmative!

  • I also have this problem. I wonder if this is because some bikes are not compatible with the Neo.  I have to use the left spacer to prevent my discbrake from rubbing against the case and readjust my Di2 from my normal setup to prevent the derailleur from rubbing agains the flywheel, so the setup is not really the same as my normal bike setup.

  • Bit of a necro-post here but wanted to add to this discussion.

    I have a NEO 2T bought this summer that I’ve used with two bikes - one was a bike from 2009 “performance hybrid”, the other a 2020 Giant Contend 1.

    Older bike with 135mm QR spacers installed: perfect.

    Newer bike with 130mm QR spacers: rumble.

    The latter also seemed to require a thicker spacer behind the 9-speed cassette (the 2mm where the other seemed happiest with the 1mm.

    Ergo, I’m with ACH here wondering if some bikes just don’t “play nice” with a NEO 2T or require a lot of fiddling to get running smoothly.

  • Similar experience here with a 2018 Eddy Merckx 525 with Shimano Ultegra disc brakes, 142mm thru axle.

    I’ve tried ways to fix my bike to the Neo 2t: with the recommended 2.7mm spacer (T2844.15) on the Neo’s non-drive side for disc brakes and without. 

    With the spacer installed, the brake caliper does not touch the Neo, but the rear stays of the frame are a few mm wider than with the wheel installed as on the road. This one mm causes chain rattle, especially with the smaller sprockets and on the smallest sprocket, the crank hits the chain on every stroke. Clearly that’s not good.

    Without the spacer, all works fine (no noise or cranks hitting the chain) but the brake caliper sits against the Neo housing. It seems fine so far, though with sprints I might rub quite a bit.

    Measuring the wheel vs the Neo: the axle of my wheel is 143.0mm. The Neo without spacer is 142.0mm. The spacer for the disc brake adds 2.7mm on the non-drive side, but the frame seems to “distribute” some of that space into a changed alignment of the derailleur as well. Ideally, for my bike, a 1mm spacer might just work.

    My insights from the topic and my measurements: 1. Not all bikes are equal despite having a standard axle size and 2. Just a few mm difference in a place where it should not matter, actually makes a big difference.