Cyclocross - SRAM 11-26 Downhill cassette for road/cross bike

What do you think of using SRAM's 11-26 downhill cassette on a cross bike that will be ridden on and off road with a 46/36 crank up front?

http://aebike.com/page.cfm?PageID=30&action=details&sku=FW6158

It's the only cassette that I can find that has a 11-tooth small and something bigger than a 23.

I put the SRAM 11-28 on my road bike with a compact (50/34) crankset. No problems at all. I didn't even have to adjust the dr with the switch (original cassette was Shimano 12-25).
http://aebike.com/page.cfm?PageID=30&action=details&sku=FW6206

So I would not expect you to have any issues with the 11-26 cassette and your CX chainrings. I'm not sure of the difference between SRAM's PG and OG series of cassettes.

I am guessing that the downhill-specific cassette is beefier, and thus heavier.

Shimano Ultegra 9 spd 12-27: 224g
SRAM PG-970 DH: 325 g

How much rotational inertia will this add? It's on the hub, so not as much as adding 100g out on the rim.

You guys are comparing 10 speed and 9 speed cassetted here.

You guys are comparing 10 speed and 9 speed cassetted here.

I saw that and just pretended like it was 9 speed. It really makes no difference with what I am trying to accomplish.

Basically, here's how I see it:

-My road bike has 53/39 chainrings in the front and a 12-25 cassette in the back.
-My cross bike will have 46/36 chainrings in the front.

Below I have come up with the gear inches for a few gear combinations. The first is my current road setup, which is a lightweight aluminum bike. The second is what I would probably run if I was riding a steel road bike. The third and forth are proposals for my cross build. I am running a 700x23c tire.

Gear inches:

Current road
53-12: 116.1
39-25: 41.0

Theoretical steel road:
53-12:116.1
39-27: 38.0

Cross 1:
46-11: 109.9
36-26: 36.4

Cross 2:
46-11: 109.9
36-23: 41.1

You can take 2 cassettes, take them apart, then combine the gears you like for a custom casstte.

You won't be able to do this to cogs mounted to a spider, but maybe take the low gears from a 12-26, and the high gears from a 11-23.

You can take 2 cassettes, take them apart, then combine the gears you like for a custom casstte.

You won't be able to do this to cogs mounted to a spider, but maybe take the low gears from a 12-26, and the high gears from a 11-23.

Have you tried this with cross-brand cassettes?

Assuming this is for actual cross racing, I'm betting a 46 x 12 will as much or more than you'll ever need.

Assuming this is for actual cross racing, I'm betting a 46 x 12 will as much or more than you'll ever need.

As I said, it will be for both on and off road.

You guys are comparing 10 speed and 9 speed cassetted here.


I saw that and just pretended like it was 9 speed. It really makes no difference with what I am trying to accomplish.

Yep. I was only comparing the two outside cogs....the cogs in the middle don't make as much of a difference as to whether the cassette will work with the change rings.

Why not an 11/32 mtb cassette?

Why not an 11/32 mtb cassette?

I don't want a big difference between gears, and I don't need a 32t low gear. All I need is a 26 or 25.

http://aebike.com/page.cfm?PageID=30&action=details&sku=FW6177

I use an 11-26 PG-950 for the horrific climbing days on the road bike.

My cross bike is generally set up with a 48-38 crank and an IRD 11-28 cassette. With a 10-tooth difference in front, I'll bet an Ultegra double RD would handle the 11-28 with a little tweaking. However, the XT mid cage allows me to quickly swap to an 11-32 for horsing around on the few easy mountain trails around here.

I agree with wanting an 11-tooth on the road. I think I'd spin a 46-12 gear out a little quickly with road tires on the cross bike. My highest gear on the cyclocross commuter is a 48-11 and it's rare that and run out of gears at the top end.

What do you think of using SRAM's 11-26 downhill cassette on a cross bike that will be ridden on and off road with a 46/36 crank up front?

http://aebike.com/page.cfm?PageID=30&action=details&sku=FW6158

It's the only cassette that I can find that has a 11-tooth small and something bigger than a 23.

No, Sram makes a regular nine speed, 11-26 road cassette, as mentioned above, called the PG-950. Get that one, not the Sram PG-970 11-26 Down Hill cassette.

shimano HG50 9speed 11-25 is also an option if you don't want the 26: http://www.nashbar.com/profile.cfm?sku=22374

I got one for a set of road wheels on my cross bike for $21 after all discounts last month, dunno how well you could do now. I'm riding on road mostly though, with a 50-36. Didn't need to do any derailleur adjustment, it just worked.

No, Sram makes a regular nine speed, 11-26 road cassette, as mentioned above, called the PG-950. Get that one, not the Sram PG-970 11-26 Down Hill cassette.

Sweet. thanks for pointing me out to that? How is the quality on the 970 series? I want something that isn't going to wear quickly and shifts well.

Sweet. thanks for pointing me out to that? How is the quality on the 970 series? I want something that isn't going to wear quickly and shifts well.

I believe the Sram PG-950 is at least Shimano 105 quality or better. It weighs around 234 grams or so versus 325 grams for the 970 downhill version. The 970 DH cassette is not a normal 970 series. 970 series are usually lighter than 950 series, like Ultegra versus 105 series. Since this 970 DH version is built a lot heavier, perhaps you can expect to get significantly more life out of it than the 950; I don't know for certain. I believe both would shift very well.