Mavic Rim - Spacer or no spacer ???

[septuagenarian]

Got some Mavic Crossride rims, basic entry level MTB rims, and they came with a rear spacer.

It will only go on one way and when in place it is very hard to get the cassette lock nut on and it will only lock down about 1 1/2 turns.
The spacer is flat on one side and has three indents on the other side but it will only slip on with the flat side down.

Without the spacer the lockring turns about three revolutions and locks tight although there is a tiny bit of play, but not as much as with the spacer.

My gut feeling is that the spacer is either not required or is not the right type.

[familyguy]

The spacer is usually required for 10s cassettes. Mavic freehubs fit 9s without the spacer, but the 10s were actually narrower and needed the spacer. Not sure about 11s fitments. 1 1/2 turns on the lockring seems ok though.

Jim

[septuagenarian]

The spacer is usually required for 10s cassettes. Mavic freehubs fit 9s without the spacer, but the 10s were actually narrower and needed the spacer. Not sure about 11s fitments. 1 1/2 turns on the lockring seems ok though.

Jim

It's all 9 speed so no spacer should be OK?

[Duck!]

You need the spacer.

Mavic hubs were accidentally road 11-sp. compatible a long time before 11-sp. was even thought of and have a longer freewheel body than normal 8/9/10-sp. hubs. The only time you leave the spacer off is if you're using a road 11-sp. cassette; for everything else leave it on. Additionally, if you use a Shimano Dura-Ace, Ultegra or 105 10-sp. cassette, you also need the thinner spacer supplied with the cassette.

[familyguy]

^What Duck says. I've got the two spacers on for the 10s I run on my Cosmos wheels.

[RobertL]

You need the spacer.
Additionally, if you use a Shimano Dura-Ace, Ultegra or 105 10-sp. cassette, you also need the thinner spacer supplied with the cassette.

I knew that, and yet when I swapped a Tiagra cassette out for an Ultegra, do you think I remembered it? Nooooo, I did not!

Luckily I took my bike for a short shakedown ride, but it took me about 10km to work out where the rattling sound was coming from.

[septuagenarian]

The above is from the Mavic wheel manual and if I'm reading it correctly the box on the left, 06 A, would appear to refer to road bikes and the RH box, 06 B, would seem to refer to off-road bikes.

Just to be clear on my use of the wheels, they are 26" Mavic Crossride MTB wheels and they are going on a 2011 Trek 8000 XC hardtail frame that fell in my lap when I was looking for the final bits for the Trek 6700 rebuild.

What is concerning me is that with, or without the spacer, there seems to be some play in the cassette.

[Ivanerrol]

Had a similar problem last Sunday with a DT Swiss Axis 4 rim and a HG500 10 speed cassette
Not using the spacer caused the derailleur to brush the wheel spokes on the largest cog.
Using the spacer - the lock ring would not tighten up sufficiently.

The problem was solved by using an Ultegra lock ring - it has more threads than the HG500 lock ring.

(Thanks to the boys at De Vers in Alphington)

[septuagenarian]

Bit more info:

The cassette wasn't a cheapie, it's a CS-HG80-9 11-32T and upon googling it I came up with the following Shimano tech doc.


My cassette being 11-32T is an 'ar' type with a built-in spacer and I'm guessing??? the spacer fitted in the other two groups is in addition to the Mavic spacer.

I'm guessing the spacer is to do with the chain line ????

I'm now totally confused but I'll repeat what I said above that with or without the spacer there is some play in the cassette where it sits on the hub, and that doesn't seem right to me.

[Duck!]

The "ar" code simply identifies the sprocket combination, all 9-sp. cassettes are the same width and on normal hubs do not require spacers. But Mavic, for their own reasons, are not "normal", with most models having a longer than typical freewheel body. Mostly it's due to their hub designs often having straight-pull spokes with large flange lobes and needing to make the cassette clear the lobes, and partially it's due to some hubs sharing parts with road models, which also need to accommodate Campagnolo cassettes, which are wider than Shimano counterparts. Therefore some hubs will require a spacer, which is supplied.

The key bit in the images posted above is the right side of the Mavic diagram: note there are two different freewheel body lengths; the longer one requires the spacer, the shorter one shouldn't..... Measure what you have according to the diagram, and make sure the locknut is done up properly tight.