GeoB said:
Quoted message said:Let me know how you like the crank as I just bought one.
I'm a newbie, please explain this to me! What is 'sweet' about a crank and arms? Lighter? OK.. but
how would one isolate that from the over-all newness of the bike? What's great about cranks?
Special bearings? Less friction?...
The bearings are in the bottom bracket (crank spindle) which is separate from the crank itself. [1]
There are several factors that can be measured objectively that will make a difference between
cranks. One obviously is weight. The two that are most important are crank arm length (much debated
as too effect) and "Q-factor" which determines (along with the bottom bracket spindle length) the
horizontal distance the pedals will be apart.
Chainring design can also be significant. [2] "Ramps and pins" will assist in shifting up to a
larger chainring. This is more important with indexed shifting, especially with Shimano
Rapid-fire shifters.
As for the importance of the visual characteristics of shape and finish, that is totally dependent
on the owner's value system.
[1] The are several different ways to attach the cranks to the bottom bracket, so not all cranks and
bottom brackets are compatible. Refer to < sheldonbrown.comglossary.htmlOpen ↗ > for more
information.
[2] There are also compatibility issue between cranks and chainrings - bolt circle diameter (BCD)
and bolt pattern (5 bolts are standard, but 4 bolt MTB cranks are fairly common).
Tom Sherman - Quad Cities USA (Illinois side) RANS "Wavewind" and Rocket, Earth Cycles Sunset and
Dragonflyer