Does bike weight really matter?

[ultrazenith]

Hi all,

Having at one time (in the 90s) been an aspiring weight weenie, I have experienced the obsession with cutting down on my bike's weight as far as my budget allowed. At the time, light weight at all costs seemed to be the prevailing zeitgeist in the XC mountain biking scene, and I barely stopped to wonder what difference a saving of 1 lb would make to how fast I could ride the bike.

Consider a bike+rider combo weighing in at 80kg (70 kg rider, 10 kg bike). Saving 1 kg off the bike would reduce the total weight to 79 kg, a decrease of about 1 %. This would result in an increase in uphill speed of ~1% for a given power output from the rider, shaving about 30 seconds per hour.

Does this match others' experiences of the effect bike lightness?

 

[ellist]

On the road not as much. Bouncing over stuff cross country I would say yes. A lighter bike interacts better. Mainly nice wheels matter most and tyres. From what I have read a weenie Tyre will have you say on a verge more often.

 

[jimo746]

Lighter = better in most cases.

In the early/mid 90's things got silly light, manufacturers were pushing the limits (and sometimes exceeding them) of how light frames & components could get.
I think that as the popular riding styles changed (think of modern freeride, all-mountain, bike park stuff) then strength took over from lightness.
Nowadays lightweight is high up on the agenda again, partly due to carbon and composite technologies, making things strong and also lighter (and expensive).

Any weight shaved off your bike is a good thing, it's just whether it is cost effective to do it, besides, there are always those pub bragging rights over who has the lightest/blingest/costliest bike :roll:

imo you're better off doing more riding than worrying too much about bike weight, rider fitness generally is a much bigger factor than a couple of pounds difference in the bikes weight.

 

[Neil]

Thing is, a lot bang on about how good a light bike feels - and no doubt that's true, up to the point it doesn't compromise it's robustness. But here's the thing - plenty of people carry sufficiently extra bodyweight they'd probably find more cost-effective to shed some of.

And often, some reduction in bodyweight is accompanied by improved fitness - so double whammy.

I think most enthusiasts want their bike to be as light as it can reasonably be - but how many could easily spare to lose a few pounds themselves? If it really was so important to me, that my bike be as light as reasonably possible, I'd exercise the same scrutiny in my bodyweight - else it's just some artifact, really.

 

[ellist]

I would agree. A vehicle needs a good engine. That said as a cuddly fella riding a light Kona instead of a 20kg full sus jelly I am a better rider and have more fun. I agree though I could always lose a few stone (hoping the bike helps) or a water bottle or two

 

[widowmaker]

I must admit that since riding my Roadbike I have been weighing component including MTB.

The weight of a water bottle 750ml, plus the cage and screw weighs nearly 1kg :shock:

And a seatpost for my Saracen was nearly 1/2 a kg :shock:

 

[jimo746]

maybe riding a 20kg downhill rig is actually better for you? your fitness should soon improve!

 

[dirttorpedo]

With respect to retrobiking, I think weight is important - particularly if you want to go fast. My expereience is that weight savings in rotating parts pays the biggest dividend from a pure go fast perspective. Light weight can be important as well if you need to use a lot of body english to get your bike over obstacles - bunny hopping and whatnot. That being said I recall reading some reviews in the early 90's of sub 19 lb xc bikes that suggested you could get too light and that those bikes were so light that they didn't behave well on the trail. Of course that was before full suspension and they were finding that those light bikes bounced around a lot. My gut feeling was that 21/20 lbs was the sweet spot for a fully rigid retrobike.

Being poor, I've never been able to test this theory out personally.

 

[unclechet]

Train heavy and race light. And I agree most people (myself included) could probably shed more weight off their body cheaper than they could ever shed off their bike. But a light bike (wheels/tires especially) will accelerate and perform better for everybody regardless of their body weight. And it's fun to have trick parts.

 

[Rahbari]

The accelertion of my (period correct) 9,2 kg Xizang with stiff Syncros steel cranks and a light Tune wheelset is simply overwhelming. Even though I weigh 86kg.