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Cyclocross Gearing(16 posts)

Cyclocross Gearinglexington476
Jan 27, 2003 8:28 PM
I am building a cyclocross bike up from a Cannondale frame (the one without the head shock). What kind of gearing do people use on these kind of bikes? Two or three front chain rings? What would be the number of teeth? What about the back, and the brands used?
re: Cyclocross Gearingjhr
Jan 28, 2003 6:00 AM
At races, you tend to see mostly double cranks (38 or 39 by 46 or 48) and either a 12-25 or 12-27 in the back (well equipped guys may have all of the above options available and adapt the gearing to the course). You also see a large number of guys running single ring set ups (single ring with chain guards)either a 42 or 44. Single ring guys also tend to run a 12-25 or 12-27 on the back. You will see guys on triples but mostly in the beginner classes (these are the guys just out for some fun [really hurts when they smoke you on their 25lb triple equiped touring bike]). You will also see guys on single speed set ups.

If you go to Cyclocrossworld.com and click on the Riders link you can look at a number of pros bikes from 2002 and 2001 and see how they are set up.

Like with road equipment most guys ride Campy or Shimano drivetrains. I suspect the choice is based mostly on road bike compatability (ie if your road set up is Shimano then your cross bike tends to be). This allows someone to interchange parts between the two. When I buy a new toy for the road bike the part it replaces usually winds up on a cross bike.

Hope this helps. Good luck.

jhr
re: Cyclocross Gearingscruffyduncan
Jan 28, 2003 8:54 AM
I would say it depends on how you're planning to use the bike. I have a cross bike which is normally set up for the road with mudguards, slicks and even a rack, with 39/48 front and 12- 26 rear. The only times I use it off road are on canal towpaths, bridalways etc or when actually racing. Occasionally during a race I wish I had a lower gear but the races only last an hour so I usually stomp through (after all I am supposed to be going as fast as I can). If you are looking for an all purpose bike to be used for longer off raod rides, i'd recomend much lower gearing, getting up a steep slope in the mud can be hard work.
re: Cyclocross Gearingatpjunkie
Jan 28, 2003 1:10 PM
It also depends on your local courses, and intended usage. Have 2 bikes and this season I rarely used the 48 that much. Could have gone 46 or 44 comfortably. Have Bike 1 which is set up as a double (48/36) up front with a 12-30 (MTB 8 speed cassette) I'm a bigger rider so I like the extra gear in back. My other bike, which also serves as a commuter/adventure/trail bike runs a triple 48/36/26 with a 12-27 cassette (9 sp). I rarely use the granny ring up front (only once in a rather hilly race or) on Adventure rides. If your riding will mostly be flat and you are 'fit" I'd say run a single 42 with a 12-27. Otherwise go 48/36 (my pref.) and 12-27.
single front pretty good for most racesweiwentg
Jan 28, 2003 2:45 PM
atpj' right, if you're in shape and this is to be a race-only bike, a 42 front and 12-27 back will be fine. if you're planning on using this as on the road at all, go 48-36 or -38. if you're Sven Nijs, go 53-39 (just kidding).
in races, people will usually run up the hills that are too heinous to ascend with regular double gearing.
Heck, single <i>speed</i> good for most races, if you're ...GlowBoy
Jan 29, 2003 12:13 PM
out there for the fun of it and not necessarily to win.

Or if you're SS_MB-7, even if you are in it to win it.

- Dan
Heck, single speed is good for most races, if you're ...atpjunkie
Jan 29, 2003 12:31 PM
out to destroy your knees.
kidding
big ups to the SS fanatics!
re: Cyclocross Gearinglexington476
Jan 28, 2003 7:51 PM
What does two chain rings get you over three? Three can not weight that much more.

I am thinking about using the bike for CX, and also using it as a regular bike as well (maybe trail, road, and/or touring).
re: Cyclocross Gearingatpjunkie
Jan 28, 2003 9:24 PM
it's only advantage (2 over 3) is there's less chance of error during shifting. It's why most racers run a single. You can't really drop a chain when you've only got one ring with guards. You'll see when you are racing (if you choose to do so) and you'll set your bike down after running through some barriers and hopping on gasping for breath and trying to maintain a lead over somebody only to step on the pedal and get nothing as your chain is sitting on the BB shell. VERY FRUSTRATING
I dropped chain (twice on my double set up, once on the triple) and it cost me a shot at first (couldn't make up the time lost),
sent me from 3rd to 9th (fought my way back to fourth, but could have had a second) and the third time (after practicing my "flying rechaining technique" thanx to my friend who showed me cost me only a second or two.
most cx races aren't that hilly and the hills that are so steep you'd need a granny ring you should run as it's faster than pedaling. If you plan a multi-use bike by all means run a triple, the traditionalists be damned.
This retro-grouchiness is why you'll get 'looks" at a cx race running a triple. Like Campyphiles poo-pooing the Shimno-ites etc...
I have one of mine set up like that for this reason. The double I may switch to a single though.
friendly suggestionjhr
Jan 29, 2003 9:57 AM
I ran a double all year (38-48) without a single dropped chain using one of those $8 anti chain drop devices. You know what I am talking about. a piece of black plastic that clamps around your seat tube. It has a nose that redirects the chain back onto the small ring. Take a look at photos of from European road races and you will see a surprising number of these things on Pro's bikes. I adjust the front derailer so I get a slight rub in the 48x12 gear to prevent overshift going to the big ring.

On a supper muddy day, I just commit to using only the small ring. The big ring and anti chain drop device act as chain guides. The 48 is very handy to have on any course with a long road section (especially a long downhill road section like Monkey Hill in Delaware). I even did one race this year (flat very fast course) entirely in the 48.

Another reason why triples are more likely to drop a chain is that to accomodate the wide range of gears and long derailer cage they generally have pretty long chains. Dropping the front derailer into a 30 tooth chainring creates a lot of slack in the chain increasing the chances of droping it.

jhr
friendly suggestionatpjunkie
Jan 29, 2003 12:30 PM
yes I put a third eye on my double bike as well. (after chain drop #2) The CA State Champs had a long straight as well as our last race (not paved but hard dirt) and I loved having the 48 for hammering. yes, understand bigger cogs equals longer chain. It's the price I pay being a 'big boy". at 230 a 27 doesn't quite mean the same to me as it does to most
re: Cyclocross Gearingjrm
Jan 29, 2003 8:00 AM
Im using a LX compact triple and a 12-27 cassette. Its not the lightest thing but it works.
re: Cyclocross Gearingdlbcx
Jan 29, 2003 8:30 AM
The reason is that you don't want to be doing very much shifting on chainrings. I have seen more guys drop a chain or jam it when they attempt shift in the chainrings. So, single ring is the ideal way to go, if you are going to race more than a few times a year. But, for most of us, two rings work the best but as someone said, when it gets steep, it is time to start hoofing it.
was 38/48 & 12-25TCN
Jan 28, 2003 2:49 PM
But then I got tired of pushing the bike so much and went to 38/48 (same Ritchey crankset), and a 12-34 cassette. Not too much need for a triple where I live and the 34 helps out greatly.

BTW Cassette is XT and the rear deraileur is XTR and they replaced ultegra's on the previous gearing.

Just about perfect for my riding style now.
re: Cyclocross Gearinglexington476
Jan 29, 2003 4:35 PM
I am thinking of using this bike to race CX, extra road bike, and maybe even on an MTB trail with the right tires. I do not have the money (or room) for too many bikes; this one will bring me up to four (road, old MTB, new MTB, and the CX). So, I guess I want to have it lean towards CX racing but I still want to be able to use it for other uses with out having to change it every time. I will be racing/riding it in Michigan USA. I am just getting the frame but it comes stock with Shimano Tiagra 9-speed, 12-25 and TruVatiV Elita Cyclocross, 39/48, maybe I will just put those on.
re: Cyclocross Gearingatpjunkie
Jan 29, 2003 5:56 PM
switch the cassette to 12-27 and you'll be fine. It will work for road/cx and most Michigan Trails