Bike Weight-Where is it really important and where not
 

OK...so I have a good CF bike...
I am not a pro racer.

How important is it to get a 200 gr saddle when my big butt is firmly attached to it when I ride.
Does the seat weight make a difference (including seat post weight). Does it matter if I carry my spare tube/equipment in the mack of my shirt or in a saddle bag that is attached to the bike.

If I used CG water bottle holders but use 22 ounce water bottles is that going to negate the benefit of the light cage.

I buy CF titanium spindled pedals and the lightest shoes.. but my big 13 feet are inside these super light shoes pushing on these superlight pedals.

I think you understand my question.
I know that revolving weight...tires/wheels/tubes make a difference.

BUT.. do these other really make a differenc

None of it makes a difference. Worry about saddle weight when there's no excess weight left on your body and you desperately need a 0.8% performance increase in the high mountains, i.e. never.

It all makes a difference. Grams here and there all add up. Take 3-4lbs off a bike and it will be measurably faster, particularly climbing, and accelerating.

It won't make as big of difference as many people would like to believe, but it does make a difference.

And "the don't worry about the bike's weight, until there's no excess weight on your body" is a false choice. No reason you can't put yourself and your bike on a diet.

I agree and disagree with Merlin. ;)

For example: You weigh 180 pounds, the bike 20. You're on a 7.5% grade, 5 miles long, at 250 watts. The climb will take you 40 minutes. If you reduce the bike's weight to 15 pounds, you'll save 30-60 seconds (or about 5 watts).

You have to decide, for yourself, if those margins matter to how and why you ride.

That said:
• I think it's pretty clear that the advantages of a lighter bike are exaggerated.
• You're going to pay a premium for those tiny weight losses.
• If you get dropped on a climb, no one is going to believe it's because your saddle weighs 300g instead of 200g.

In before "just take a dump before your ride," "empty one of your water bottles," and other such inanities.

Where lies the biggest weight-savings opportunity on a factory bike? Wheels?

As pointed out by merlin, a lighter bike (by 2,3 or 4 Ibs) is gonna make some difference, the real issue is whether that difference is cost-effective in terms of how much paid to rid your bike of the excess poundage.

Next to the frame itself, the wheels are the next "weight godzilla" on a factory bike.

QFT before you guys start going out and buying latex tubes.

The performance difference is pretty small. A 3lb weight difference in bikes, results in about .1mph speed difference on an 8% grade for an average size and strength rider.

You'll pay a lot of money to get that 3lb weight savings, and just riding around, the .1mph is hardly going to be noticeable.

But if your racing, closely matched with your competition and care about winning, that 3lbs is almost a minute over a 5 mile climb, which could be significant.

Thus, I totally agree it's a question of how much the small differences are worth to you.


Also, I'd say it's easier to make a case for a lighter bike based on more subjective grounds, like how it feels to ride, and bragging rights, than upon speed increases.

On my Roubaix, the most cost effective weight losses were the crankset and wheelset.

SRAM
S100 1025g w/ PowerSpline BB
Rival 830g w/ BB

I paid $125 at Competitive Cyclist for the Rival crankset. I saved 1.56grams/$

For wheels
Mavic CXP22 - 2200g
Custom H Plus Son/BHS - 1600g

I paid $380 for these wheels from a fellow BF member. I saved 1.58grams/$

I did not sell the spare parts though. The wheels would probably get a better return on the used market, but I'm building up a beater flatbar road bike and am using an old Nashbar frame with the wheels, crankset, and additional weightloss refugees (stem/handlebars) from my mountain bike.

Wheelsets aside, it makes a noticeable difference but in my book it's hardly worth the expense/hassle. Even knocking off a pound or two makes my bikes feel a tad more zippy, accelerate nicely, pulse up grades, etc., etc. Lightweight saddles? - I do like them, the bike doesn't labor when you swing it side to side. But it's hardly worth spending the money when losing 5-10lbs off the body will get in a better overall result. I'd take a lighter body/heavier bike anyday.

I think aerodynamics on a different set of wheels is more important than the weight savings of getting a new wheel. At least that's what I read. I always wonder how much faster I would be if I put on a more aero set of wheels.

As I posted recently, I just completed my rebuild of a repainted steel frame. Picking much the same parts (not all quite as light) as on my 13.8 CF bike and substituting 1/2 lb heavier carbon wheels, the total came in at 16.8 lb. Three pounds difference right on the money. Well I just rode it for the first time today. The performance difference was way too small for me to detect, but in handling the bike, picking it up, hanging it on the ceiling hook, push it forward to get started at a green light, etc. I can really feel the difference. This is all completely different than issues regarding my body weight. This is about wrestling the steel bike around. I love this bike, but I am a sucker for lighter, much lighter. "Riding" a lighter bike is a joy that can't be matched by much of anything else you can do to a bike (electronic shifting for example). Riding is in quotation marks because it means a lot of things, actual riding just being on of them. Everything is not just about racing results (casual or organized). There are other aesthetic aspects to bike riding, and a lighter machine maximizes many of them.

