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How much does frame weight REALLY matter?(15 posts)

How much does frame weight REALLY matter?David
Oct 29, 2001 1:16 PM
I know that the most important place to loose weight is the wheels. Assuming I have light wheels, does frame weight matter all that much? The difference between a $2600 titanium frame and a $1200 steel frame is about 3/4 lbs. (and $1400). Isn't that about what a full water bottle weighs? Can you tell the difference in performance on your bike when your water bottles are empty? I swear I can't.
You can calculate itDog
Oct 29, 2001 1:25 PM
Go to http://www.analyticcycling.com and plug in the numbers for weight up a hill (and down the hill, too, if you don't brake!). One pound is actually a fairly small difference riding up even a huge hill.

Interestingly, weight matters more to those with less power than to those with lots. Climbing is about the power to weight ratio, and the lower the power, the more significant weight is.

Nonetheless, gotta figure what the trade off for the weight savings is: flex, reliability, cost. Might save money on the frame and put the money in wheels, for example.

Doug
re:Softrider
Oct 29, 2001 1:34 PM
To some people it matters quite a bit, i.e for the elite pro racers 3/4 of a pound is significant.

The question is, does it make that big of a difference to the other 99.99% of bicycle riders in the world. My guess would be not really.

On the other hand, there is nothing wrong with owning top of the line equipment either. IT CAN'T HURT!!!!!
I've always thought we overemphasized frame weightcory
Oct 29, 2001 2:02 PM
Even in the best condition of my life, it would have been easier and cheaper for me to take a few pounds off me than off the bike. I've used that water bottle example many times--people spend a lot of money to reduce the weight of the bike by that of a few swallows of water, an energy bar or that extra serving of hash browns they had for breakfast. My Atlantis actually weighs a little more than the bike it replaced, but it fits so much better and is so pleasant to ride that it feels lighter.
Wheel weight is more noticeable. My Velocity rims weigh about 100g apiece more than the old wheels, and I do notice that when I'm trying to accelerate. As far as total weight goes, though, I not only can't feel a water bottle, I can't feel the Blackburn rack and the Carradice bag, either.
hmmm...CT1
Oct 29, 2001 3:02 PM
David

I noticed a 'nice' difference when I went from a 17.5# steel framed bike (MXL) to my 16# LOOK (carbon) and 16# Giant (Al) framed bikes. It's very hard to quantify the difference but the two lighter bikes feel somewhat quicker when hammering up hills. If you live in a very hilly area a pound is measurable..... more so on the wheels than frame but nonetheless still noticeable. However, I suspect I'd have a hard time in a double blind test if I was comparing less than ¾ pound.

Also, one pound on the bike (especially the wheels) is more significant than one pound on the body.

I think the previous comment regarding the relative importance of bike weight in relationship with the riders weight/strengh is VERY important to keep in mind.

YMMV
JohnG
hmmm...nigel
Oct 29, 2001 3:10 PM
I'm sure that your superlight carbon and aluminum bikes feel lighter than your still-light-but-heavier-than-these steel bike. The greater difference could be in the stiffness/efficiency and/or geometry as well. Is your Giant a TCR (compact geometry)? If so, this could make a noticable difference when climbing and sprinting, since these frames can transfer your power better to the wheels.

I'm a TCR man myself, and I feel a huge difference in the tighter, stiffer build.

Light bikes sure are NICE, though, eh?

Nige
here's a pic ... TCR :-)CT1
Oct 29, 2001 6:40 PM
Yup, it's a TCR.

I built the bike with Record 10 and a fairly light build kit. I've got a little over 2K miles on it in two months. The most surprising thing about the bike is the nice smooth ride quality. I can pump my skinny-assed front Veloflex Pave up to 120# and ride for 130 miles without any problema at all. Very surprising.

Getting back to the original point: My MXL had a VERY stiff BB ..... absolutely as stiff as the TCR so I don't think the felt climbing difference was that. ??? Maybe I'm FOS, but I think it's the 1.5# difference.

ride on fellow TCR man
JohnG
Question on the Veloflex Paves....tirider
Oct 29, 2001 8:40 PM
... how do you like them? I'm considering trying them. I assume that's their all around tire as opposed to their Records which if I remember are a little lighter. I use Conti GP 3000s... anyone use both and have opinions?
Question on the Veloflex Paves....CT1
Oct 29, 2001 9:49 PM
I actually rather like them. However, they are only rated to 120 PSI so keep that in mind if you are heavy and/or like ultra high pressure tires. If you need more pressure the Vred tri-comps are excellent!

