|cassette questions||Pyg Me|
Jun 4, 2001 9:29 PM
|I live on the Gulf Coast so hills/mountains are a rarity. There is nothing around here that I can not handle on my double (53/39 w/11-23 cassette.
Recently I made a bike trip in the "hill country"-Leakey area to be exact- and I encountered the steepest/lomgest climbs of my riding life.
Although, I was able to climb even the steepest ascents with my granny and the 23, I certainly would have liked to have a couple of more teeth in the rear.
Towards the end of June, I am riding from the Houston area, to LA and then New York with 16 other people. I want to carry another cassette for the climbing legs. Any suggestions? Stay Ultegra and go 25? Will a MTB cassette work?
|re: cassette questions||Rusty Coggs|
Jun 5, 2001 7:15 AM
|If you have 9 speed,the max road rear cog is 27 teeth. If you go with a bigger mountian cassette,you will likely need a mountian detailer to handle the larger cog. If you have 7 or 8 speed, I have run a 30 tooth rear cog with a short cage 105 or ultegra 7 and 8 speed derailers, which I believe, were rated for 28 teeth,but typically will handle a few more. You may need to lengthen the chain and fiddle with the B tension adjustment.Running just a 25 in place of the 23 lould likeky involve no changes.|
|And lose the 11 - you don't need it, do you? (nm)||Kerry Irons|
Jun 5, 2001 6:08 PM
|And lose the 11 - you don't need it, do you? (nm)||Pyg Me|
Jun 6, 2001 9:00 AM
|Actually I have considered going to a 12, but decided not to. Like I said, the Gulf coast is kinda flat. I ride with a crew that has not problem rolling along at 30 mph for stretches at a time. Not that I can pull for that fast without considering it a sprint. But, when we get up to that speed, I have used all my gears and I am spinning out. Eventually, I'll use the big ring in front,,,,,just kidding.
I'll have to reconsider the 11-23 and maybe go with a 12-25.
|And lose the 11 - you don't need it, do you? (nm)||TSTAMM|
Jun 6, 2001 11:01 AM
|i have the same problem, i live on Long Island, not a problem with 11-23 cassett. I recently went to Vermont and died on some of the steep hills. I was thinking about either going with a 12-25 or 12-27 cassett. Any thoughts, is this going to be a problem for my chain or rear derailler?|
|Excuse me?||Kerry Irons|
Jun 7, 2001 7:55 PM
|You can ride at 30 mph and need lower gears for the hills? I don't think so. And even at 30 mph, a 52/13 only requires 90 rpm. So, not much of this adds up, but it makes a great story. BTW, it's not been that many years ago that the hour record was just over 30. You guys should be in the pro ranks for sure.|
|Kerry, I've got an 11-23 cassette, and I use the 11 all the||bill|
Jun 8, 2001 1:27 PM
|time -- on the rollers. Now that I've actually learned how to pedal my little bikey, thanks to rollers, I realize that an 11 is for another species of human, and I can't remember when I went to 11 (remember Spinal Tap?) except screaming down some hill where I'm not sure that I was doing anyone any good by pedalling. The question now is, do I get a 12-25 or a 13-26 (I'll get a Chorus 10 sp. cassette, the rest of the drivetrain is Record -- yeah, yeah, yeah, I got the good stuff before I knew how to use it, sue me). My normal riding is pretty flat, little rollers, where the 23 is plenty low, but I sometimes take the bike to my in-laws in CT, which has some genuine, bona fide, kick your ass hills. I've made it up them with a 25 (set up on a set of Cane Creek wheels, long story), but I'm wondering whether, to make it worth having another cassette that I will use pretty much only when I go hilly, I just should go 13-26 for real contrast. Or maybe that's stupid, because 26 or 25 isn't going to make that much difference, and I'll miss the 12. As far as intermediate gears, I'm not in love with any in particular.|
|Excuse YOU....||Pyg Me|
Jun 9, 2001 2:02 PM
|....And learn to read also. My post specifically stated that If I am at 30, I am sprinting. Not just riding along. It also said that those guys pull at 30 for stretches at a time, NOT AN AVERAGE SPEED. I am just hanging on at this point and spinning out. Not everyone has the same spin Mr Wizard.
As a matter of fact, two guys I ride with are Cat 1's and one is a pro, who at the time being is in Belgium on the race circuit.
I guess that you are the only person able to ride 30 mph as exhibited by your vast knowledge of the rpms of a 53/13 to go 30 mph (Of which I think is full of crap.)
|Basic Math||Cliff Oates|
Jun 10, 2001 5:16 PM
|I guess that you are the only person able to ride 30 mph as exhibited by your vast knowledge of the rpms of a 53/13 to go 30 mph (Of which I think is full of crap.)
It's easy enough to calculate. Take the gear ratio times the circumference of the tire in inches times cadence and divide by 12 to arrive at feet per minute. Multiply that by 60 minutes and divide by 5280 and you get miles per hour. For example, 53/13=4.077 * 26.34"*pi (the approximate diameter of a 700C wheel shod with 23 mm tires times pi yields circumference) * 95 rpms and dividing by 12 inches returns 2670.8 feet per minute * 60 minutes in an hour and dividing by 5280 feet in a mile and you get 30.35 miles per hour.
A 53/13 combo yields 30 MPH at an efficient cadence of 95. 53/11 has you going 30 if you drop your cadence to 80 rpms. A cadence of 80 is hardly spinning out.
Jun 6, 2001 4:10 PM
|Carry a 20-28 front chainring. You will get better results in the mountains. The difference is tremendous. Run it with your 39. Later go back to 53/39. Rear? Get no less than 13 and the biggest without changing d-rail, probably a 32.|
Jun 10, 2001 3:31 PM
|You are riding around 8 thousand miles, right? You won't be sprinting much, I'd say.
I'd get a 12-27 and 53/38 up front. Unless you are carrying a big load, that should work anywhere. Don't carry the extra cassette, just use the above set up.