Have bike, will travel
Join Date: Feb 2006
Location: Lake Geneva, WI
Posts: 12,284
Bikes: Ridley Helium SLX, Canyon Endurance SL, De Rosa Professional, Eddy Merckx Corsa Extra, Schwinn Paramount (1 painted, 1 chrome), Peugeot PX10, Serotta Nova X, Simoncini Cyclocross Special, Raleigh Roker, Pedal Force CG2 and CX2
Mentioned: 46 Post(s)
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"Compact" refers to the number of teeth, not anything having to do with chainline. In other words, the diameter is compact, not the width.
"Standard" cranksets have 53 and 39 tooth chainrings. Old-school standards are 52/42.
"Compact" cranksets have either 50/34 or 50/36 chainrings. These are generally paired with a wider-ratio cassette with an 11-tooth small cog so that the effective top ratio--50x11--is nearly the same as a 53x12.
Cyclocross cranksets are pairing 46/36 or 42/34 rings.
Your current touring triple and MTB cassette have much lower gearing than any of the above can ever hope to provide. There may be external bearing touring triples out there, I'm just not aware of any.
While all of the above is true, the ultimate determining factor that defines the two cranksets in the BCD specification. Compact Cranksets have 110mm BCD spacing and modern standard cranksets have 130mm BCD. The smallest chainring that will fit on a 130mm BCD crankset is 38t. The smallest chainring that will fit on a 110mm BCD crankset is 33t.
I have a Deore MTB "trekking" triple with Hollowtech II external bearings and 48, 36 & a non-standard 22t. This crankset is sometimes seen on touring models from Jamis and other.
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When I ride my bike I feel free and happy and strong. I'm liberated from the usual nonsense of day to day life. Solid, dependable, silent, my bike is my horse, my fighter jet, my island, my friend. Together we will conquer that hill and thereafter the world.
Last edited by Barrettscv; 09-02-12 at 04:27 PM.