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Discussion Starter #1
Just out of curiousity,
1. what's the smallest chainring (big & small) you can put on these cranksets?
2. what's the largest cassette you can put on the short cage RD?

Thanks!
 

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arctic hawk said:
Just out of curiousity,
1. what's the smallest chainring (big & small) you can put on these cranksets?
2. what's the largest cassette you can put on the short cage RD?

Thanks!
I'm going to go with the assumption you're talking about the DA/Ult 10 double chainring version (not triple). The bolt circle diameter is 130mm, so the smallest ring big and/or small is 38 teeth. The BCD is the same for the large and small rings.

Your question about the largest cassette (cog) would depend on the RD (and your frame to a certain extent). Assuming (again) that you are talking about a Shimano road RD (DA,Ult,etc) they are compatible with up to a 27 tooth rear cog. The length of the rear derailleur hanger can vary from frame to frame, changing the positioning of the RD relative to the cassette. A slightly longer hanger will place the RD a little farther away form the big cog and a slightly shorter hanger will place the RD a little closer to the cog. So the "general" answer is a 27 tooth cog but you *might* be able to get away with a slightly larger cog (depending).

Check eBay, you might be able to find one of the older short cage XTR RDs that pop up. That's another good option if you want a short cage RD that will work with a little larger rear cog.
 

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Dura Ace/Ultegra 10

I believe you will find it simillar to 9 speed shimano.

1. smallest chainring 38 (true for any 130 crank) although I remember hearing of a company that custom manufactures a 37 that will fit (below this the chainring becomes smaller than the bolt circle. Compact cranks (including the new shimano one) will take a much smaller chainring (at least down to a 34).

2. You can run up to a 27 on the back (per Shimano) with the short cage rear derailer, although I suspect (like with the 9 speed) you may be able to cheat on this somewhat (eg I once ran a 30 on the rear with a single ring up front without any real problems, but it was tight, top pulley almost touched 30 tooth cog).

I have been flirting with the idea of 10 sp. on my cross bike, I don't really need it, but I could look more like the Euro studs.

jhr
 

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38 chainring is smallest.

27 is the biggest in back because Shimano doesn't make anything bigger in 10 speed.

Go with a MTB r/d. I'm running a mid-cage XT with 10 speed Ultegra and it works flawlessly.
 

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And how are all your experiences with muddy drivetrains, DA 8 vs 9 vs 10 speed? My gut tells me 10spd is a very bad idea for cross. And does one really need the iny tiny gaps between gears for the riding style cross dictates? Even with a 10spd 12-27 I can only see myself trying to skip geas when I'm really hammering. Back in the days my 12-28 XTR used to ride sooo well...and they're actually still for sale here and there.
 

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Cloxxki said:
And how are all your experiences with muddy drivetrains, DA 8 vs 9 vs 10 speed? My gut tells me 10spd is a very bad idea for cross. And does one really need the iny tiny gaps between gears for the riding style cross dictates? Even with a 10spd 12-27 I can only see myself trying to skip geas when I'm really hammering. Back in the days my 12-28 XTR used to ride sooo well...and they're actually still for sale here and there.
10 speed drivetrains (campy and shimano) are now tried and true for cyclocross. Lots of folks have been using them for the last 2-3 years and after putting a full season on the duraace 10 I can testify that it is not distinguishable from the 9-speed I used in previous years as far as mud performance. The shape of the shifter is much better though, and the shifters are more durable and can take a lot more abuse. I've had many 9 speed shifters just stop working after a single crash, where my 10 speed shifters took 2 good road crashes and many offroad mishaps before finally being destroyed in a hard crash at the liberty cup race in RI.

http://www.cyclingnews.com/photos/2...id=UScrossnats0515/121105ecnatcross_liberty_5
 

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Nice pic

wunlap togo said:
http://www.cyclingnews.com/photos/2005/dec05/UScrossnats05/?id=UScrossnats0515/121105ecnatcross_liberty_5[/url]
Yeah that mud would kill about any shifter - don't care if its 7 or 12sp its toast in that soup
(All you ludite bar end shifting grouches will of course now jump on me and preach how you installed your Suntour Index bare ends in the fall of 1984 and have not serviced them yet after 65,000 miles etc etc)
 

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arctic hawk said:
Just out of curiousity,
1. what's the smallest chainring (big & small) you can put on these cranksets?
2. what's the largest cassette you can put on the short cage RD?

Thanks!
The big S is coming out with a compact crank so you can go nice and low if you want. Perhaps it's available already? I got a U-10 group from texascyclesport.com with an FSA compact carbon crank option. Good prices, good customer service, and I love U-10. I wish I had the $$$ to convert my crossers.
 

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dreww said:
Yeah that mud would kill about any shifter - don't care if its 7 or 12sp its toast in that soup
(All you ludite bar end shifting grouches will of course now jump on me and preach how you installed your Suntour Index bare ends in the fall of 1984 and have not serviced them yet after 65,000 miles etc etc)
Actually, the mud didn't do it. The right lever blade snagged on a root or something and was yanked outward, breaking some inner part. It actually still indexes all 9 clicks, but the lever is all cocked out to the side.
 

