February 5, 2009

Hill climb musings

So as many of you know, I am an idiot and am trying to break a very fast record time at the Winter Park Hillclimb.

I have 4.5 months left to get in shape (I’ve been “training”) since the start of January, and I’m still working on figuring out some good benchmarks to estimate how much faster I need to get.

I found this simple hillclimb calculator and I’ve been playing around with it this morning.

Recall that my time on this 5.3 mile, 2062 foot climb last year was 33:24. I also know that I weighed about 155 pounds and that my bike was roughly 18 pounds (a singlespeed with cyclocross tires).

Punching in all those numbers means that I put out about 340 watts (making the assumption that rolling and air resistance accounted for 100w) for the climb last year. Not too shabby at all, I think. I guess I don’t know that much about wattage, though.

One way to get faster is to lose weight. The bike can’t lose much – maybe a pound or so. So let’s say I go from an 18 pound bike to a 17 pound one. Result: an 11 second improvement. That’s not going to be enough.

But I can lose weight (and in fact I’m down to around 148 pounds now). So if we assume I put out the same power, ride a 17 pound bike, and weigh 148: Now I’m down to 32:02 (recall that the record is 31:14). That’s encouraging! In fact, it’s so encouraging that I’m putting this picture of Mike Rasmussen up on the wall in the shop as encouragement!

Erm. No. That’s disgusting. Sarah would kill me, assuming I hadn’t already died of malnutrition. Sheesh.

I think I can lose a few more pounds without sacrificing muscle or overall health. So let’s say I’m 145 on race day: the new predicted time is 31:27 – pretty much at record pace.

Alternately, how much power would I have to add at my current weight? If I’m 148 pounds, and I put out 345 watts: 31:22.

145#, 345W: 30:48!
140#, 340W: 30:28!
140#, 345W: 29:51 (ok, now we’re getting silly)

So basically, for every extra watt of power (at about 145 pounds weight) I save about 8 seconds. For every pound of weight lost (off bike or rider) at 340 watts, I save 12 seconds.

I’d like to both lose a few more pounds and add power (though since I don’t have a powertap, that’s hard to measure). And since the Winter Park climb is currently snowed under, I need some local goals that I can compare to. More on that in a week or two – there are several local climbs that might suffice as comparisons.