Is the second cassette needed for OTK 401 RR?

I run KA100, and the second cassette on the engine side of the axle doesn’t seem to have any purpose. I’ve seen KA100s ran with only 2 axle bearings but mine is currently using 3. Is it okay to remove the unused one?

Yes. Usually, you’d want to undo the screws and tie the 3rd with zipties so it’s floating. Should you need more stiffness in the rear, you can put the bolts and grub screws back on tight and see how it feels. Gives you one more tuning option and very low effort instead of changing an entire axle. Generally, I don’t think people use that option frequently on the single speeds, but I may be mistaken

Yeah it was floating prior, but I was putting the axle back in and i was just like what is the purpose of this bearing. So if i remove it im just losing a tuning option pretty much? or do i need to leave it floating for stability?

If you’re not using it as a tuning tool, then you don’t need it in there. I removed mine for weight savings, but I never found myself running it tight anyway.

I rarely run it but unless you need to pull it for weight savings you might as well keep it in so you have the option of tuning with it if you want.

No set screws and the top two bolts in emulates going one step harder on the axle without changing the axle. It’s not the same but it gives you an idea of if you should change the axle.

If you don’t change axles as a tuning tool though, it’s kind of irrelevant.

It’s a cheap tool in your quiver though worst case.

yeah i am right at the weight limit for running senior class so i think ill remove it just for a little extra weight safety.