I'm upgrading my bike from 8 speed to 10 speed.

The rear hub is a Shimano 8spd cassette compatible Edco.

I have purchased a 10spd Shimano XT cassette. It fits onto the freehub body's splines. With no sprockets the lock-ring can be threaded on 3 full turns.

However when I tighten the lock-ring the sprockets are still a bit loose.

Investigation shows that the smallest sprocket is tight to the free-hub body (as the cutouts that fit the splines do not run all the way through the sprocket). This allows the lock-ring to engage 2 & 1/2 turns.

Fitting a 1mm spacer under the largest sprocket removes the sprocket looseness BUT means the lock-ring only engages 1 & 1/2 turns, probably not enough for durability (did I mention this is a tandem with a combined crew weight of 150kg that likes to stand on the pedals up hill). I'd be happy with 2 & 1/2 turns plus tight sprockets.

The ideal solution would be thinner spacer (I need to measure the lock-ring thread pitch to figure out exactly how thick) but I can't find any.

Any thoughts or other possible solutions.

D

I believe the XT uses an aluminum lockring. You can use a steel lockring from a lower end cassette if you're worried about pulling threads off.

Does the freehub have a notch around the outer end?



The freehub body on the left will take all cassettes, starting at 11T and larger. The feehub body on the right will only take cassettes starting with 12T sprockets.

Confusing!
The Body on the right will only take 12T or larger.

Or a Token lock ring. https://www.amazon.com/Token-Products...token+cassette MUCH better than most Shimano lock ring, and occasionally on sale for ridiculously low prices - I got 3 for $5- ......

New Lock Ring Should have come with the Cassette. ^^ Better ? just because it is Aluminum, not Steel?

Better because is has about double the thread length. My Token lockring engages at least 5 full turns. And it's goooooooollldddd.

Thanks for all the help and tips.

First off to clarify it is an 11T-32T XT cassette. The steel-lock ring from the old 8spd (12T-28T) cassette does not fit the 11T cog so I have to use the new lock-ring or the Token option recommended by Nigel.

Next the splines are not cut down like CliffordK's photo above (left), in fact they seem to be set up to handle both a cassette and a screw on block.



My options would seem to be:
a. discard the spacer and grind the end of the splines off - tricky because they will be hardened and if I take too much off the 11T cog will slip
b. keep the spacer and grind the spacer to down to allow for another 1 to 1&1/2 threads to engage.
c. keep the spacer and use a longer lock-ring such as the Token.

I'll post back with my preferred solution once I have decided.

Ok, when you look at the Sheldon Brown site, there are 3 freehubs:

Shimano Cassettes & Freehubs



The uniglide has all the splines the same width, and does not take a lockring (only a locking sprocket). The Hyperglide/Uniglide compatible has the narrow/wide spline for one of them, and will take either a locking sprocket, or a lockring (which is what you have).

I thought those hyperglide/uniglide hubs were only for 6s and 7s cassettes, so I'm a bit surprised the 10s fits on it.

Is that a Shimano hub? Have you ever taken the freehub off? It is possible you cold replace the freehub with an 8/9/10 freehub.

So, you have few choices:

• Try a cassette with 12T as the smallest sprocket.
• Try to get the perfect back spacers, and hope it holds. You'll also get fewer threads for the lockring. Clearance between the lockring and the dropout may be an issue, although it looks like you should have long enough of an axle sticking out.
• Try to find a replacement 8/9/10 freehub.
• Grind a groove into the freehub to be compatible with 11T sprockets. This may ruin the freehub for using uniglide cassettes, but perhaps it doesn't matter.

It's an Edco (Swiss) hub from the mid 1990s. The freehub body has the wider spline and was fitted with an 8spd Shimano XTR cassette.

Anyway, I've just spent 10 minutes in the workshop with a die grinder and carefully removed 0.5mm from the end of the splines on the freehub body. Now it locks the cogs up tight without the spacer and I get 2 & 1/2 turns on the lock-ring. That's as good as it will get with the current lock-ring.
Just to make sure I have ordered a Token lock-ring to see if there are more threads.

Thanks for your help

Just found this

Shimano Cassettes & Freehubs

I'd agree, I thought freehubs with both of the lockring setups were always 7 speed.

If the 1mm Speer you already have is aluminum, or you're VERY patient, laying a piece of [coarse] sandpaper on a flat surface and moving the part in a figure 8 motion is a decent way to thin it down while keeping the sides parallel enough to work just fine for a cassette.