I want to ride faster

[Veronica]

You will go faster *for the same effort* on a lighter bike, especially where climbing is concerned. That is because speed depends on your power to mass ratio.

And you have to decide how much are you willing to spend for the two or three minutes you may save by getting a lighter bike.

Here's a calculator that shows you how much faster you can be with a lighter bike.

http://www.kreuzotter.de/english/espeed.htm

Use a ride you have some data on and plug in the weight of your bike and then do the same thing with what you think a new road bike would weigh.

V.

[Triskeliongirl]

I agree that often folks have unrealistic expectations when they move from a 20 lb bike to an 18 lb bike, or 18 to 16. BUT, moving from a 25 plus pound bike (typical hybrid) to 18-20 will make a difference. So will moving from a hybrid to a road bike, where in addition to weight savings, she may get a more effecient position (with proper fitting), a more aerodynamic postion which can cheat the wind, more hand positions, etc. I do think that someone who is averaging 14-15 mph on a hybrid is probably topped out, and will benefit from a move to a road bike.

[Veronica]

That's why I posted the link to calculator. She can play around with all the numbers and various configurations and decide how to spend her money.

I know I put out 188 watts. When I put my data into the calculator and say I am on a mountain bike with medium slick tires it would take me 5 more minutes to do my local climb.

Is five minutes on an 11 mile ride worth a couple of thousand dollars? That's something she has decide.

Also how long is she spending on the bike? Is she averaging 15 mph on a 30 minute ride? Or a 3 hour ride? That makes a difference as well.



V.

[kelownagirl]

Cool link Veronica! I don't know how many watts I put out but according to the chart, it varies between 148-198 depending on whether my hands are in the drops or not! Interesting!

How to do increase my "wattage"? Just ride more? Is it something one can improve?

[Veronica]

Last year based on the same ride I was putting out about 160. My improvement came from riding hard, medium distance rides.

V.

[Cassandra_Cain]

In the flats, by far and away, the biggest limitation is aerodynamics. Whereas on a climb, more so the steeper it gets, power to weight is the biggest limiter while aerodynamics becomes rather secondary.

I could for example, put a 25 pound plate in my backpack, and to ride at 20mph would only need to produce about 4 more watts than I do at my present weight.

Meanwhile, if I tried the same stunt on a 5% grade, to ride at 10mph, I'd need to make 25 more watts.

You can see this in practice because drafting on a climb saves you much, much less than in the flats, where you can ride with much stronger riders just by sitting in and staying out of the wind.

I think average speed in the flats is a rather vague number to use as a measure of fitness. On a climb, that you do regularly, then it can be really useful since aerodynamics & wind have a lesser effect.

Using calculators for climbs has an important limitation - when you plug in the numbers, % grade, etc - the assumption is that the climb is steady, and I've yet to see a climb of any significant length that fits such a description.

Where I do a climb locally that averages about 6% for 10+ miles, segments range from a short downhill to over 10%. So in reality, my power numbers are higher than what the calculator predicts because of the variation in terrain.

There are many, many ways of getting faster. Veronica mentioned what worked for her. My preferred method consists of 10-40 minute intervals at TT (1-hour) pace several times per week.

[alpinerabbit]

Interesting - why does low air temperature increase my calories burnt on that link?

Correlates with what I felt today after a 60 km ride at 10°C - trashed....

[Veronica]

Using calculators for climbs has an important limitation - when you plug in the numbers, % grade, etc - the assumption is that the climb is steady, and I've yet to see a climb of any significant length that fits such a description.

You need to come to the Bay Area then.



This is a fairly steady grade. There is one spot around 2,000 feet where it kicks up to 9%. The last tenth of a mile is 17%. Otherwise it's fairly steady 5 to 6 % for 11 miles.

V.

[SadieKate]

I think average speed in the flats is a rather vague number to use as a measure of fitness. On a climb, that you do regularly, then it can be really useful since aerodynamics & wind have a lesser effect.

Wow, I'm just muddling through this thread. Since all I have is flat roads to ride, my shorter ride times over a season and in flat time trails don't mean anything? The same 33 mile ride ridden over the years has gone from a 2.5 hour effort to a fairly consistent 2 hours. Why wouldn't this be a measure of my fitness?

Using calculators for climbs has an important limitation - when you plug in the numbers, % grade, etc - the assumption is that the climb is steady, and I've yet to see a climb of any significant length that fits such a description.

The Sierras and the Cascades are full of long, steady climbs.