I'm getting about 1500 miles on the rear before the tread is REALLY flat spotted the tire starts looking sketchy. No significant cut problem. They're reasonably sticky and haven't had any problem holding a hard turn.

The road 'feel' is good but I haven't tried a lot of different tires. Definately smoother than the Conti GP's.

Oh, the Pave's I've gotten all weigh 175 gms. They are a little on the small size..... I.e. a small 22. Also have a funky smell when new, which I sort of like ;-)

ride on
JohnG
I'm with youfiltersweep
Oct 29, 2001 3:13 PM
It's pretty flat around here, and I know I don't have the lightest bike on the road. I'm out for fitness, and I figure a heavier bike saves me thousands of dollars and gives be a better workout. The only places I see weight mattering is hills and acceleration- if you are not racing, but holding a steady speed for a long time, what's the difference between a pound or three- and again, weight involves the entire package (rider included). How much does a full bladder weigh? Of that food you ate three days ago? I'd guess more riders could benefit more from improving form and aerodynamics than from a lighter bike!
re: How much does frame weight REALLY matter?Dutchy
Oct 29, 2001 6:05 PM
I would think that a lighter frame would certainly feel easier to ride,
but would it help you ride faster?
Considering most frames these days are fairly light anyhow there is a smaller difference between
a "heavier" & "light" frame then there used to be.
The difference would be more physchological then anything.
Your're own body weight is the biggest hurdle you have to overcome.

eg. I used to ride a very hilly 28ml loop in 96' when I weighed 128lbs and was 26 yrs old.
My best time was ~1hr32min. Now 5 years later after having my final growth spurt I weigh
150lbs and my best time in years was ~1hr38min. So the bike weight has little
to do with my performance, my speed is slower due to the extra 22lbs I now have to carry up all those hills.

Unlike Lance who lost weight I have gained weight :-)

CHEERS.
Is it only the weight?Kerry Irons
Oct 29, 2001 6:13 PM
If you are looking at 1#, that a 265 feet difference in a one hour climb at 6%. Enough to win a stage in the TdF, but probably not so significant to you. When climbing, weight is weight, whether it comes off your wheels, your frame, your seat post, or your gut. However, you're assuming that the only difference between these two frames is the weight. It's just possible that the more expensive bike has some other advantages than just a weight savings.
where's the weight ????CT1
Oct 29, 2001 6:58 PM
Ahem...... It most certainly DOES matter where the weight is located.

Most important: wheels .... rims and tires MOST important
less important: bike
least important: rider

If you gave me one pound of "dead" weight I'd MUCH rather have it strapped to my body than on the bike. This has to do with the accelerations (and subsequent forces) the particular weight "sees" when you are riding a bike.

JohnG
ConfusionKerry Irons
Oct 30, 2001 6:03 PM
The only time wheel weight, and specifically rim/tire weight, is any different than any other weight, is when you are accelerating. In that case, it takes 2X the energy compared to non-rotating weight, and this added kinetic energy requirement is tiny compared to the aerodynamic drag or climbing power needed. If you are not accelerating, then it makes no difference where the weight is. If you are climbing at a steady speed, the calculation is quite simple: mass times distance climbed per minute. It takes no more energy to lift a spinning wheel than a non-spinning wheel, or the same weight in water bottles or around your gut. The only "real world" case where lighter wheels are "different" than a lighter frame or lighter body is in a criterium, where you are constantly braking for the corners and then accelerating out. Otherwise, the added energy it takes to spin up a heavier wheel is returned when you slow down (without brakes). It's all in the physics book.
re: How much does frame weight REALLY matter?Peter E
Oct 30, 2001 4:26 AM
Even if the puond of your bike wheels or whatever doesn't really make thata big difference in how easy it is riding. Isn't the pshycological difference of you THINKING it is easier to go fast just as important to help you really do it