First wheels, then frame, then it doesn't matter anymore. Whatever you can afford.

I don't even carry water. I stop by people's houses along my route and drink out of their garden spigots. The weight savings on the bike is tremendous, and the amount of weight I've lost personally from running from being shot at is priceless.

Depending on how aero your current wheels are, and how fast your ride, about .1-.2mph

I can only imagine the looks I'll get if I try delivering that excuse next time I'm dropped on a climb.
Maybe I'll try it tomorrow.;)

that's it, that's the ticket AND you save having to wash bottles

In the grand scheme of things for us average Joe's who cycle for exercise and with other like minded people..............fit is the most important thing and mainly the saddle. In all reality most road bikes (modern) that is are roughly the same weight to a lay person if lifted up by one arm. SO that weight means nothing. Now if your competing and your foes are all roughly same weight as you and experience and ability shaving weight (grams) even ounces could mean beating them at the finish by hundreds of a second or so and then it means all!

But for a majority of us > I would say 99% here...............just ride and enjoy! There are always those you see while riding that have the Armstrong complex and think they are pro's when they are actually just Joe's! I laugh at them when I pass them and it makes my day...............

I figure losing weight off the bike comes in at around $1000/lb. The ~$1.58/g mentioned upthread works out to $717/lb. I think about that when I get on the scale in the morning. So far this year, I've saved the cost of a new Calfee tandem. Of course you can do both things at once, but still . . .

I don't think the location of the saved weight makes much difference, though saving it off your body makes more difference than saving it off your bike. Lots easier to climb out of the saddle standing if you're light. Everyone knows it's better to carry water in bottles than in a Camelbak as far as energy cost goes. Weight makes a much larger difference if you're racing and already climbing near the front. Doesn't take many seconds to put you from there onto the leader's wheel on a long climb. But for a more recreational cyclist, it's just seconds/lb., i.e. like $100/second/lb.

It's fun to play with calculators like this one:
http://www.hembrow.eu/personal/kreuzotter/espeed.htm
to answer these questions:

Seriously, that's it? I was hoping for 10x that. Screw that, I'm not getting new carbon wheels, no matter how much they are advertised on this website sidebar.

I might be slightly pessimistic there, but probably not far off in the real world. Take Zipp 404's. Zipp claims they save 80 seconds in a 40K TT at 30mph. That works out to .8mph

Now put some real world assumptions in there. You're not typically going to be crusining at 30 mph. The mph difference becomes much smaller at say 20 mph (although the elapsed time difference can get bigger). Next, I'm pretty sure Zipp does that calculation at optimal wind angles to make their point. Real world, varying wind angles, my bet is the speed advantage narrows again, and finally I'd be willing to bet they're picking a pretty un aero wheel to compare them to.
(they say a top selling aluminum race wheel, which I wouldn't doubt with be a Kysirium which has the drag of a parachute).

Distill all that down, and we're talking a real world difference not of miles per hour, but tenths of miles per hour.

Owning 3 different sets of Zipp's, I 'm certain any advantage is well below 1mph.

There's really about 2 categories of weight all of which have different impacts.

1) Rotating mass (removing this improves acceleration more greatly)
1a) Rim/tire weight (highest moment of inertia)
1b) Hub/crank/spoke weight (lower moment of inertia)

2) Fixed mass
Removing weight higher up feel lower the CQ and improve handling all else being equal.The rider is assumed to have a high CQ.

of course, there is having to carry bikes up stairs and stuff to, that makes a diff if a bike is heavy.




and this is a case where losing 5 pounds might make a diff.
http://24.media.tumblr.com/7e98264f4...du4o1_1280.jpg

Men, I can hear that rig snickering "does he really need to eat another bowl of ice cream?":lol:

Seriously, weight off a bike is going to go unseen. Lose weight off your body by pushing yourself and getting stronger while eating right and you will see bigger gains no bike component can do for you!

You are completely right, but missing the point. First of all, the two areas of weight reduction are not mutually exclusive. You can lose body weight and remove bike weight too, and get even better results. Or you can do the one you want to do. But more importantly, lighter bikes are simply more fun to ride, to maintain, to own. It is not just about speed and competitive results. It is about pure pleasure. Get on a 12-13 lb bike if you can find one and give it a try. There is nothing like it.

I have two bikes. My beater is a 1998 Cannondale, comes in at about 23 pounds with its lights attached. The other is my 2004 Calfee which comes in at 17.5 pounds.

I still ride both on my commute, which is 18 miles each way. The time difference between the two bikes is, at most, one minute. The Cannondale feels like a tank though, and I always think I'm crawling... until I pull into the office and realize that it took essentially the exact same amount of time.

Now, if you're racing, that one minute over an hour time gap would be huge...

Wh..Where are his calves? How does he pedal? or walk?

When I delivered in a hilly area, and spent 4-8 hours a day on a 26 pound steel bike, and few days on a 17 pound bike. It felt like a huge difference. over the course of a day, and any day i dont have to carry my camera bag, I feel faster.