On Jul 11, 2:53 pm, R Gonet <richard.go...@earthlink.net> wrote: > Why not just remove the smaller ring and replace the larger one with > the 42T?
Chainline and drivetrain noise would be the issue here. IME, the outer ring on the Quickbeam setup (which is the "middle" ring on a triple) is slightly outboard and the smaller Quickbeam ring slightly inboard "ideal". (And this hasn't been an issue with mine, ever, in either fixed or free setups). Simply swapping the ring would move the front chainline out (guesstimeasuring here) maybe 5-8 mm's, depending on the chainring. That would be a bigger change than I'd be comfortable with on a single chainring/sprocket setup. Now, you could do that if you removed the inner and middle rings and installed a shorter bottom bracket. But, the clearance between the crankset and the chainstay may be too tight to allow this, even with the inner ring and bolts removed. I have not tried this. It's relatively close to start with, and you probably only (no measuring this time) gain 2-4 mm's by dropping the ring and bolts. The simplest thing (in terms of the gearing) would simply be to remove the inner ring and replace the 40T middle ring with a 42 x 110 (or the cool "no cutouts" 44T) http://www.rivbike.com/products/list/cranks_bottom_brackets#product=12-012 But it sounds like Michael was looking for a narrower tread as well, which complicates things a bit further. What I'd probably do is pop the driveside crank and remove the innermost ring. Then I'd reinstall and carefully measure the clearance distance. It might be as simple as a bb with a shorter spindle. If he had 5 mm's or so of of clearance between the frame and the crank, I'd go ahead and see what kind of chainline he'd get with the ring mounted outside. With those cranks, you're probably going from 113 (I didn't check this) to 103, which would make me wary enough to double-measure everything for clearance rather than cinch everything down and find something is hitting the frame. Now....after all that. I did swap my Hilsen crankset for a Ritchey "Cross" Double setup. It feels nicely narrower than the XD-2's. (But the original tread/Q never bugged me). http://www.flickr.com/photos/cyclofiend/3069944090/in/photostream/ Hope that's of some help, - Jim "shellac is drying, now I'm heading back to the bikes...." --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To post to this group, send email to rbw-owners-bunch@googlegroups.com To unsubscribe from this group, send email to rbw-owners-bunch+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en -~----------~----~----~----~------~----~------~--~---
