Hi everyone, I've been loosing weight this summer and between weight watchers online and the bike, I've lost 30 pounds so far, and I look better in all of my clothes, which makes me happy. However the bike is no longer a tool for weight loss, as I really enjoy riding for many many more reasons now then just weight loss.

My question is how much speed should I gain by loosing weight? I really haven't sped up much despite loosing a significant portion of my spare tire, and I'm still getting dropped by my group on the hills. I can keep up easily on the flats and downhills, which is why I was hoping the lower scale numbers would help me out.

Thanks.

Less weight doesn't necessarily equal more speed. If you want more speed, you have to work for it. Do some intervals, train with a power meter (or HRM). You aren't going to miraculously be able to keep up with the skinny guys just because you lost a few pounds.

Pretty much this.

I'm in the same boat as you and my speed has skyrocketed. But if you just casually ride and don't push very hard, you won't get stronger. Climbing favors the lighter guys a lot. Climbing is also heavily relies on technique as well.

Weight loss has a impact on climbing for cyclists. A 30 lbs weight loss will make climbing faster and it will improve endurance on hilly routes.
A 250 lbs cyclist, producing 150 watts, can maintain a 12 mph speed rate up a 1% slope. A 220 lbs cyclist, producing 150 watts, can maintain a 13 mph speed rate up a 1% slope.

It's not much, but it can add up on a long ride.

jay: can you quantify skyrocket?

Hills are your enemy; hills are your friend.


Find some. Do them. A lot.

The best way to get better at climbing hills is to climb hills.

Google up some info on hill climbing advice. There's a ton out there. How you position yourself in the saddle, what gear you pick, when to stand vs sit... there are a lot of different techniques that different riders use. Find some techniques, experiment with them. Figure out what works best for you. Then, experiment with others, too.... because on long hills or rides with lots of hills, you may want to switch it up some.

A story: I have some fitter friends that I sometimes ride with, they have to wait at the top of every hill for me. I'm about 240 right now, they're "regular-size", fairly fit guys, maybe in the 170-190 range.

One of them told me yesterday he was riding with a group, and there was this amazing rider who could climb hills like nobody he's ever seen before. Eventually my friend also got to the top and was talking to this guy, "Wow, you sure are fast on hills. Maybe if I lost 10-20 pounds, I could be at a point where I could, maybe not keep up with you, but at least keep you in my sights! So how much do you weigh anyways?"

Answer: 130.

Yeesh! That's barely more than half of me.

I challenged my friends to strap on a backpack with 50lb of rocks and then we'll all go ride some hills together. I wonder how that would work out? So far I haven't been able to convince them to try.

Except up-hill.

A 215 pound Clydestale who ceases to be a hoss via a 30 pound weight loss and rides a 20 pound bike will be 15% faster up steep hills.

I have lost about 50lbs since I started cycling. The combination of weight loss and increased fitness from riding have been showing in my ride speed.

Sunday, I did an 11 mile training run on the '83 World Tourist with an average moving speed of 16.93mph. That is the best speed I have ever clocked (I count time from when I leave the driveway to when I stop at the front steps.)

Today, I did my 21.3 mile commute in 1h28+m with an average speed of 14.5 mph! That is awesome for me My first commute was about 12.5mph.

Therefore, my conclusion is that weight loss + increased fitness = faster average times.

Don't forget that your heart and lungs don't have to work so hard as you get smaller. Also if you've been loosing weight, it's probably because you've been living a more healthy lifestyle. These things and more will contribute to your speed a fair bit.

Hill repeats. That's really all there is to it.

https://bikecalculator.com/veloUS.html

Here's some purely academic calculations based on myself (360) and my target weight (200), with a 30 pound bike, and 150 watts average.

The first thing I notice is that based on weight alone, with no grade and no wind, I can go 8% faster if I drop 160 pounds. That's not what I would consider especially significant, but 1.32mph is 1.32mph. That'll cut 6 minutes off my morning commute... assuming it's all flat. But it's not, there's a lot of small little inclines of 1-2% grade.

The noticeable thing is how much speed drops off as soon as a grade is introduced. The tiniest amount of hill suddenly increases that 8% gap to a whopping 31% gap. That's much more significant. Now we're looking at a 27+ minute difference in my morning commute. The higher the grade gets, the more the gap increases too.

This is why there are weight weenies. To a pro racer, who goes up 15% inclines on Le Alpe D'Huez, even a single pound makes a world of difference in speed. When we're talking 100 miles in a stage, it adds up. As Depeche Mode once said, "Everything counts in large amounts".

Sample calculation. 130 pound rider, with a 15lb vs 16lb bike. 20 miles at 8% grade. That's a tough mountain right? But something that the pros probably do. 15 pound bike goes 5.67mph. 16 pound bike goes 5.63mph. Tiny tiny difference. But... over 20 miles, 15lb bike finishes in 211.79 minutes. 16lb bike finishes in 213.14 minutes... a minute and a half sooner. 15 pound bike wins.

Now here's where the fun begins. Look at the negative grades. As clydes, we get a big advantage over non-clydes when we're descending. Not nearly equal to the advantage that they get when climbing, but on a -3% descent, they actually go 16% slower than we do. This is why, in this years Tour de France, Thor Hushovd was able to win 2 mountain stages... they didn't end at a peak. Those stages ended at the foot of a mountain. There was no way he was going to win going up the hill, but when it came time to go down, he flew past everyone, despite weighing more than them.

Wind doesn't seem to make much of a difference if weight is the variable. In fact from the calculations the percentage difference actually goes down if there's more wind. I'm not sure how they figure that. I'm not certain that they factor in the fact that as a clyde, we simply have larger frames and therefore are bigger wind-catchers.

So basically, yes. Weight loss will help your speed. Since the speed loss from climbing is more than the speed gain from descending, your overall speed will go up. It's a matter of physics, really. But training will also help.