Crankset Options and Understanding

[Jay]

Is there a site or youtube channel that explains crankset specs and compatibility (like all about them and how they work with a drivetrain, and frame).  It's one part of the bike I really don't understand.

Reason I'm asking is that at some point, I would like to switch my black GRX 2x crankset on my Roadini to something silver in colour.   But I want to understand this from a 'system' perspective vs. individual parts. Also, I really just want to understand how they match up to bottom brackets, BCD, spacing for the frame, how they interact with the different speeds (e.g., can a 10 or 12 speed crankset work with an 11sp drivetrain?), crank arms vs. chain rings and compatibility, etc., etc.  I want to learn up front now, so I can think of this longer term and when I come across a part that meets my future build ideas, on sale, I can confidently pull the trigger.

Feel free to share your wisdom here too, but I was asking for reference sites/channels so I learn on my own, over time.

Thanks!

[Steve]

Jay, you might start with Sheldon Browns website. He offers several discussions regarding all things crank. Here's a link to one:

https://www.sheldonbrown.com/cribsheet-cranks.html 

The thing about cranks is that as simple as the basic mechanical concept is, the variety of design approaches does make it all a bit overwhelming. If you stick with Silver cranks from RBW you can't go wrong, and you'll always have  this group and RBW for tech advice. (If retro style appeals to you you should also look at Velo Orange cranks)

Steve

[Ed Carolipio]

I recommend understanding the concept of a chainline first since nearly all the design choices and options you mention about cranks involve a builder maintaining a target chainline. Here's a good write up: https://bike.bikegremlin.com/1755/bicycle-chainline/

For "speed" (7/8/9/10, etc.), that is driven by the dimensions of the rear cassette, i.e., the rear cog width/spacing + teeth height/width/spacing. The dimensions in the chain and the front chainrings/crank come from those dimensions. Sometimes there's enough "slop" or margin in the system that combos for which the manufacturer will not guarantee compatibility (e.g., 9 speed cassette and 11 (road) speed chainring) can be made to work.

--Ed C.

Redondo Beach, CA

[Victor Hanson]

don't think of it in crankset size, think of the tire size you want to use.  Anything over 45mm is mtn and requries a 52mm chainline.   38-44 is the trick, this could be mt.  but a lot of cross/gravel cranks.   What dirve train impacts the use.   32-35 is definite cross territory and 46-48mm chainline should work.  Good luck

--
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 rbw-owners-bun...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/rbw-owners-bunch/cffaf80c-fe61-4e23-b54a-154428728958n%40googlegroups.com.

--

VIctor R. Hanson

Gen Mgr

Schmier Industrial Properties

o:  510-652-0800

c:  510-207-8593