nickw

I have a really nice NOS HG70 7 speed cassette I am trying to put on a 10 speed shimano XT hub. Looks like a 4mm spacer gives me the proper spacing. Issue I am running into is that the hub has (3) rivets behind the large cog that seat up against the spacers, they poke out maybe .5mm. Due to this, no matter how tight I get the cassette, it has very slight play, rocking back and forth since the the cassette is basically sitting on the those (3) rivets and not sitting flush on the spacers.

Wouldn't be a problem if using a 7-speed hub as the rivets would be sitting above the cassette flange.

Any thoughts? Pic below:

SkyDog75

I ran into the same issue when using a 9-speed cassette on an 11-speed hub. The fix in my case was to find s spacer with notches for the cassette's rivets. Glancing at Google, it seems that there may be notched 4 mm spacers that'll do the trick for you.

hueyhoolihan

or you can make three little indentations in a spacer yourself. a punch and a hammer might suffice. or a drill...

you might want to check that a four millimeter spacer is enough. if not, the lockring may be bottoming out before reaching the face of the cassette. i say this because i find it hard to understand how what is a essentially a three legged stool can rock, especially since it is being forced into a comparatively soft piece of plastic that should easily deform.

RoadGuy

The three rivets are not spaced equally. Place the spacer on top of the cassette and mark the locations. A hammer and chisel, or screwdriver, or nailset will not provide enough control to accurately cut, or indent the spacer ring. Use a dremel tool with a cutting disc to notch the spacer deep enough to provide clearance (about 1/2 the thickness of the spacer) for the rivet heads.

Mark the spacer so you will know how to line it up when assembling it to the freehub so the notches will line back up with the cassette when you install it.

dabac

+1

Last time I did that assembly, I needed both a 4 mm and an 1 mm spacer to get the fit right.

dsbrantjr

I just grind the rivets flush. They are there to keep the cogs together before assembly. Once the cassette has been mounted to the freehub they serve no purpose. There are notched spacers, which were mentioned in an earlier thread, available but I do not see the need for them. If you want to leave them and they are uneven, a few quick strokes with a file should even them up sufficiently.

ThermionicScott 

Just grind divots into the spacer, then you don't have to mess with a stack of loose cogs whenever you service the wheel.

HillRider

The rivets, or often small diameter bolts, are there to just make assembly easier and they provide no needed structural support, particularly if used on a steel or Ti freehub body. You can remove them by grinding off the heads or unscrewing them using a 1.5 mm (IIRC) hex key.

Another method is to put the spacer on after the entire cassette is installed and under the lockring. That works and bypasses the rivet/bolt interference. Done either way you will have to readjust the rear derailleurs limit screws.

BTW, the standard spacer is 4.5 mm.

ThermionicScott 

If installed last, the spacer would need to have the fine teeth to engage the lockring -- do they usually?

FWIW, I favor grinding rivet clearance into the spacer because it's a one-time thing. If you remove or grind off the rivets on the cassette, you'll need to do that again for each new cassette.

HillRider

No, the spacers don't have the teeth but they don't need them. If the lockring is torqued to the recommended 40 N-m or so I've never had one come loose.

ThermionicScott 

That's good to know. I've always played it safe since I don't use a torque wrench to install the lockring -- I probably should.

nfmisso

One the Shimano 7 speed 13-26 cassette I have, it was held together with three hex bolts, which required a 3mm socket (or similar) to remove. On other cassettes it has been 1.5mm hex key bolts or rivets. My moto-tool make short work of the rivets. All my freehubs are steel.

I have also put the spacer ring on the outside - no issues - yes I use a torque wrench. They are $10- at Harbor Freight so no excuse for not having one.

If you don't have a torque wrench, measure the length of your wrench in inches, divide by 12 to get feet. 40 n-m is ~30 ft-lbs. So if you have a 1ft long wrench on the lock ring tool, you need to exert 30 lbs on the wrench. If you have an 8 inch long wrench, you'll need to exert 45 lbs of force. You can calibrate your force with the weight of your bike.

ThermionicScott 

I've got a torque wrench and use it for most fasteners, it just seemed awkward to use on cassette lockrings, and I've never had one come loose. I need to check if I have a 1" socket at home...

The rivets on the HG50 cassettes don't seem to protrude as much as the bolt heads on HG70 and up cassettes, so there's that. I bet HG20 cassettes wouldn't need any of this, since the largest cogs piggyback on smaller ones rather than being attached with shared rivets. Haven't tried those ones as I don't use 12-28T or 12-32T.

FastJake

I grind the rivets down and punch them out so I can do a better job cleaning. I'm slightly OCD...

Sometimes it is necessary to cut up a cassette when making a custom cassette or picking out a desired cog.

miamijim

+1 but without the OCD.

grind'm off and punch'm out

SimonSan

Totally agree... the rivets serve no purpose unless you want to display your cassette to the crowds

fietsbob

though on a light alloy cassette driver each cog spline will make a gouge mark as it transfers the force to get you up Hills

HillRider

+1 Which is why I mentioned the bolts aren't needed if you have a steel or Ti freehub body. Shimano uses steel on all but Dura Ace which has a Ti body. Their sole exception was the 10-speed only 7800 hubs and those weren't in production long and certainly aren't an issue for the OP.

FastJake

The problem is cheap knockoff hubs that use aluminum bodies with the regular spline pattern to save weight. Cogs will cut into those bodies. The DA7800 aluminum body used taller splines to avoid this issue.