Which front deralier?

[thecaptn]

Hi All,

I'm putting together the components for my Surly ECR and am trying to work out which front deralier would suit. The specs as described on Surly's website show a Shimano deralier mounted on a 28.6 band adaptor and so I'm assuming that I'll need to do something similar mountingwise. I'm using a SRAM X9 36-22 crankset and have noticed that deraliers seem to be matched to the large chainring size so once again I'm assuming that I'll need a deralier to suit 36t. Then there's hi and low mount deraliers and hi, low and dual pull deraliers, then there's spec 1,2 and 3 deraliers which seems to relate to the distance that the deralier sits in relation to the seat tube. This is where I start to get confused, I get the difference between hi and low pull deraliers but am unsure about which way to run the cable on this frame, I'm not sure about a hi or low mount or even if it matters and as for the spec1,2 or 3 I've no idea at all.

Has anyone experience with setting up an ECR or something similar? I'd really appreciate any advice to help me work this out.

Thanks in advance,
Pete

[Duck!]

That's a bit daft of Surly to use a direct-mount derailleur with a clamp-on adaptor when they could easily use a conventional high-clamp unit, most of which can be shimmed down to 28.6mm.

Looking at the (rather poor) pic on the Surly site, it appears to be top-routed cabling, so you want either a top-pull or dual-pull derailleur (dual-pull have the cable anchor on a cam-type arrangement that allows the cable to be fed in from either top or bottom, top-pull will only accept the cable from above, and bottom- pull will only work with the cable routed from below).

[RonK]

This is the same setup as used by Salsa too.
I don't know about the ECR frame, but the Salsa Fargo and the Muru copy I'm looking at have no cable stops so a top pull derailleur is required.

[thecaptn]

Thanks Ron and Duck,

I took another look at the frame and can see what you mean as they've made accomodation for a cable mounting on the seat tube.

One of these should work:

http://www.this link is broken.au/sram-x9-10-spe ... erailleur/" onclick="window.open(this.href);return false;

Either Low Clamp Top Pull 31.8/34.9mm or High Clamp Dual Pull 31.8mm?

I can then either use a 28.6mm adaptor or just shim the 31.8mm clamp?

In order to roughly align the ring gears and deralier would I attach the deralier first and then use the BB to put the crank in about the right space?

Sorry if these are stupid questions but I've never set up a crankset or deralier before. I really appreciate the help though....

[RonK]

When I look at the compatibility chart on the Sram site, I see that only the X0 and X7 front derailleur is compatible with a 36/22 crankset.
The Fargo uses the X7 HDM (high direct mount) and uses a Problem Solvers direct mount clamp.

I think you need to install the crankset and derailleur, adjust the derailleur height and alignment, and adjust the high and low stop screws. Then attach the cable.

[thecaptn]

When I look at the compatibility chart on the Sram site, I see that only the X0 and X7 front derailleur is compatible with a 36/22 crankset.
The Fargo uses the X7 HDM (high direct mount) and uses a Problem Solvers direct mount clamp.

I think you need to install the crankset and derailleur, adjust the derailleur height and alignment, and adjust the high and low stop screws. Then attach the cable.

Thanks Ron,

This I can do, you've made this much simpler for me and saved me from buying an inappropriate mech. Much appreciated.

I'll check out the SRAM compatibility chart, it sounds like an invaluable tool.

Thanks again,
Pete

[thecaptn]

Yep SRAM compatibility chart is gold, I had a medium cage rear deralier in my shopping cart but I see that they recomend a long cage for my setup.

[Duck!]

In order to roughly align the ring gears and deralier would I attach the deralier first and then use the BB to put the crank in about the right space?

I would fit the crank then the derailleur.

[thecaptn]

In order to roughly align the ring gears and deralier would I attach the deralier first and then use the BB to put the crank in about the right space?

I would fit the crank then the derailleur.

Thanks Duck, makes sense. I'll do it this way.
Pete

[thecaptn]

I tried fitting up the 30mm Problemsolvers deralier adaptor today and found that the seat tube is actually32.2mm and so it wont fit. I tried mucking around with it to see if I could stretch it but 2.2mm is a fair bit to make up. Now I'm thinking I've got a front deralier which wont work with any other adaptor.

Any ideas for how I can sort this out?

Pete

[Duck!]

Is there enough meat in the clamp to attack it with a file?

[thecaptn]

Is there enough meat in the clamp to attack it with a file?

Yes I've played around with it and I think it will work now, I just need a longer bolt to conect it. i punched the pin out of the hinge and opened up the hole in the arm with a drill, that gave me about 1mm then I used a die grinder and 2" sander to open the clamping face and elongate the bolt hole on the arm to allow the bolt to thread up straight.

[thecaptn]

[thecaptn]

[thecaptn]

The clamp before being butchered.