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skreaminquadz
06-17-2010, 06:31 AM
I apologize for what I expect to be a longish post but thanks for reading it.

I am planning on doing a 9 day tour in the Rockies in late August. The gearing on my Surly Cross Check is not going to work on a loaded touring bike in the Rockies. I currently have a 50/34 compact with a 12-27 cassette - all Shimano. I got wind of SRAM's new APEX line that provides a 11-32 cassette which would probably do the trick for me. So, my question is how much of my newish Surly Cross Check build will I have to change out to use this new cassette. I know I'll need a new rear derailleur and chain. But what about the Shimano shifters, will I be able to use a SRAM rear derailleur with Shimano STI shifters or will I also need to buy SRAM shifters?

Dirt
06-17-2010, 01:30 PM
Hey SQ.

With a longer cage Shimano derailleur and the Apex 11-32 cassette you should be fine.

Here's the scoop: SRAM shifters are designed to work with SRAM derailleurs. They use a different amount of cable pull to achieve the same amount of movement of the rear derailleur. I use many different cogs on my 10-speed wheelsets. My shifters and derailleurs are SRAM Red, but I use Red, Ultegra and Dura Ace cogs (2-different generations). They all shift quite nicely.

With my older Dura Ace bike, I use the same wheels and cogs.

Just gotta make sure that your derailleur can take up the chain length.

skreaminquadz
06-18-2010, 06:52 AM
Thanks Dirt!

So it looks like my plan of keeping my Ultegra shifters to use on a SRAM Apex rear derailleur & cassette will not work. Darn! I was trying to avoid buying those shifters b/c those buggers are expensive. I was even looking at swapping out my rear derailleur for a shimano MTB derailleur, but then I have the 9-speed to 10-speed issue going on.

Gracias amigo!

Dirt
06-18-2010, 07:58 AM
Shimano makes an Ultegra long cage, 10-speed derailleur.

skreaminquadz
06-18-2010, 11:37 AM
Thanks Dirt.

I checked it out and it appears the long cage (GS) can only take up to a 28 tooth cog, if I'm reading it correctly. But I'm probably not becasue it shows both the long and short only taking 28, which doesn't sound right to me. If they both handle the same capacity, then what's the difference?

http://bike.shimano.com/publish/content/global_cycle/en/us/index/products/road/ultegra_6700/product.-code-RD-6700-GS.-type-.html

Mark Blacknell
06-18-2010, 01:20 PM
I can't think of any reason a Shimano MTB rear derailleur wouldn't work in this application. Can you, Dirt?

Dirt
06-18-2010, 02:13 PM
My only hesitancy with a 9-speed MTB derailleur is that the jockey pulleys might be too wide to really mesh well with the 10 speed chain. Those things are soooo dang narrow. I haven't tried it though.

Weird that Shimano puts a 28t max on the Ultegra long cage. My guess is that they wanted to keep the geometry of the derailleur close to the cogs, yet have the long cage able to take up the slack of the granny gear. Since they don't make a 10s cog set bigger than 28, I guess they didn't figrure anyone would use it.

I won't talk about the 2 seasons that I raced my mountain bike in the early 1990s running a DuraAce short cage rear derailleur and a 30t cog. ;)

skreaminquadz
06-18-2010, 03:11 PM
I won't talk about the 2 seasons that I raced my mountain bike in the early 1990s running a DuraAce short cage rear derailleur and a 30t cog. ;)

WHAT!!! But the manual says.... ; )

Yeah, I've been researching the heck out of it over the past few hours and I actually have read a few posts on another forum where people are running Ultegra and DA rear derailleur’s with a 30t cog. So I may be pushing it with a 32, but it's worth a shot before forking over at least $300 for a SRAM shifter.

Thanks guys - you're help is much appreciated.

invisiblehand
06-18-2010, 03:38 PM
Weird that Shimano puts a 28t max on the Ultegra long cage. My guess is that they wanted to keep the geometry of the derailleur close to the cogs, yet have the long cage able to take up the slack of the granny gear. Since they don't make a 10s cog set bigger than 28, I guess they didn't figrure anyone would use it.

That is correct. The difference between a GS road derailer and a GS MTB derailer is the path of the jockey pulley. The tension pulley is the same length -- at least it appears so when eyeballing it. Switching from a short cage (SS) to a long cage (GS) road derailer should have no effect on whether the modification will work. Getting a long cage rear derailer, however, will let one shift to all gear combinations whereas you will probably lose the big-big and small-small combinations (or more) with the SS derailer.

Whether one can mate a 32-tooth cog with a road derailer depends on the length of the derailer hanger. Consequently, one cannot give a global answer without actually trying it. That said, I have never failed fitting a 30t cog with any Shimano road derailer with a little adjustment of the b-screw. Below is my 12-32 10-speed cassette with an Ultegra GS derailer.

http://www.facebook.com/p.php?i=1000567210&k=Z6E33XPYT5TF6BD1P133XSQ2P4IB4ZYL4WFXC&oid=1405148581579

If you are going to pick up a rear derailer, I would try the MTB rear derailer first. Tandem folks appear to use the MTB derailers with 10-speed chains without an issue. Typically you can find an older LX derailers for a reasonable price. Note that Shimano is supposedly releasing a 12-36 cassette that is backwards compatible with their MTB derailers. (At least that is what I recall reading) I think SRAM is doing the same; but it is in the XX line which is wildly expensive.

snefrisk
07-31-2010, 10:56 AM
Hi:)

I just discovered the SRAM cassette my self and I was searching around the internet and came over this thread. I have shimano ultegra and I want use the same cassette. What did you do?

