Originally Posted by
nomadmax
I did an internal and external search for info regarding the IRD Sub-Compact 30/46 crankset. Specifically, I'm looking to hear reviews re the quality or any "gotchas" that may have popped up after you installed it. I have two freewheel, 126mm, friction shift bikes left in the fleet; I'm looking at the IRD to get the gearing down to something manageable for the hills and the numbers seem like they'll be perfect.
From my research I know they're JIS and the recommended BB spindle length is 118mm; that seems a little long, maybe even triple territory? The bikes are an 86 Spec Allez SE and an 84 Guerciotti SL. I'm kinda stuck on the IRD for the way they look and that they come in 172.5mm unlike the Velo Orange.
So I guess my questions are:
Anybody using the IRD and how do you like it?
Was a 118mm BB spindle indeed what was needed?
Thanks
I'm not using one, but kudos on them for choosing a smaller BCD that makes a 46/30 easy. There are some pretty ridiculous contortions going on in the "gravel" world to get rings smaller than 34T onto 110mm BCD cranks.
118mm is what my old Sugino GT needs to be set up as a compact double, so it sounds right to me. Older-style cranks with straight arms tend to need longer BBs than modern ones with the arms curving inward to meet the BB spindle.