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Discussion Starter · #1 ·
Need some advice from some seasoned pros on gearing. I do a lot of climbing here in Northern Virginia and am on a Campy compact (50-34). I alternate between a 12-25 and a 13-29 on the back depending on the ride and how much climbing I'll be doing that day.

But I'm at a point where I'm spinning out of the 12-25 on the local weeknight club rides (I'm riding BB and would like to move up to A, but don't have the top end speed to keep with those guys on the flats). I was riding on Sat and was on the wheel of a very strong rider and was spinning out when we hit 37 on a false flat.

So my question - would you guys just drop an Campy 11t cog on the back or would you make the change up front? I was leaning toward just giving myself the extra gearing in the back rather than changing out the chainrings and losing the 34 up front for climbing.

Appreciate your thoughts.
 

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I'm no seasoned pro,

but I can do a little math. At 37 mph in your 50x12, you were spinning about 113 rpm. changing to a 52 would get you down to about 109. Changing the cog only, so you have a 50x11, would get to 104. And changing both, so you'd have a 52x11, would mean you'd be spinning 100 rpm at 37 mph.

So getting the 11 is obviously most bang for least bucks.

BTW, I've always heard the term "false flat" used to refer to a slight climb that appears flat. Am I to assume that here you meant a slight downhill? Or were you really going 37mph up a grade?
 

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Discussion Starter · #3 ·
JCavilia said:
BTW, I've always heard the term "false flat" used to refer to a slight climb that appears flat. Am I to assume that here you meant a slight downhill? Or were you really going 37mph up a grade?
Thank you. Appreciate the math lesson.

And yes, the road we were on starts off slightly down and then rises gently. The guy I was following was an absolute animal and ramped it up until I saw a top speed of 37. It was all I could do just to hold his wheel.
 

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I've often considered the same approach. I'm currently running 12-25 with a compact setup in the front. Can't seem to find 11-25 anywhere, though. 11-23 is common, but I live in hill country and I'd hate to give up the 25. Two options; I could replace the 12t cog with an 11t (Shimano), or I could install an 11-26, which I have managed to find. Either way, I'd change the cassette before I'd change the rings. Like someone else said, the cassette change is more bang for the buck. A change of 2 teeth up front is a 4% change, while a change of just 1 tooth in the rear is an 8.3% change.
 

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Discussion Starter · #5 ·
Just ordered the 11t cog...
 
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