donheff

I see a lot of people going to extremes to shave a few ounces off their bike weight and always wondered if it was worthwhile, even for amateur racers. I know the exhilarating feeling a lightweight, carbon fiber speed machine provides vs a far heavier machine but I am curious if technically inclined members know if there are real physical reasons why shaving a couple of pounds of the machine would make a bigger difference than shaving the same amount of body weight. Or, even more pertinent, would knocking a pound or so off the bike beat knocking a couple of pounds off your gut? It would certainly be cheaper to lose a couple of pounds by saving on food than to trim off a pound on an already expensive bike.

I know the simplistic science would say weight is weight, but I also know how much quicker I feel sprinting up a hill on a lighter bike. So, given a similar aerodynamic profile and drive train, would something like materials (e.g. steel vs carbon) make more of a difference for speed and feel than losing an equivalent or great amount of body weight?

europa

Don't get rid of that big gut. It's an aerobulge that allows the air to flow smoothly and evenly around your body dramatically improving your aerodynamics

Of course, that might all be horse cobblers

Healthwise, you're obviously better off without excess fat however, don't drive yourself insane attempting to achieve it, mental issues are every bit as toxic as physical ones.

As for the bike, buy the bike that suits you. I like traditional bikes and steel frames. I'd really like to have that in a bike as light as my son's carbon fibre racer, but it's not going to happen so I just accept it and make jokes about battle wagons and comment that any car that pulls out in front of me is going to be cut in half before my bike even notices.

Garfield Cat

Body weight is a variable and bike weight is not as much.

Our intake of different kinds of food and then our calorie output are in constant change.

Then we have the age thing to deal with.

mr_bill

First, in general, it's not either/or.

Second a 1 pound or 500 gram difference isn't that much noticeable for an amateur. (In fact, your daily weight probably varies that much.)

But a 22 pound or 10 kilogram difference is very much noticeable. And as much as I'd rather ride a DIVVY than ride nothing, or a Dutch Gazelle than ride nothing, I'd rather ride my bike instead.

(And practically speaking, I can't lose 22 pounds or 10 kilograms.)


Finally, there is *ONE* place that you'll notice much more of a difference of 1 pound or 500 grams on the bike than on you, and that's one pound on the bike rims/tires - if you are accelerating. Not without tradeoffs though at the limit.

-mr. bill

Barrettscv 

My philosophy is that personal weight loss, training, gearing and tires matter more than bike weight. Once I've reached my ideal weight and have trained to maximize performance, I'll begin to think about an ultra light bike.

I've lost 25 lbs in the last year. My bikes weight between 19 and 27lbs. My unscientific impression is that a lighter bike accelerates faster than a heavier bike on flat routes. This is important in a fast group ride, since most groups tend to surge and coast. Frequent accelerations on a heavy bike can demand the rider to use up energy faster than if the rider has a lighter bike.

A heavier rider is going to be able to ride a flat route at a steady speed using approximately the same amount of energy as a lighter rider. Speed at a steady velocity is dependent on aerodynamics and mechanical friction, not weight. However, the heavier rider will need considerably more power and energy to climb and personal weight loss is critical to improving climbing pace.

Bike weight on climbs is also important, but it's not the most important factor. Body weight matters more. Also gearing and pedaling form & technique are more important the bike weight while climbing. Spending thousands of dollars to reduce bike weight from 19 lbs to 17 lbs is not a priority for me.

.

Machka 

I was slender most of my life ... borderline underweight. So the option of losing more weight would have put me into unhealthy territory.

Somewhat recently, I slowly put on weight and hit my highest weight ever (just within the "overweight" category) at the end of 2014. So I lost the weight in 2015.

Yep ... there's a difference between the lighter me and the heavier me. The lighter I am, the easier it is to get up hills.

mpath

While it might be cheaper, it isn't necessarily easier.

