|Lose the 12 or 13?||LC|
Jan 24, 2002 10:18 AM
|I got 16 cog that I want to work into a 12-25 or 12-27 Dura Ace cassette. I live in a very hilly area, so I do need at least the 25. Something has to come out, so do I remove the 12 or the 13? I have a proper 13 with a lock ring from another cassette, so any mechanical problem is not an issue.
I can't see needing the 13 all that much, since usually it is only on steep downhill that I would use it, and then would'nt it be better to have the 12 so I don't spin out? Do I need the 13 for sprints? This will be my first year at serious racing, so I don't know what to expect.
Jan 24, 2002 10:32 AM
|if you are racing, you WILL need the 12. an 11 would be even better for slight-downhill pack sprints. Our Sunday group ride finishes with a slight downhill pack sprint, I always spin out my 53/12.
If you are a beginning racer (sounds like cat 5 ?) you probably wont see those kinds of speeds, but you will want at least a 12 for the fast stuff.
My advice is to keep the 12-25 or 12-27 as-is and be done with it. When you start mixing cogs, the shift quality will deteriorate because the shifting ramps wont line up and/or you might have too large of a tooth gap to bridge.
maybe try to get a 12-14-15 or maybe 11-13-14-16 worked out if you cn line up the ramps on the gogs. Some grinding of the wide cog-alignment tab might be needed.
just remember, when you are racing in a pack, your speeds will be nothing like the speeds you see when riding alone or with a couple buddies. You will be going so much faster.
worry less about your "custom" gears and just concentrate on good pack skills, smart race plans, and your form. enjoy it as-is.
|re: Lose the 12 or 13?||mclements|
Jan 24, 2002 11:00 AM
|My favorite Shimano combo is: 11-12-13-15-17-19-21-23-25. It has a wide range with smooth ratio transitions. They don't make one like this but it's easy to build yourself.
If your primary goal is to build a cog with useful gear ratios, then I'd recommend building whatever ratios work best regardless of whether it incorporates your 16 tooth ring.
|re: Lose the 12 or 13?||pa rider|
Jan 24, 2002 11:14 AM
|If you can get the 16th gear to work, then do it. One of our club riders races cat 2 and said he uses the 16th gear alot on his record 10 speed.
|re: Lose the 12 or 13?||gtx|
Jan 24, 2002 12:16 PM
|keep your 12-25 for training and use a 12-23 (or a 11-21 or 12-21) for racing. If you have to resort to a 39x25 in a race you're probably gonna be off the back.|
|16t, If you don't use it I'll buy it.||Chen2|
Jan 24, 2002 1:30 PM
|Provided it is a 9 speed cog. I'm trying to build a 13-27.