Front Shifting on Silvio 1.5

[castlerobber]

I just got my Silvio 1.5 back from being built up at the LBS. The mechanic told me that they could only get the front shifting to be "acceptable" instead of "very good," By "acceptable," he apparently meant "will shift from small to large ring only when the chain is on one of the two smallest cogs." I didn't find this out until I got home, as it was pouring rain when I picked up the bike.

I have the SRAM Force 22 front derailleur, SRAM Apex compact crankset with 165mm cranks, SRAM X7 medium-cage rear derailleur, SRAM PG-1070 12-36 10-speed cassette. I swapped the 50-34 round rings that came with the crankset for 46-34 Rotor Q-rings. The mechanic says he can't get the derailleur close enough to the chainrings with that setup, and that it's even harder to set up with those elliptical rings, so if I want it to shift well I should just go back to the 50T round ring.

Did I pick incompatible parts, or is there a trick to setting up the front derailleur that I need to share with the mechanic?

 

[ratz]

The Force 22 is a road derailleur and you have MTB sized from rings; so the mounting reach isn't low enough. The Force 22 will "just" fit a 50T Q-ring and works better with a 52.

If you want to use those rings you will likely need to a X9 Front Derailleur; it has a model that is "High Direct" mount designed for a bike that has the derailleur braze-on a long way from the crank. This will give you more reach to get the Derailleur lower. The X9 is the only SRAM model that has a High, and Low mount in both direct (braze-on) and clamp on. So it would be the only one that might work.

Alternatively; Steve here on the forums makes a braze on replacement for the Silvio and Vendetta stems. It's arguably better than the stock setup. You cut off the end of your stem to remove the braze bracket and then install his. His has more reach downward; and then you could use the Force 22. It's just a matter of if you are comfortable cutting the frame.

Order of quality of solutions

1) Steve's Bracket replacement
2) X9 derailleur
3) 50T round ring.

 

[castlerobber]

The specs on the X9 derailleur claim it only fits up to a 42T outer ring. I won't say I'm "comfortable" cutting the frame, but that sounds like the best overall solution. Now to figure out how to contact Steve on this new forum...

 

[Charles.Plager]

. Now to figure out how to contact Steve on this new forum...

Find his user on the member's page, click on the Information tab, and then Start a conversation.

Easy-peasy.

 

[castlerobber]

Find his user on the member's page, click on the Information tab, and then Start a conversation.

Done. Thanks!

 

[ratz]

The specs on the X9 derailleur claim it only fits up to a 42T outer ring.

The capacity difference will matter more than the max stated size as the size assumes it's on a standard frame MTB frame. It can do 42/28 which is a 14T delta; your 42/36 is 12T delta give or take 2T for the q-ring affect. You'll just be installing it "offset" with the high-offset version. The question is will your LBS have one you could just try or would they be willing to bring one in for you to try.

Steve is here: http://cruzbike.com/forum/members/scabinetguy.3360/

 

[castlerobber]

The question is will your LBS have one you could just try or would they be willing to bring one in for you to try.

I can ask them. They do carry a lot of mountain bikes, so they might have one on hand. Another option would be to see if I could exchange the 46T Q-ring for a 50T Q-ring. I wasn't sure if I could handle that big a gear--I never used the 52T round ring on my road bike triple, staying almost exclusively on the 42T Q-ring--or I would have gotten the 50T to start with.

 

[ratz]

I can ask them. They do carry a lot of mountain bikes, so they might have one on hand. Another option would be to see if I could exchange the 46T Q-ring for a 50T Q-ring. I wasn't sure if I could handle that big a gear--I never used the 52T round ring on my road bike triple, staying almost exclusively on the 42T Q-ring--or I would have gotten the 50T to start with.

Went through that too. Form Mrs Ratz the 50T round is big. the 52T Q-ring is actually easier by her estimation. She's running 52T/34T on her Q-rings.