And in the 50+ category - with the idea being we've peaked in our careers, empty nesters, or retired/nearly retired - we have more disposable income (at least that's the hope/expectation) to buy weight, ahem - buy less weight - on the bike, rather than lose body weight.*

(*Not counting cyclists who cannot lose any more weight, ie. they're already at their ideal weight or even underweight.)

donheff

What seems strange to me is that when I first tried a good, lightweight bike about ten years ago, my immediate reaction was WOW, acceleration and climbs felt like a comparative breeze. I bought a ~$2000 range bike and never looked back. But when I dropped from 195 to 162 for years ago, meh, not much difference. And it wasn't because of muscle loss - I was careful to add in substantial weights to keep that up. That's not saying that I don't appreciate the weight loss - I look better and my numbers are significantly better. I am sure that I am healthier for doing it. But I haven't noticed a noticeable improvement in riding - or at least none that would subjectively compare to the initial significant bike change. So my takeaway was that a significantly better bike will make a big difference in feel. But expensive tweeks to upgrades shave off those last couple of pounds? Can there be anything to it?

Barrettscv 

I participated in the Illinois Senior Olympics this year. Several participants bring $6000 bikes with $2500 aftermarket wheelsets and aerodynamic race helmets and suits. These individuals also train with precision and dedication. How fast they are depends on a multitude of factors. Diet, motivation, conditions can reduce or increase performance significantly. When all the factors come together, fast gear and a prepared competitor can be unbeatable. However, each individual factor only plays a minor role.

I enjoy an upgraded bike as much as any cyclist. However, as Eddy Merckx said: (If you want to ride faster) "Don't buy upgrades, ride up grades".

brianmcg123

12lbs = 1mph.

For every 12 pounds you lose, you gain 1mph at the same power output.

Bandera

The belief that exotic hardware "improves" performance in cycling is a marketing mind-set divorced from the boring reality that effective cycling takes seat time and work.

More $ spent on ceramic bearings, aero-doodads & nano-tech framesets is an easy credit card swipe away while putting in the base miles to develop endurance, dragging up the hills to work on power and putting the watts out for the city limits sign world championships is not.

A good quality basic machine properly fitted and chosen for the type of riding one does on the local terrain ridden regularly is all that is required to enjoy the activity and improve personal fitness. Getting one's weight down requires lifestyle changes, combined w/ regular cycling an improved watts per kilogram results. Spending $ on lightweight stuff does nothing for fitness. A fit/lighter you will climb faster/easier than the same you with CF-doodads, less seat time and a bit of a paunch.

That being said many folk love cycling hardware in and of itself.
An exhaustive search for that C&V grail bike, having a custom frame made exactly to spec or getting that Pinnalized-Specerello Team Shy replica is indeed gratifying and one has something to display to the cognoscenti other than a pile of worn out tires, chains and cassettes.

Not confusing hardware with the fit, fitness and technique that makes for effective cycling is not what marketing-speak is designed to do.

-Bandera

rumrunn6

something in my rear trunk is weighing me down, gotta lighten that. too many co2 cartidges? ditch the pump since I carry co2? just added a chain repair kit, good grief

John E

If you stand on the cranks, there is also the issue of static vs. dynamic load, which includes not just bike weight vs. body weight, but also the choice between a backpack and a rear rack or basket when carrying cargo. I do note that my 10kg Bianchi (not light by today's standards, but pretty decent in its day) is more fun to ride than any of my other bikes, but this might also be a matter of frame geometry.

prathmann

If I have to carry the bike up to a 4th floor apartment I'd rather be a 170 lb man carrying a 15 lb bike than a 160 lb man carrying a 25 lb bike.

dabac

Being an all-year rider in a place where winter means snow and ice, My main commuter sees some fairly radical changes in tire weight.
Looking at the clock, nearly tripling the tire weight cost me about 10% in speed.
Going by feel, I'd have guessed it cost 25% or more.
Still, give me someone to chase, and I can make a winter commute in the same time as an average summer commute.
My theory:
- a lighter bike responds faster to rider input.
It becomes more fun to ride.
So you try harder.
And by that, become faster.
How much faster it actually is - for a given input - isn't proportional to how much faster it feels.
It's that tricky, non-linear, illogical lump of organic matter on top of the bike that's messing with the equations.

Iride01 

I went from a 44 pound Schwinn Varsity to a 24 pound Raleigh Competition. While I noticed the difference in acceleration and hill climbing ability I didn't really see a big difference in the times it took me to do the same routes. Even my 100 mile rides up the Natchez Trace and back were not that much different. The bikes had pretty much the same high and low speed gear ratio's though the Varsity only had a five speed rear and the Raleigh I put a seven speed rear on it.

