Weight weenie question...when do you notice a difference?
 

How much weight do you need to remove from the bike to actually notice a difference?

I have never ridden a 14lb bike, but I'm pretty sure I would notice a significant difference from my current 24lb bike, but would a 20lb bike be a noticable difference? At what point would someone notice a loss in bike weight?

It's all relative. Some will say they notice just about every difference. others will say you never notice a difference. I matters a lot what KIND of weight you are removing as well. Depending on the change you may actually be changing materials that result in a change in how the bike handles and feels that aren't necessarily weight related.

How much hill climbing do you do? Weight is typically more important to someone in San Francisco than in Tampa. Of course it also has an affect on accelerating and decelerating, but this is less profound, and it's also something a lot of riders do less of, vs climbing. Also, where the weight is can make a difference; my commuter bike has panniers, which means I can bring books and other heavy things with me, but they mount high on my cargo rack, and raise my center of gravity, which makes the bike tipsy.

My road bike is about 19 pounds and my cross bike/commuter is about 29 without the panniers, or maybe 40 pounds when it's loaded up. There's a profound difference, like night and day.

^What he said.

For example, removing weight from the rim will be noticeable, while removing weight from the hub won't be as noticeable.

Removing weight from the seat post/saddle will be noticeable (on out of saddle efforts), while removing weight from your stem won't be as noticeable.

Figure the percentage change of the total bike and rider. If the total is 200, then 2 lbs is 1 percent and it's only helpful when climbing. After riding long mountain climbs for the last 7 years, I don't think that anyone can really feel a 1 percent change. If I'm going up a tough climb a 12mph, 1 percent it .12mph. There's a lot of imagination involved in feeling those small changes.

I notice it when I pick the bike up to go outside and ride it.

you are too smart to fall for the linear speed vs. gravity thing

When I first got my 24lb road bike my jaw was on the floor. I hit the pedal and the thing FLEW, also going slightly uphill didn't feel like anything! I couldn't tell the difference.

14 pound bike? I hope I die before I ride one, could never afford it let alone maintain it. Ignorance is bliss.

I just did a calculation for a Whiteface ascent:

250w

150 lb rider, 20 lb bike = 60.63 minutes
150 lb rider, 18.3 lb bike = 60.1 minutes

a 1% reduction in weight was good for 30 seconds.

their is a reason alot of people say to change your saddle first then your wheelset.
saddle will make you comfortable for long rides
and the wheels are rotational weight. I could feel a huge difference between my 2375g wheelset and my 1975g wheelset (these weights included wheels, tires, tubes, cassette, and skewers) and that is only a 0.88lb. difference but that is ALSO rotational weight reduction.....

I take it you don't think 1.7 lbs is worth the $2,400 difference between the two bikes involved.

In other news, how much do two full water bottles weigh?

...or rather less than 1% of time. Weight matters, of course, but let's face it, working on the rider - in terms of both weight and fitness - is for most of us going to make far more difference than spending money on the bike. When I can put out 5w/kg, then I'll start worrying about the fact that my bike weighs 8kg.

Which will be never, btw.

you dont carry bottles on the whiteface time trial unless you want to be slow.

or you could race the hill against a bunch of guys in your power/weight class and get beat because they bought lighter bikes. either way, physics are physics.

there's no point in even asking a question like the one in this thread unless you plan to compete. if you are just riding around, then who gives a flying frack.

It's close enough for a swag. Go to a website like analytic cycling. Put in a 4% climb for a total rider and bike weight of 100Kg, then 99Kg. The difference in speed is a little less than 1%. Put in 90Kg, a reduction of 10% and you get an 8% increase in speed. Close enough for me.

http://www.analyticcycling.com/ForcesSpeed_Page.html

yeah it's close for a 1% difference, but it's not linear. you see that when you make greater changes in weight.

Obviously in a race that is a lot, but even not in a race that is long enough to take a drink, catch your breath, and be whistling when your riding buddies reach the top.
Now of course your could perhaps lose a little more bike weight, have a slightly better power to mass ratio, and dig a little deeper for a few more watts and you just destroyed your buddies up the climb.

This.

I didn't notice a difference going from a 20lb bike to a 16 3/4 lb bike. Then I changed the wheels and lost 3/4 a pound. That I noticed.

I notice it a lot in how the bike handles. I feel like and know that I can throw a lighter bike around a bit more for faster handling. I'm seeing this firsthand with my cyclocross bike. I thought I wanted a heavier bike that could take abuse, but as I race it more and more, I know it's not the right bike for me - mostly due to it's weight via handling. I'd feel a lot more comfortable on a lighter bike that I could muscle around a bit more.
Same with my road bikes, for commuting, a heavy bike is fine and preferred, but I like a lighter bike for more aggressive riding.

+1 It is all psychological unless you are 160 pounds I wouldn't worry about an ultra light bike.

It's a matter of degree.

My 32 lb touring bike felt a lot lighter AND much easier to climb hills with than my 32 lb touring bike loaded down with another 35 lbs of gear. And my first road bike, at 24 lbs, felt noticeably lighter and easier to climb with than the touring bike. When I first built up my current road bike, it was about 18.5 lbs. It definitely felt a lot lighter, but climbing felt pretty much the same. It's easier to fling the bike around when out of the saddle, which is what's really noticeable about the weight of a bike when actually climbing.

I think the major difference in feel between all of these bikes has more to do with geometry and fit than weight. A touring bike will be biased toward comfort; a road bike toward power. Other bikes will generally fall in a range between these extremes, and the effect of weight depends upon your goals. So, assume the same geometry, for the sake of argument: if you're touring or just riding around, then a lighter bike is noticeably easier to climb with, because you are typically seeking ways to reduce your effort without just going really slow. You're not going to going flat-out, because you want to enjoy the scenery, or because you don't want to wear yourself out completely from riding all day every day. Pushing more weight up hill after hill, day after day, is noticeably tougher than pushing less weight.

If you're racing or otherwise looking to get the best possible climbing performance, then the point about effort is academic. There is no difference in effort, because you're working as hard as possible, period. The difference under these circumstances is speed. You're going to climb faster at max effort on a lighter bike, period. When I'm going hard on my nice bike, it doesn't feel different than my old heavy bike. I still want to puke. I just get to the top a bit faster.

Keep in mind that these differences are a matter of perspective, not physics. The physics are the same. Same effort + less weight = more speed. Same speed + less weight = less effort. Same terms, just arranged differently.

how do you know this is due to the weight and not something like the wheelbase, rake/trail or headtube geometry?

qft.

Wheel weight I notice. I went from a 15.5 lbs bike to a 17 lbs bike that has lighter wheels. The 17 lbs bike is great. I won't say it's heavier or lighter feeling; the wheels were all of 150-200 grams lighter. But going from wheels literally 2 lbs heavier... huge difference.

There seems to be cusps of "perceived weight". Just roughly I'd set the divisions at 28 lbs, 25 lbs, 21 lbs, 19 lbs, 16 lbs, and about 13-14 lbs. The first few weights pertain mainly to mountain bikes. I guess in the same ranges all the time "Oh it's about 16 lbs" when it's 15 or 17 lbs. The really light ones are 12-13 lbs, those astonish me.

As far as weight goes... except when going to tubular tires, light bikes can be used every day. If you trade time for money, you can build a very light bike for a minimal amount of money. It may take a couple years, but it's possible. A young racer, maybe 22-23 years old, had a 12 lbs bike that he'd built up for about $2000 (2007?). With clinchers it'd be 13+ lbs, but still very light.