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My gloves stink
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Discussion Starter #1
Hi gang.

Cassette trouble here. The stock Sram 970 gouges into the freehub body splines. So I bought an XT cassette, thinking that since the cogs are mounted on a spider, the load would be spread out. Trouble is, the spider arms are rubbing on the spokes. This trial-and-error stuff is an expensive way to try to fix things. Anyone out there know what works?
 

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I dig trails!
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5,575 Posts
Appendage said:
This trial-and-error stuff is an expensive way to try to fix things.
Lol. Seems to be your theme for today.

Did a thin ring spacer come with the hub or cassette? I needed one on my Mavic Crossland wheels. The spacer sits on the hub side of the cassette.

The next question is if a spacer will push the cassette too far away for the lock ring to properly engage.

What hub/freehub/wheel are you running?

Mr. P
 

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mtbr platinum member
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1,426 Posts
You should be fine with a thin spacer. I've read that some people had similar issues on their Kings and a Cool-Whip (or whatever) container cut down into a spacer works too.
 

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My gloves stink
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1,486 Posts
Discussion Starter #4
I called WTB...

It's the stock MkIII setup- wtb hub and freehub. I called WTB and they're going to mail me some spacers to put behind the cassette. I'll let you know how it works out.
 

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My gloves stink
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1,486 Posts
Discussion Starter #5
Shimano M760 works fine. M750 doesn't.

Here's the deal. The carrier arms of the CS M-750 sit inboard of the largest cog. That is to say, they stick out between the largest cog and the hub flange. With the WTB hub, there isn't enough room, and the carrier arms rub on the spokes. The carrier arms of the M-760 are outboard of the largest cog, leaving plenty of room for the spokes.

The reason you want to know this is because the stock Sram cassette doesn't use a carrier to support the cogs, so that they gouge into the freehub splines.
 

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baggin ho's
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WTB will send you spacers they aren't specific, you can probably use one of the plastic ones from that POS SRAM cassette you took off. I have an XTR cassette and it doesn't rub with no spacers
 

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My gloves stink
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1,486 Posts
Discussion Starter #7
WTB to the rescue! But I don't need to be rescued!

g-funk said:
WTB will send you spacers they aren't specific, you can probably use one of the plastic ones from that POS SRAM cassette you took off. I have an XTR cassette and it doesn't rub with no spacers
WTB sent me some spacers that arrived the day after I talked to them (I live about 30 miles away from the posh WTB corporate megaplex). Excellent customer support!

One spacer was enough to stop the spokes from contacting the spider, but there wasn't much of a safety margin. Naturally, clearance was better with 2 spacers. But the best solution is to switch to an M760 cassette, which has tons of clearance without affecting chain line.

Summary of thread: WTB hub + M750 = bad. WTB hub + M760 = good.
 

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My gloves stink
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1,486 Posts
Discussion Starter #8
My bad...but it's all good

I was wrong about the spider arms sitting outboard of the largest cog on the 32t M-760. They DO is outboard on the 34t version. They sit inboard on the 32t version. But unlike the inboard arms of the M-750, the M-760 arms don't rub on the spokes. Maybe they're thinner or something. Either way, the bottom line remains the same- M760 cassette works without spacers, M750 needs spacers.
 
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