I am building a road bike with disc brakes. I ordered Elite wheels, and an 11 speed cassette. The wheels don't have a wide groove (all grooves are the same size) in the freehub. To my surprise the cassette I purchased fits...it doesn't have a wide spline (all splines are the same size). Is this the standard now? My experience is with freehubs that have a wide groove, and cassettes that have and wide spline.

There is no single standard spline pattern but the one you are familiar with is Shimano Hyperglide (HG)

What cassette did you purchase?
A Shimano or ???

A ZTTO cassette

Well, I know my eyesight is poor but didn't realize it was this poor. After further examination of the freehub, it does have a wide groove. My eyesight didn't fail with the ZTTO cassette though. It doesn't have a wide spline (all splines are the same size).

I will bet (fake) money that you're wrong about the ZTTO cassette. If it fits on the free hub.

If your hub has a wider groove, it is adjacent to a narrower spline on the hub.

The cassette must have a corresponding wider spline adjacent to a narrower groove. This is how loose cassette sprockets are oriented properly.

I happen to have a ZTTO cassette that is fully compatible with a Shimano-standard hub as I describe above

Post a good detailed picture of each and prove me wrong! Here's one I pulled from the web.

Here is a picture of my ZTTO cassette that does not have a wide spline.

Interestingly, the SRAM red cassette has the same spline configuration as my ZTTO cassette....no wide spline.

The single wide spline is there to help clock all the cogs correctly. This feature is only needed when you have loose cogs in your cassette. It is not needed when you have a monobloc cassette.

I stand corrected! Thank you for the update!

Interesting about the monoblock, and if I had a great memory, I would have remembered that. I've only had one monoblock cassette in my life - a Red 10 speed at least 10+ years ago maybe 15. I guess i just didn't remember. Thanks for posting the pic and your patient understanding of my ignorance - or poor memory, take your pick!

Suspect it only needs the long tooth to make sure single cogs fit on the right way and with that monoblock, a uniform 2 narrow splines still fit those two slots.

edit: took me so long to write this, icemilkcoffee beat me to it

Ahh! Thanks for explaining this. In all my years of cycling, this is the first time I've had a monoblock cassette and I never knew this. Just goes to show how important forums like this can be.