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Discussion Starter #11
dreww said:
All you ludite bar end shifting grouches will of course now jump on me and preach how you installed your Suntour Index bare ends in the fall of 1984 and have not serviced them yet after 65,000 miles etc etc
Actually since you mentioned it .... :D
 

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Road MTB compatibility???

merckx56 said:
38 chainring is smallest.

27 is the biggest in back because Shimano doesn't make anything bigger in 10 speed.

Go with a MTB r/d. I'm running a mid-cage XT with 10 speed Ultegra and it works flawlessly.
Are you running 9 sp cassette & derailleur with 10 sp shifters?? No problems?
 

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mikebikr said:
Are you running 9 sp cassette & derailleur with 10 sp shifters?? No problems?
Any shimano derailleur will work. 10 speed shifters must have 10 speed cassette and chain.
 

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10 speed MTB cassette???

I want to run 10 sp shifters with a mtb cassette. To the best of my availability you can't get a bigger 10 sp cassette than a 28 and no one makes a 10 sp mtb derailleur. Is that correct?
 

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mikebikr said:
I want to run 10 sp shifters with a mtb cassette. To the best of my availability you can't get a bigger 10 sp cassette than a 28 and no one makes a 10 sp mtb derailleur. Is that correct?
The derailleur does not matter. Any shimano derailleur will work on 10 speed. You are correct, there are not any 10speed cassettes available with a cog greater than 28. Get a triple if you want that kind of ultra low gearing.
 

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mikebikr said:
I want to run 10 sp shifters with a mtb cassette. To the best of my availability you can't get a bigger 10 sp cassette than a 28 and no one makes a 10 sp mtb derailleur. Is that correct?
Okay...

The biggest Shimano 10 speed cassette you can get is 12-27. Miche will be coming out with a 13-29 for Shimano splined freehubs soon. There is no such animal as a 10 speed MTB cassette.

As for derailleurs, you DO NOT need a 10 speed derailleur to run 10 speed. The total overall spacing in the cassette range is the same for 9 and 10 speeds. The actual clicks/cable pull is built into the shifter. The derailleur moves a predescibed total distance.
I am running an XT mid-cage derailleur with 10 speed shifters, chain and cassettes.

If you want a bigger range of gearing and/or lower gearing, you'll need a compact crankset.
 

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merckx56 said:
Okay...

The biggest Shimano 10 speed cassette you can get is 12-27. Miche will be coming out with a 13-29 for Shimano splined freehubs soon. There is no such animal as a 10 speed MTB cassette.

As for derailleurs, you DO NOT need a 10 speed derailleur to run 10 speed. The total overall spacing in the cassette range is the same for 9 and 10 speeds. The actual clicks/cable pull is built into the shifter. The derailleur moves a predescibed total distance.
I am running an XT mid-cage derailleur with 10 speed shifters, chain and cassettes.

If you want a bigger range of gearing and/or lower gearing, you'll need a compact crankset.
Okay, I've been reading this forum for days and searching relentlessly trying to get my $h!t straight before I started spending more cash. It's my first cross and first build.
Just to be double secret probation clear: Ultegra 10 spd shifters + XTR med cage rear + 10 spd cassette + 10 spd chain = good times? The gearing possibilities allowed by such a setup lead me to think I may go compact crank, just for extra climbyness. Maybe with an 11-23 or 12-25. Sound good?
 

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studiddy said:
Okay, I've been reading this forum for days and searching relentlessly trying to get my $h!t straight before I started spending more cash. It's my first cross and first build.
Just to be double secret probation clear: Ultegra 10 spd shifters + XTR med cage rear + 10 spd cassette + 10 spd chain = good times? The gearing possibilities allowed by such a setup lead me to think I may go compact crank, just for extra climbyness. Maybe with an 11-23 or 12-25. Sound good?
That will work no problem. For cross racing you won't need that 11t cog, but otherwise you're all good.
 

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Yeah, I'll probably go 12-23. A friend of mine has been trying to talk me into going 9 speed (and buy his old DA shifters), but from what I've gathered the Ultegra 10 is mounds better than the 9 stuff. I've got U 10 on my road bike and like it well enough. I wish there were a way to get a compact crank into probikekits 'kit builder'. Thanks for the help.
 

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studiddy said:
Yeah, I'll probably go 12-23. A friend of mine has been trying to talk me into going 9 speed (and buy his old DA shifters), but from what I've gathered the Ultegra 10 is mounds better than the 9 stuff. I've got U 10 on my road bike and like it well enough. I wish there were a way to get a compact crank into probikekits 'kit builder'. Thanks for the help.
Might want to look at the cassette thread before deciding to go compact ... 38/46 and 12-25 or 12-27 are the concensus choices for racing. If your prime concern isn't racing or you have other constraints, then by all means go compact.

FYI, texascyclesport.com sells U10 groups with FSA compact carbon cranks for a good price and very good customer service. Went compact on the road bike but wouldn't think of it on the crosser.
 
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