vader957

No, i was dropped by some superfit guy riding an MTB on flat, I was on my road bike. I thought that was bad but later I was destroyed by some girl riding a fixie. I had plenty on gears, she had only one and no brake (damn hipster). My confidence took a serious hit.

Notso_fastLane

For anything other than stop and go traffic like commuting, aerodynamics is going to matter a lot more than wieght.

That's why in a flat track race, a velomobile will always beat even a TT bike. An upright bike simply can not match the aerodynamic efficiency. If you're going so slow the rolling resistance is greater than the aerodynamic resistance, weight will matter more, but you're talking single digit speeds then.

movelo

Wow, I want one !

Just need to add 13.77 pounds to make it UCI legal.

fietsbob

Read any Newton ? its been out for a while , he lived (1643–1727), https://en.wikipedia.org/wiki/Newton%27s_laws_of_motion

bruce19

And, I think, accelerating up to speed.

jamesdak 

LOL, dammit!

livedarklions

It's a straw man because I don't believe anyone said that there was no difference required in effort, only that the difference was too small to matter.

We're quibbling over the meaning of the word "matter".

I can attest, however, that a 20 pound bicycle is easier to ride pretty much anywhere than a 55 pound bicycle. I rode the latter 90 miles in one day, once. Interesting experience.

livedarklions

I understand he used to come into your shop.

AlmostTrick

What? 3 posters literally answered "No" to the OP's question in the first 12 replies. I'm not even going to bother counting the rest.

Sure, but it's been fun. Thanks!

fietsbob

1) you get it moving , 2) you keep it moving , being level its less than (1)

and of course (# 3) you get it to stop... So is that the sum of 1 + 2 ? ... your question..


Sir Isaac Newton was dead 90 years before Karl Drais bone shaker Laufmaschine was Patented, 1818 ,
in Germany..











.....

livedarklions

So what was he like? Did he bring you candy?

Bandera

Apples, of course......

-Bandera

Edoubs

Wow

T Stew

Have you actually tried the boxcar or trailer example or just making a huge assumption? I have pedaled a 1,000+ lb railcar bike and can attest on the flats its was extremely easy to pedal. It was quite fun. I already new that weight made very little difference, but after pedaling 1,000 lbs it dawned on my just how insignificant weight can be except getting started and going up hills. Also the very heavy weight with much more momentum allowed for more coasting (along with an assumed lower rolling resistance), so I'd say the weight made a positive difference for me.


Exactly... weight matters to people in different ways. many non performance related like some people would refuse to ride a heavy bike for nothing other than elitism. Some would be happy that getting a heavier bike was cheaper and perhaps allowed them to spend money on other more needed things, so there is that. If you are lacking in upper body strength a heavy bike might be more difficult to wrangle onto a bike carrier. For performance, still depends what your goals are.. but as far as speed/effort on the flats its going to make about no practical difference, which seems what this thread is mostly geared to. Even if it did, does it really matter? Depends on your goals here... are you racing? Are you trying to not sweat in your clothes going to work? Are you training to be stronger? Usually athletes who are training to be stronger purposely exercise with more and more weight. No one brags about being able to bench press 10 less pounds today. I don't race competitively so even in the hills I don't mind a heavier bike, especially if it has other advantages (like racks and bags and may want to use).

For the heck of it I did just about what you are saying, and did not hardly notice the extra weight. Actually it was my first ever 100 miler a few years ago. I wanted to get a good shakedown ride with my touring bike I just added new racks and panniers and other gear too, and also wanted to simulate the extra weight I would be carrying fully loaded for touring since I have never cycled with any kind of heavy load other that a bottle of water and my emergency supplies in my saddlebag. So to my 20-some pound touring bike I added another 20-30 lbs in ballast weight, and completed my first 100 miler. It was pretty flat rail trail, and iirc I lost about 2-3 mph compared to my usual rides that are 20-30 miles. Not too shabby considering most of that loss was just the limits of my endurance having only done just a couple 50+ mile rides prior. Usually when people are talking about a 55 pound bike vs a 20 pound bike they are talking about completely different bikes of different build/quality/gearing/etc. But if you use the exact same bike, and just add some weight, the difference is very little and insignificant to most on flat courses with few stops. It can actually give you a mental boost when you pass someone with a multi-thousand dollar carbon fiber road bike on your 1988 steel Schwinn loaded with bags and gear because they think all that weight makes it so much harder and are shocked how easily you are passing them by. Actually they may be jealous of the 4 bottles of local wine you just bought at the farmers market in the middle of your tour through the Adirondack Mountains. Yes even in the hills on a long ride I believe I was much happier cycling after I added the weight of 4 bottles of wine.

