Which Gear Ratio is Better?
05-23-24, 02:37 PM
#51
Senior Member
I am trying to figure out my gearing as well. I built up a gravel bike with SRAM and currently using 30-43 chainrings and a 11-34 cassette (12s). My only issue is when on the road I sometimes running out of gears on the top end and on the hills I rarely use the small ring. On ANY sort of downhill I ALWAYS run out of gears and end up spinning wildly just to do 35-40 mph. I have a 34-46 crank ordered so hopefully that will be the sweet spot. FWIW most of my other bikes are vintage with much taller gearing but I am getting older and need to make the hills more enjoyable.
05-23-24, 09:49 PM
#52
Newbie
Thread Starter
My best guess would be yes. There are many discussions regarding the 16T cog and the preference for having single tooth caps up to the 17T cog. Mathematically, a two-teeth gap between the 15T and 17T cogs is a much bigger change than a two-teeth change from a 52T chain ring to a 50T chain ring. Why don't you try riding without using the 16T cog and see if you can deal with that?
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05-23-24, 10:26 PM
#53
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Yeah. Think of the 16T cog as the fourth gear in a 6MT; while you could theoretically drive without it, acceleration would not be smooth or fast.
05-23-24, 10:44 PM
#54
I am trying to figure out my gearing as well. I built up a gravel bike with SRAM and currently using 30-43 chainrings and a 11-34 cassette (12s). My only issue is when on the road I sometimes running out of gears on the top end and on the hills I rarely use the small ring. On ANY sort of downhill I ALWAYS run out of gears and end up spinning wildly just to do 35-40 mph. I have a 34-46 crank ordered so hopefully that will be the sweet spot. FWIW most of my other bikes are vintage with much taller gearing but I am getting older and need to make the hills more enjoyable.
Last edited by Duragrouch; 05-23-24 at 10:56 PM.
05-24-24, 02:22 AM
#55
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Why go just a 12 or 13 tooth jump on the crank? 16T is the defacto standard now and shifts well, 50/34 is very common, as well as 52/36. Both are common on a 110mm BCD. Smaller than 34 and you'll need a smaller BCD on the inner ring. These are all available in square taper cranks, but also hollow-spindle 2-piece crank with external BB bearings (similar to shimano hollowtech II), that's my personal preference, love the system. Needs to be correct length for your BB shell, 68 (typical road) or 73 (typical mountain).
FWIW the pic shows about the worst hill in the area where a couple sections are ~ 10% and I need to bail out with the 30t chainring,. Sorry about the file size, I wasn't sure how to make it smaller.