I'd still go for the lighter bike almost any day if I had to chose. The only other thing that might sway me in another direction is that for a particular ride, you might have to chose your heavier bike if it has better gear ratios for climbing steep hills.

Other than that, I think this is the post that puts everything into perspective....

bbbean 

Apples and oranges.

Weight on the rider: The more you can increase your watts to kg ratio, the better. Since more of us are over weight than underweight, that does mean you'll likely ride further, faster, and easier if you lose weight.

Weight on the bike: Unrelated to weight on the rider. As a general rule, lighter bikes will be faster than heavier. We can argue about how much faster or what that is worth, but it holds up as a general principle. <intentionally simplified>

Consider - You want to ride today - right now. There is nothing you can do to make yourself lighter. But if you have a choice between two bikes, you will be faster on the lighter bike, all things being equal.

The question "should I lose weight off my gut or off my bike" is nonsensical. If you want to go fast, you should do both. They aren't mutually exclusive. This is akin to "should I buy a race bike or train harder?" Again, you should do both if you want to go faster.

BB

wphamilton

No, it doesn't make a difference in your performance whether the pound is off the bike or off your body. Any differences there might be, due to physiology, inertia of the frame when leaning and so on, are going to be too insignificant to matter more than psychologically. The 19 pound bike with a 161 pound rider will not accelerate faster than the 20 pound bike with a 160 pound rider. Other things equal, they will handle the same.

In the more general sense, I'd vastly prefer to shed the pounds off my body rather than the bike, because it will mean I'm in better condition, it will improve my metabolic efficiency, and I'd say it's just all-around more rewarding. I got a little sloppy this winter and spring but I've lost about 10 pounds since then and have maybe 5 more. After that's done I might think about lightening my bikes, but I probably won't feel much urgency in it because I know it won't make me any faster.

cycloaptrgangr

Add .5 pounds to each wheel (heavier rim, tubes, tires, or all three) of that 19 pound bike to make it a 20 pound bike.

Your comment is simplistic.

TGT1

that's really the illusion brought on by the human body's exquisite proprioception abilities.

After the first 30 ft or so of accelerating from a standstill it really doesn't make any measurable difference.

Crank57

I'd love to be either a 160lb or a 170lb man carrying anything up 4 flights of stairs since I'm 220lb.

Biker395 

On first principles, it doesn't matter if the weight is on you or on your bike. But if you consider that we are not simple point masses, I'm not so sure.

I've noticed that weight (whether it is the rider or the bike) seems to make more of a difference than it should. I've often wondered how the analysis works out if you did a 6DOF simulation of a rider.

It takes a lot of energy to overcome inertia, and that happens when masses are accelerated in any direction. So if you are standing on the pedals in a sprint and swinging the bike left and right, it takes more energy to do that with a heavier bike than it does a light one. The same is true for the person riding it of course.

None of us pedal in a way that puts a constant force on the drivetrain. Since force is being applied in dull pulses, we are in fact, accelerating and decelerating a small amount as we ride. I'm sure it is a very small amount, but it is happening all the time, and the amount of extra energy expended for each acceleration and deceleration would integrate over time to a significant amount.

As for whether it is better to have the weight on you or on the bike? No question. Better to have it on the bike. That way, you feel better, wear your joints out less, and look better besides.

wphamilton

It was a carefully considered comment. The half pound on each wheel makes very little difference compared to a pound on the frame - the main effect you'll see is a very small change in acceleration, which is counterbalanced by the rotational inertia unless you're constantly on your brakes after small surges.

Riding uphill, the wheel weight means the same as frame weight because the rotational speed of the wheel is mostly constant in the climb. Downhill, it can help you a tiny bit, beyond the amount of extra static weight.

@Biker395 don't forget the flywheel effect in your energy calculation.

joesch

Eddy is ofcourse right on !
How about a contrarian suggestion, rather than spend lots of $$$ to shave off oz's, spend it on a nice used training bike that is ofcourse heavier then when you ride your racing bike, you will really fly

BigAura

You need a 15 pound bike AND look like this: