|Time Trial Gearing||trisnob|
Jul 27, 2001 2:41 AM
|Regarding gearing for a TT bike, I'm currently using 53/39, 12/25 on my bike. At a local TT hear in SoCal, I hear racers saying that (so and so) "...ran with a 58 tooth big ring for this flat TT and changed back to a 53 for a more hilly TT" I've been riding for awhile, but I'm a newbie when it comes to technical aspects of road bikes, but what I am hearing is that a really big ring up front will allow you to fly, provided you can push those big gears. So I go to a local bike shop near Ventura and ask them about getting a 56 or 58 big ring for my bike and they say "Oh, you don't want to do that".....Huh? My experience is that most bike shops don't know much when it comes to racing road bikes, or TT/triathlon bikes, so I ask the experts here to explain the advantages (or disadvatages) of running a 56t (or larger) ring at my next TT. Also, what kind of gearing do the fastest riders on pro teams use on their TT bikes|
|re: Time Trial Gearing||burnan|
Jul 27, 2001 4:23 AM
|I wouldn't change what you have. Can you turn a 53x12or11 on flats? I know I can't. I would put my money into something else for now. I would assume that the guy who ran the 58 has been training/racing for some years or its an image thing. That's my 2 cents. Goodluck in the TT...burnan|
|re: Time Trial Gearing||jp2|
Jul 27, 2001 4:45 AM
|just yesterday i was doing my own practice tt. with a tailwind, on the flats, a 55x12 let me cruise along at 35mph@~95rpm. it is easier to turn a 55x13 than a 53x12, which allows less extreme chain lines.|
|re: Time Trial Gearing||trisnob|
Jul 28, 2001 3:19 AM
|When you say "less extreme chain lines", does that mean a 55t would be unsuitable for day to day riding? I can push a 53x12 in the flats, no problem and somtimes, i'm spun out on the declines. I heard Paul Sherwen say that at yesterdays TT on the Tour most riders were going with a 55T. Is there an ideal set up for TT and daily riding? Again, i'm a newbie regarding this techincal stuff, so I really appreciate the sharing of knowledge. Thanks|
|58t for real men?||Kerry Irons|
Jul 27, 2001 5:12 PM
|Assuming your TT idol is running a 12t in the back, he would be able to hit 34 mph at a comfortable 90 rpm. With an 11, make that 38 mph. Can you hold 34 mph (or 38 mph?) on the flats? The pros rarely ride such a big gear, as they know how to turn higher rpm (54/12 at 100 rpm = 35 mph, etc.). Your gearing has to match your abilities, and unless you are able to turn such a gear, leave it to those with larger egos.|
|re: Time Trial Gearing||CarbonRide|
Jul 31, 2001 9:24 AM
|Here is a twist on this discussion. I rode a 40K TT in June on a flat course in 39 x 11 - 16 at 100 + RPM. I did this because I knew I could sustain the effort for the whole distance. I got a time of 1:09.
Prior to and after that TT I did 10k practice TT rides in 53 x 11 - 15 at around 70 - 80 RPM. My times were around 14:30 min.
Obviously I'm a lot slower than the rest of you but I have a valid point. The gearing choice should be a result of your known sustainable efforts at various RPM, in particular gearing, over a particular time.
Aug 2, 2001 7:52 AM
|if you can turn over that large a gear (58/11) go for it but remeber that your smallest gear will be a 44/25 which may be to big if you blow up from turning that big a gear. Dont run it if you can spin it. Test a gear such as a 54 or a 55 tooth before you go to a 58 tooth.
In comparison to the pro's focus on spin, they all turn AT LEAST 95 rpm. the winners of TT's are spinning a 105-120 rpm.
I ride a 54/44 chainrings and a 11-23 cassette and move at 85-100 rpm
|re: Time Trial Gearing||jayh|
Aug 3, 2001 10:07 AM
|I would say definitely switch to an 11/23 first. At Willamette, Moninger (Mercury) powered a 57T to win...I've never heard of anyone using a 58T??? I ride a 55T and spin at around 85-90, certainly I could go higher...until you're winning Cat I or Masters A time trials CONSISTENTLY, I'd stick with 53T or 55T.|| |