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Scary Teddy Bear
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Okay, I have a 46/36 crankset now, and I am wondering about the cassette gearing....Would it not be better to use a 12-27 instead of a 12-25 for cross, as when you get into the thick mud and muck that lower gear may be lifesaver, or should I stick with a 12-25 (currently on)? What do you guys run?
 

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More Cowbell!
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physasst said:
What do you guys run?
Bike 1: 48/38 and 12-27
Bike 2: 46/39 and 12-27

When I get around to buying new rings, I'll probably go with 48/38 all around. There used to be a race around here where guys put on 11-34 cassettes. But that venue is too small (parking) for the size of the races now.
 

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tdiclub Member
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Bike 1: 44 or 46/ 39 and 12-25 or 13-26
Bike 2: single 42 and 12-25 or 13-26

Cassette depends on what wheelset 12-25 or campy 13-26

If you've got a 36 inner you have no need for anything higher that 25 on the cassete,
for racing that is.
 

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Go by the numbers below. Most everyone races on a 39x25 or sometimes a 27, which is 42 inches for the popular 25 tooth option.

Now, you have the 36, so checking the numbers below, you can clearly see that what you need is the 23. This is nice because you have closer ratios, but can be a pain beacuse you may have to make more front derailer shifts. Running the 25 would be an option, but would be a pretty low gear, lower than most people need for racing. A 27 would be pointlessly low for racing on normal courses. My vote is for a man sized 11x23 given your 36 front ring.


36x23=42 inches
36x25=38.9 inches
36x27=36

39x23=45.8
39x25=42.1
39x27=39
 

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Game on, b*tches!
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Bein a relative "noob", I've found that a 39x27 or equiv is about all anyone would need.
 

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More Cowbell!
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jroden said:
My vote is for a man sized 11x23 given your 36 front ring.

36x23=42 inches
36x25=38.9 inches
36x27=36

39x23=45.8
39x25=42.1
39x27=39
This is phys' first year racing. He is a clyd by any definition. I'd stick with the 12-25 if you go with the 36 up front. With that 36, you will be shifting the front mech more than you would if you had a 38 or 39. My race bike is a 38/48 and I stay in the 38 A LOT and I'm middlin' quick. The extra shifting up front will be a pain, IMHO.

I think the bottom line is that since it's your first season, go with what you've got. See what you think and switch things up in the next off season if you think you should.
 

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kajukembo said:
Dale Knapp uses a 44 big ring and he's my idol. So yes you guessed it, I use a 44 big ring, 38 small with a 12-25.
That's pretty funny, I remember looking at his setup one race and noticing the 44, I rode with a 48 last year and didn't like it for our courses so switched to a 46 for this year, but the same thing popped into my head, if its could enough for Dale well.....
 

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I have a 25 and 27 on 2 sets of wheels that I always seem to be swapping around and end up using either one almost at random many weekends due to my last minute disorganization about getting ready--I have not noticed this huge difference once the gun goes off, I have done a couple races with a steep hill that I had to run w/ the 25 while another guy next to me rode up with the 27--we both climbed at the same velocity, but then I had to clip in.
 

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Race bike: 42 x 12-27
Pit bike: 39-46 x 12-27

There are very few times that I've ever felt I was undergeared with the 42. And I've never felt overgeared with it. Flip side of the coin, I almost never use the 39 on the pit bike, but the 46 can sometimes feel a bit much. I'm a big fan of the single 42.
 

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well as a Clydesdale

I tend to like the 27 as you little f'ers don't know what it's like haulin 200 plus pounds up hilly cx courses for an hour. At equal wattage for every 15 lbs over 180 or so you lose about 300 ft per mile on a 10% grade. Come the final 15 minutes of a race it's nice to have that gear to help the legs turn that f'er over as you are already in lactic hell just from hauling yer big ass around at 90 plus percent of your max HR trying to keep up.
Bike 2 has 46/36 and an 11-28 8 speed. Now you guys might be saying hills what hills?
we our races got em and Cycloscott think Infineon 2 years ago. half the course was uphill every frickin lap. climbing the scree at the bottom wasn't bad but then you'd hit that wet grass, at 200 plus one word comes to mind.OUCH!
 

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Infineon. Hated that course. Even if I did relatively well there. I swear that grass was merely a decoy sitting on top of glue. And those stairs were a crap shoot. Pick the wrong side and you were stuck behind somebody without being able to pass. There was simply no place to hide on that course.

My favorite hilly course will always be Surf City at Aptos High School.
 
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