Compact Cranks - Yay or Nay?

Use this link to check gear ratio's of what ever you decide.  I don't know hardly anything about CC or what their advantages are but am pretty sure you can get the same gear ratios you need in a standard crank.

I have a set on one of my road bikes and I like them.

I was wanting to try out a compact as well. My idea is a straighter chainline in the big ring with less shift to the small ring. Would like to try a 50/39 as I am more than happy with the small ring at 39.
John.

I have compacts.  Like them.  It's the tighter cassette gearing that will probably make a bigger difference in your shifting (fewer 2 teeth jumps in an 11-23).  I went to the compact but ALSO moved from an 11-23 to a 12-25.  I was more interested in getting some more climbing gears (mostly for LP last year).

Based on your intial post I would say that compact cranks are not appropriate for you. The main advantage of compact cranks is that they allow an increase in range on the low end of the gearing spectrum, almost to what you get with a triple. So if you need lower gears then go for it. I have a compact and love it, but I need those gears. But you obviously don't need low gears if you are doing the relatively hilly IMWI with a 12/25 cassette in the back.

It is not correct that a 11/23 cassette is spaced closer than a 12/25. They both will have cogs spaced one apart on the 5 small cogs and probably spaced two apart on the larger cogs. If it is spaced any differently at all it is only between two if the cogs in the whole cassette. The difference in the shifting is definatley not in the spacing of the cassette.

The "space" between gears on on a compact crank is actually greater than a standard crank, not less, because the range from high to low is greater (i.e. the difference between chain rings is greater). Instead of switching the back cog three spaces you would have to switch 4 or 5.

But it is true that less shifting in the back is usually required on a compact, and that is because the large difference between the gearing ratio of the large chainring and the small chainring means that there is less overlap in gearing rations between the two chainrings. So instead of shifting to the small chainring you would just leave it in the big ring and only shift the back. In fact the difference between the large and small chainrings is so great that often people with compacts don't use the small chain ring at all except for extended climbs. Because it appears that you are pretty fit and don't need the low gearing you may never need the small chainring if you had a compact. But what you give up is the higher number of gears and the ability to get just the right gear.

If you do get a compact then definately get a casset with an 11 cog as you will not want to give up the high end of the gearing.

You already know my position....

Yay......all the way!

IMO an 11-23t and 34-50 is the perfect combo for most riding.

Edited by oipolloi 2008-02-09 8:38 AM