I have a couple of fun cranksets and I'm contemplating a few ideas for which I'd love your input.
Crankset 1. Ritchey Logic Compact crankset with 42/32/22 chainrings 94/58 bcd. Crankset 2. Suntour XC Pro crankset with 46/36/24 chainrings power ring 110/74 bcd (I actually bought a few things with this, mtn thumb shifters (7 spd), rear derailleur, rear hub, freewheel - all XC Pro) I'm perfectly content with the Sugino triple 46/36/24 on my Bombadil and I actually have nothing against triples, but I'm contemplating converting one of the cranksets above to a double just because who doesn't need a project to tinker with your Riv? The bike is a do-it-all All Rounder, so I want to have wide gearing range, something like a 42/32 double with a 12-36 cassette would accomplish that for me. A 46/36 might not quite cut it, but I could go low low 36-24 too. Anyway back to converting a triple into a double. As I understand it, there are a few ways to do that: 1) Remove the big chainring (potentially swap it for a chainguard) and call it a day (or change some chainrings) 2) Remove the little chainring and call it a day (or change some chainrings after) But... not so fast. If I go with option 1 without the chain guard do I need new / shorter chainring bolts? If so, which ones do I get? Are these universal? Are the pros/cons of either option? Will I run into Q-factor issues, chainline and chainstay / derailer problems? I had read this on an old post: "my Bomba and I suppose a Hunqa frame you are limited to a 36t middle unless you get a wider BB." So, what about the bottom bracket? Do I need to go narrower to get the right chainline? Or wider to fit the 32? I tracked down a few conversations from way back, here and in other forums. It seems like the original suggested bottom bracket for these cranks are: 1) Ritchey Logic Double - 110-113mm (this is probably close to what's in there now) 2) Suntour XC Pro - Suntour Greaseguard 122.5mm (I managed to get my hands on one of these) For the Ritchey as a double (when removing the inner ring) I heard people suggesting a Phil 98mm BB which I cannot find. Another alternative is using a 103mm with some hacks <http://alexwetmore.org/archives/423.html> For the Suntour, I have no idea what is required in terms of BB. Maybe you just have to try a few. What does the collective knowledge here recommend? Ritchey or Suntour? Remove the outer or the inner? Thanks Max -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/rbw-owners-bunch/d9bf4563-b097-46d5-bbed-718f07a33121n%40googlegroups.com.