Thanks:)


I apologize for what I expect to be a longish post but thanks for reading it.

I am planning on doing a 9 day tour in the Rockies in late August. The gearing on my Surly Cross Check is not going to work on a loaded touring bike in the Rockies. I currently have a 50/34 compact with a 12-27 cassette - all Shimano. I got wind of SRAM's new APEX line that provides a 11-32 cassette which would probably do the trick for me. So, my question is how much of my newish Surly Cross Check build will I have to change out to use this new cassette. I know I'll need a new rear derailleur and chain. But what about the Shimano shifters, will I be able to use a SRAM rear derailleur with Shimano STI shifters or will I also need to buy SRAM shifters?

skreaminquadz
08-01-2010, 10:20 AM
Well - not much has progressed since my inital post. I was planning on making this change to a touring bike I have for a tour I had planned for late August. Well, the tour was cancelled so I put off this change for now. But I still plan on taking on the upgrade... at some point in the future.

If you find a good solution that worked for you - please update us!! Good luck!

CCrew
12-27-2010, 11:05 AM
Not to resurrect an old thread, but found this googling and figured I'd throw in some technical info for the next person.

The reason that Shimano only specs a 28 tooth max on the rear is because at the time that was the biggest they make. Ultegra will happily go to 30, although beyond that is hit or miss.

LX, SLX, XT, or XTR will all work to 36tooth with the difference being the sweep of the derailer. The jockey wheels will work just fine, and the in/out travel is controlled by the limits anyway. Key is to match the cassette spacing, and as someone's said, the Apex RD will pull differently than Shimano so the RD isn't compatible. The 10 speed spacing however is the same between Apex and Shimano 10 speed cassettes - so as long as you run the cassette with a Shimano MTB rear derailer you should be golden.

Depending on your crankset you'll need to go either mid-cage or long cage RD. I run a compact double front and a 11-32 Apex on the rear with an XT derailer on the rear and a 105 on the front - with ST-5700 105 brifters with no issues. I switch to 12-27 for around town. I can go with a mid-cage, but a lot of tourers are running mountain triples in which case you'll need long cage RD.

Hope that helps someone.

skreaminquadz
12-29-2010, 10:28 AM
THanks CCrew. I ended up buying the Apex group as my c-mas gift to myself. I'm still waiting on shifters but once that gets here I'll be building it up.

Also - welcome to the forum. Long time since we've talked. I'm still riding in to Courthouse - although not as early as you ; )

CCrew
01-04-2011, 06:08 PM
THanks CCrew. I ended up buying the Apex group as my c-mas gift to myself. I'm still waiting on shifters but once that gets here I'll be building it up.

Also - welcome to the forum. Long time since we've talked. I'm still riding in to Courthouse - although not as early as you ; )

Jimmy?

Yeah, I don't ride into Courthouse anymore unfortunately. I get to tough it out across the Key bridge and down M Street now :(

skreaminquadz
01-05-2011, 08:39 AM
Jimmy?

Yeah, I don't ride into Courthouse anymore unfortunately. I get to tough it out across the Key bridge and down M Street now :(

Yes sir!

I see you've found a commute that works for you going into DC that appeases the family as well – that’s always good ; ) So you're ridiculously long 20+ miles into Courthouse is now close to 30 each way into DC I'm sure. You're a beast my friend.

CCrew
01-20-2011, 06:08 PM
How's that 32 working out for you?

I had a 12-27 on the Salsa because that's all I had when I built it, but got a 11-34 here today. Other than the OMG I think when looking at it when I'm so used to road cassettes, Haven't had a chance to ride it until I pick up a longer chain.

I was looking for an almost MTB granny low for loaded touring pulling the trailer, definitely looks like it'll do that, but wondered how the day-to-day was working out on yours.

Thanks!
R

skreaminquadz
01-20-2011, 09:32 PM
How's that 32 working out for you?
Hey CCrew - I'm enjoying the 32 so far. I can definitely notice the difference coming from a 27.

Yeah, I think a 32 would be enough for most loaded touring. I'm also running a compact up front. I'm hoping to get some touring miles on it this year.

I agree, the cassette initially looked ridiculously large, but I'm getting used to it.

CCrew
01-21-2011, 08:36 AM
Hey CCrew - I'm enjoying the 32 so far. I can definitely notice the difference coming from a 27.

Thanks! Yeah, I'm also 50/34 compact on the front. My thought on the 34 instead of the 32 is that I would have the 32 available without fully cross-chaining it.. then if I couldn't get my old legs moving I still had the 34 in reserve. Glad I went to an XT long cage RD, because a mid-cage RD definitely wouldn't have had enough take-up.

I'm thinking running unloaded I'll rarely make it out of the big ring in the front but thinking and doing are usually separate. I'm planning pulling the 38's off of it and going 42-45mm on the tires, in which case the gearing may be perfect. It was bought for C&O type touring so it won't break my heart if it's a spin machine on pavement.

Thanks!
R