Quoted post said:Originally posted by bryanquinn
Kevin,
Thanks for your response. If you go back to the initial thread I started you will note that my problem starts after shifting into the big ring upon running out of gears in the 39 tooth ring. This only happens in a group situation, it's the only time I'm able to travel fast enough to warrent shifting up. For some reason even though my cadence stays around 100 to 105 I seem to burn out rather quickly. This is why I started the thread. I couldn't understand why even with the cadence staying high I was burning out. Not because of an use related injury as some have suggested, (but I have taken all threads into serious consideration), and want to thank all who have contributed.
What I have gathered is that the amount of miles I have put in are not sufficiant enough to susstain the use of the 52 tooth ring. Right not I am fighting an illness that has hung on for three weeks now and I am sure I will loose a great deal of fitness and will have to start at square one again anyway.
Thank you all for your input.
BQ
BQ, I'm glad we've been of help to you. I fear I didn't make myself as clear as I would have liked in the earlier post. You wrote that you gathered that you didn't have enough miles to sustain the use of the big ring. With all due respect to the people who have told you that you have to have logged a certain number of miles before you can ride in the big ring, that idea doesn't make any sense if you look at the way bicycles are geared. It's like saying "I don't have enough miles on my car to go above 2nd gear." Because about half of the gears on the big ring duplicate, or are very similar to about half of the gears on the small ring, it doesn't matter which ring you ride in if you ride in this area of overlap which many people do.
Here's an example. The specific gears involved are atypical because I am riding with somewhat uncommon gearing but the idea is the same no matter how your gears are configured. My everyday setup uses 54-42 rings with a Dura-Ace 10 speed 11-23 cassette. I generally spin at between 95 and 105 cadence and my base gears (the gears I end up spending most of my time in) are within the 67 to 87 gear inch range. On my setup I can be in that range on either the 17 through 13 teeth cogs on the 42 ring or the 21 through 17 teeth cogs on the big ring. While I'm in that range it makes very little difference which ring I'm in because the gear range is the same on both of them (there are more steps between the high and low end of my range on the small ring and sometimes this makes a difference).
You said your habit has been to shift to the big ring when you run out of gears on the small ring. I'm assuming you're not cross chaining so you're shifting to the big ring after you reach the penultimate gear on the small ring. How many cogs do then drop back once you're on the big ring in order to shift up a reasonable step size? If you are moving to the big ring on the penultimate cog you should have plenty of lower gears available to you to fall back to with several of these gears being lower than the one you were in on the small ring. Riding in the big ring shouldn't be a problem if you're shifting correctly.
Part of the problem may be that you're waiting too long to shift to the big ring, you should make the shift sooner. When you move from the small ring to the big one you should almost always shift rings first and back off on the cassette second. If you back off on the cassette while still in the small ring, you'll lose momentum and get dropped like a rock. Shift into a bigger gear and then back off to the right gear and you'll maintain momentum if done properly. It may be that shifting at the high end of the cassette puts you in much too big a gear when you shift into the big ring and even though you're only in this huge gear for a brief instant, it's too much and you can't recover. Gearing isn't linear; a 1 tooth change is a larger change in gear inches in the big gears than in the small gears. For example, on my setup the penultimate cog is a 12. Dropping back to the 13 on the big ring is a loss of 10 gear inches while the move from 12 to 13 on the small ring is a loss of only 8 gear inches. Because of this nonlinearity when you switch to the big ring when you max out the small ring you're shifting into a huge gear, maybe too huge. The next time you're in a group ride you might try shifting to the big ring (and then backing down on the cassette to a comfortable gear) well before you run out of gears on the small ring. The transition should be easier. Practice and try out a bunch of combinations beforehand and see what works well for you.
All of this will be easier if you work out your gearing in terms of gear inches. Then you can see exactly what gear you're in and how it relates to the other gears that are easily available from your current position. I keep a little gear-inch table taped to my stem so I don't have to try to do the math in my head in the heat of a ride.
Hope this helps
--Kevin