[Closed] Tightening a cassette lockring against one of the bigger sprockets?

Do it up tight.  Check after the first ride.  If ok check every 6hours.

Maybe use a drop of threadlock on the threads?

Ok good, that was my thinking that the only difference was the little locking teeth.

Could actually buy a 16-27 Ultegra cassette and just use the 16 tooth locking sprocket, but couldn't use the remainder of the cassette so would be an expensive option!

The smallest cog normally has a ring of shallow teeth running around the outside face that engages with the lock ring. This is the clicky feet that you get tightening or loosening the lock ring. Bottom right in this photo:

Yep thanks JoeG, that's what Keith and I were talking about, debating the risk of it coming loose.

I've had under tightened lock rings come loose on their serrations.  No harm done,  but I worked out what the clunking noise was!  40Nm is quite tight compared to most bike bolts at c5Nm .

The torque is the main thing that keeps them on .

Does a 16 fit inside the chainstay with the chain on?

Hmm... good point! Will need to check, could pull wheel back in drops to make more space but preferred the idea of slamming the wheel forward.

Are you using a 10 speed mech with the limit screw wound in?

Or is the spacing the same on 7 & 10 and it just got narrower for 11+?

(Just curious/interested).

Actually another potential issue is that the lock ring may tighten down on its threads before tightening the cassette. Lock ring sprockets overhang the end of the freehub body to prevent this. An extra cassette spacer may sort this either by spacing the cassette away from the spokes, or up against the lock ring .

The splines on the freehub don't go to the edge, so it's a bit of a no-go from the start; you will need to add one or two of the small plastic spacers that go between sprockets and tighten against that.
This is the way most singlespeed conversion kits work anyway, so I don't think there is any risk of it getting undone.

Absolute black used to make a lockring specifically for use on bigger cogs, it was just slightly larger and was smooth. Still works properly at normal cassette torque, I think Shimano tend to over engineer things.

I once tried conceptually to build 4 speed but I left 11T smallest cog not to faff with lockring.

Never went pass first try though...

Cheers!
I.

Dremel some grooves on the face of the cog?

I ran single speed for yonks in the 90s with just a bunch of cassette spacers and a single sprocket somewhere in the middle of the carrier. Never came loose.

I did similar with 6 cogs from a 105 cassette on a Hope SS/Trials hub. 15-25. The lock ring tightened up on the 15t cog fine. Just make sure the cog overhangs the edge of the freehub body slightly so the lock ring doesn’t bottom out on the threads first.

I’ve got some photos somewhere. I’ll dig them out.

Single speed kits lock down the same way against the spacers, they don’t have serrations like an 11t cog. You’ll be fine.

Not all lockrings are the same size so you may be out of luck - I had to swap from 11- to a 12- lockring because when I removed the small sprockets from my nephew's TCR the smallest lockring would not engage (he races on a gear restriction so no 11,12,13, sprockets). Don't worry about the serrations. Just do it up tight.

I also have two Surley sprockets on a SS freehub with no issues.

Thanks all

Are you using a 10 speed mech with the limit screw wound in?

Or is the spacing the same on 7 & 10 and it just got narrower for 11+?

(Just curious/interested).

Spacing is narrower for 10 speed than for 7 speed. The advantage of going 10 speed is therefore that I can fit more cogs in! I think Suntour say 5x7 speed cogs or 7x10 speed cogs.

Also 10 speed allows me to run narrow wide and is cheaper (generally) than 11 speed once you take into account availability of bar end shifters etc.

Good points about singlespeed sprockets, I've used enough of these in the past, should have remembered!