In summary, extra weight is meaningless to me on a flat course, and even on a hilly course I don't mind it, its extra training load is all.

livedarklions

Yeah, what you're saying is probably true. I actually did this 90 mile ride on a Walmart Huffy cruiser which I had purchased on a whim when I decided to get back into biking. I thought I was just going to be riding 15 mile rides or so, and then suddenly found I was riding the beast further and further. I could actually do pretty well with it on the flats, often passing riders on good bikes who were about half my age, but on the hills, let's just say it got my legs into very good condition very fast. I've never actually ridden a bike that I'd consider good that weighed that much for any great distance, although I have run some pretty heavy grocery loads on my bikes. That weight affects the handling of the bike more than it does the amount of effort needed because of where the load sits--that change in center of gravity is noticeable, but easy to adapt to.

Daniel4

Weight, not so much. Mass is inertia. Mass matters only when you're accelerating or trying to maintain a constant velocity against friction.

Gresp15C

It occurs to me, figuring out if weight matters is something anybody can try at home. A gallon of milk is 8 pounds. A pint's a pound, the world 'round. Anything with a known weight can be attached to a bike.

xroadcharlie

If our bikes were equipped with steel wheels riding on a smooth steel surface, Like the train examples in other posts, Weight/mass would effect acceleration almost exclusively on a flat. And most of that can be recovered if we have the chance to coast, or at least by minimizing braking.

But the added weight will increase rolling resistance. This increase too can be minimized by maintaining the proper tire pressure for a 15% drop, thus tire deflection remains the same, And that might account for 70 - 85% of the rolling resistance change on pavement.

Happy Feet

The question being: "does weight really matter on flat roads?" one would assume all components of movement ie. starting, stopping and maintaining momentum.

As it is, I engage in what would probably be the perfect practical experiment every week at work to answer this question.

we use a wheelchair bicycle to take residents for rides either around our facility grounds or a couple of blocks further afield around an urban park. Both routes are basically flat.
Same bike, same rider (me) - the only variable is the passenger. Some are small and light, others are large and heavy.

There is a definite difference in effort needed depending on weight.

Lesbrill54

If you stuck a 1.5L Kia engine (me) in a Suburban, I think you'd find that weight matters even on a flat road. My new bike is 10lbs lighter than my old one-wahoo!
And is any road totally flat?
Even my new bike isn't as light as the OPs tho, it's a hybrid- Trek Fx 3 stagger( surely Trek didn't know that Fx means fracture? Especially terrible combined with Stagger! )

AlmostTrick

That 1.5 Kia motor is well over a hundred times more powerful than you. A typical pro cyclist will generate somewhere around 400 to 600 watts over a sustained period such as a time trial or climbing a mountain pass. At 746 watts per horsepower that's between roughly 0.5 and 0.8 horsepower. The rest of us produce even less. So yes, of course weight matters even on the flats.

Having said that, I agree that a pound or few in bike weight doesn't matter much, especially for heavier riders. For lightweight riders it matters a little more.

Lesbrill54

I'm a KIA 1.5 compared to a Chevy 454.

Korina

tl;dr. Don't care, I ride the bike(s) I like and don't worry about weight. Makes for a fun ride.

T Stew

Most vehicles consume very little horsepower once up to a steady speed. I think you'd find your Suburban quite capable of driving on the flat road with the Kia engine no problem. I read an article on this that used the Ford Flex iirc around 20 HP was all that was needed to maintain highway speed. I've also studied some kit car designs like one that used a Kubota 3 cylinder garden tractor motors. They were sluggish to accelerate but they could hit highway speeds. I got to see one in Cleveland, and Urba Centurion car with 18hp Kubota engine that didn't get the 128 claimed MPG but still close to 100. But people today want fast acceleration, an underpowed dog would not sell good no matter what mpg it got.

BengalCat

For road biking weight, (total weight bike and rider), is certainly important. Much more or less so depending upon the ride circumstance. That said, as important as weight is, it is nevertheless IMO the most overrated variable of riding and performance. Important for sure. Just not to the level people make it.

When you have people paying three times the price for carbon instead of plastic for things like bottle holders it is insane.