Cycling UK Forum

My bike is a Specialized TriCross Comp which was delivered with the following set up:
Shimano Ultegra rear derailleur,
Roval Pavé Hub
SRAM OG-1070 10 speed Cassette:
Shimano C-5600 chain

From day one I was disappointed with the chainset being annoyingly noisy. It didn’t take much detective work to discover that the source of the noise was the missing teeth which is a feature of the SRAM cassette. When using the 4 bigger rings, which don’t have missing teeth the chainset was silent, but as soon as I go to the 5th ring or smaller, I get a clicking noise as the chain passes the missing tooth.

I eventually got fed up and decided to replace the cassette with a Simano Ultegra 10 speed. This immediately solved the noise problem.

However, I’ve now noticed that the Ultegra Cassette is ‘digging’ into the freehub. The cutouts in the cassette obviously match the raised steps in the free hub, but the raised steps don’t appear to be high enough to adequately hold the rings, allowing them to rotate slightly and dig into the free hub.


Are SRAM and Shimano cassettes supposed to be compatible? Has anyone else come across this problem?

I'm using an SRAM 10 speed cassette on a Shimano Ultegra hub, SRAM 10 chain. No problems at all. - and it isn't noisy either. I suspect your original culprit may have been the Shimano chain.

Out of desperation I've just ordered an SRAM chain today to see if it sorts the problem with the SRAM Cassette. You would have though the tolerance of all the chains was pretty close, but I'll try anything once.

The fault is with the Roval Pave hub. It has an alloy outer body on the frewheel, without the greater height of spline that Shimano engineers reckon is necessary for this weaker (than steel) material to carry the torque you can exert on a sprocket.

When Shimano introduced 10-speed and at the same time wanted to make hubs with alloy bodies, they gave the new 10-speed cassettes deeper slots (than 9-speed cassetes already had) so they could put those taller splines on their new alloy bodies.

There's one limitation: those alloy bodies will take ONLY 10-speed. Other (weight weeny) manufacturers prefer to make alloy hubs that'll also take 9-speed (even 8-speed). So they have shallow splines exactly like Shimano's steel freehubs (that'll take 8, 9 or 10-speed).

You've just proved that Shimano's engineers were right. The Sram cassette would likely have dug into the hub in the same way if you'd left it on there longer.

Thanks Chris.

Your explanation sounds spot on. It’s very disappointing that a £1200 bike should have such a problem.

I’ve tried to upload a photo to show the problem. The biggest three rings are clamped together so I guess they are spreading the load, the problem seem to be the next 3 or 4. These are putting all of the force from a single ring in one spot. This damage has been caused in 500 miles of riding. For a bigger photo see http://picasaweb.google.com/chrisclodes ... 5743054434

I’m grasping at straws here, but do you know if the Shimano freehub fits onto the Roval hub, or would I need to change the whole lot and get the wheel rebuilt.

I may try ringing Specialized tomorrow to see if they will offer a solution, as they did with the dodgy juddering brakes that the bike came with!

Had a set of custom wheels last year which where build with the Hope Pro II hubs (MTB, rather than road wheels) and there was a note saying that cassettes with aluminium spiders should be used on the aluminium free hub. What this does is spread the point of contact between the cog and the free hub so that the pressure at point of contact is no longer sufficient to deform the free hub. This limited the choice to Shimano XTR or a SRAM red 991. Not sure what that translates to in roadie parts.

I 'phoned the Specialised customer support line today, and was told that it was perfectly normal for the casette to dig into the alloy hub body.

Am I being fobbed off?