CycleDeac

... does a bike that weighs (say 23lbs) compare to a bike that weighs 15-17lbs. Lets say you're interested in racing Cat 5 and you have an average fitness among those racers. Is having the heavier bike going to have a big enough effect on you where you wouldn't be able to keep up? How much effect do those 6-8lbs matter.

Thanks,
CD

Voodoo76

Zero, Zip, none. It won't matter.

snoboard2

well i went from racing a 25lb bike to a 15 pounder. I can tell a difference on hills plus, i went to sprint for the finish yesterday and noticed a huge jump compaired to the old bike. There's a website showing time saved at a constant wattage with 5lbs less weight up a hill...it's significant. But for keeping up, 5 lbs doesn't make a difference if you're in the pack. Try losing weight (if you have some to lose).

EventServices

For a cat 5 in his first few months of racing?
Zero, Zip, none. It won't matter.

Go race.
Talk to me in August.

Voodoo76

If you took the $$$ difference between the 22lb and 15lb bike and used that to travel and race more, in the end you will be a better racer. The experience you gain would more than offset the 2% disadvantage in wattage or whatever.

merlinextraligh

simple physics it does matter. At a level where everyone is gifted, and extremely fit, it would be the difference between winning and losing particularly on a course with much climbing. However in Cat 5 there is a wide variance in fitness, ability, and experience. You can definitely compete on a 23lb bike, and if you're stronger you can win. It won't be a deciding or limiting factor.
If you get out and do some races, and want to stay with it, you might look into getting a little bit lighter bike.

DocRay

+1, pro team bikes in TDF get up to 19lbs.

Take a 175lb rider, 15 vs 20lb bike is 2.5%, even in cat 5, fitness, trainign and diet are much bigger variables.

DrWJODonnell

As stated before, don't worry about it unless you are always 2nd place in the sprint, or are doing some stupidly long hill climb TT. Weight will only matter with acceleration which means hills, sprints, or crits, and if you are middle of the pack consistantly, you would move up from about 17th to 15th. Not worth it. Put some time into training and worry about weight after you have upgraded a category or two.

CycleDeac

Ok. Thanks for all the great answers. I'll keep working at it and I'll let you know how it turns out.

CD

tekhna

I remember hearing somewhere (and this could be wrong) but 20 pounds difference equals about 25 watts-So the difference of 6 pounds-8 pounds is not too much. Makes a difference over time, but not a massive one in most cases.

tekhna

Here is the calculator someone was referring to-It's a difference but not huge.
https://www.kreuzotter.de/english/espeed.htm

San Rensho 

No difference, assuming the combined weight of the bike and the rider are the same. And assuming they have the same wheels.

For example, Take two racers who can both produce the same output, the same no. of watts.

One weighs 150 and has a 15 pound bike, the other weighs 145 and has a 20 pound bike. In a time trial, they will cross the finish line at the same time.

Now, whats the difference in cost between a 20lbs bike and a 15 lbs bike? Prohibitive.

If you are absolutely at your lowest weight and you cannot lose another pound, then yes, in a hill time trial, 5 lbs might make a difference.

But in any group race, criterium or road race, there are so many other variables that will completely nullify any weight advantage. Having to bridge even a small gap for a while, getting caught in the middle of the pack during a few turns and having to slow more than the guys at the front, will completely negate any weight advantage.

youngster

I'm interested in this matter also because I'm sort of in the same situation. I think the quality of the wheelset is by far more important then the weight of the bike. How much of a difference in km/h is there between a wheelset of good quality vs a cheap one ? Can anyone refer to some personal experience?

pinky

Well I just raced on a set of MA-3 rims with 105 hubs and felt no difference compared to racing on Velomax Circuits or Dura Ace hubs with Open Pro rims, and that was with a small climb every lap for roughly 30 or so laps...but I'm still building up a set of light rims, either those or a keg...

DrWJODonnell

a wheelset is the best improvement you can make to your bike. Deeper rims give aero advantage (particularly for the front wheel), whereas light periphery (read: rims) severely decrease rotational inertia. Here is a link to wheels and wattage requirements.

https://www.diablocyclists.com/aerowheels.htm

I think there is another out there, but I am not remembering the link...if I come across it, i will post it here.

jfmckenna

I just got a set of light aero wheels. They weigh in at about 1500g. I think they feel faster on the jumps but I am having a hard time deciding if it's all in my head.

San Rensho 

Aero wheels will give you the most improvement in speed compared to going with just a very light set of non aero wheels.

At first, I thought that the lighter the wheel, the better, because the whole thing in acceleration is overcomming inertia, and rotating objects develop much more inertia than non-rotating objects.

I learned on this site, however, that that is not the case. Take a look at https://www.biketechreview.com/archive/wheel_theory.htm.

You will see that aero wheels are over 10 times more efficient than the lightest non aero wheels.

But also notice we are not talking big numbers here. An aero wheel saves about 1.8 % of the watts put out for the same speed, while a non aero wheel saves about .14 %.

Clearly, these small gains will be more than overcome in a real world race where one mistake or misjudgement, i.e., going with a break that gets caught, being too far back in the pack for a few laps, will negate any wattage savings from trick parts.

Doctor Who

Unfortunately, that's the reality for pretty much any amateur racer below Cat. 2. As stated before, it's only when you're a rider of significant power, experience and speed that equipment makes a more than marginal difference. You can be a Cat.3-5 state champion on a Tiagra-equipped beater bike. I've been doing road races on my cyclocross bike equipped with a set of Open Pros and I do just fine, except that I run out of gears on steep descents.

But I'm still saving up for a choice road bike. Why? 'Cause I want to, but I maintain no illusions that by buying a new bike, I'll be able to place higher in the races that I enter. Essentially, buy a tricked-out bike if you have the means to afford it, but make sure that your legs are strong enough to deserve it. It seems awful to say, but you never want to be "that guy" who comes out to a race on a $6000 Fondriest and who gets dropped on the first hill.

Plus, I couldn't imagine the heartache if I entered a Cat. 5 race on a superbike and some squirrely rider plowed me over in a corner, scratching up both my bike and my skin.

feltdude

I won my first Cat 5 race on a ~22 lb Trek 1000 with Sora. And hairy legs.

DrWJODonnell

Ok, I believed you until the part about the hairy legs. Inconceivable!

LowCel 

I won my first race on a 17.5 lb IF with record, a powertap, and hairy legs. Two weeks later I now have shaved legs and have ordered a cheaper bike. I decided to order the new bike for two reasons. First reason is I don't think I have earned the right to race a bike that expensive. Second reason is there are way to many squirely riders in the cat 5 races, I would much rather crash a less expensive bike.

timmhaan

this is why i will probably never go above a mid-priced ulterga equipped bike to race on. that's more than enough equipment.

plus, if i crash and total the bike, i'm not out thousands of dollars. i can actually afford a new one. imagine that

Keith99

A heavier bike is often designed for something besides racing. Honestly I would worry more about those other things that might go with the weight. Lack of stiffness in the BB can mean a significant power loss, esp in a sprint. A more relaxed geometry means comfort, but lack of handling as far as a racer is concerned.

But as long as the gearing is right, it has drop bars and the tires are not wide go for it. Do not pass on the experience you are looking for because the bike might limit you. If it turns out the bike is a limiting factor having a race or two under your belt will at least help you decide if a more expensive/race specific bike is worth the cost.

jfmckenna

Actually I did win my first cyclocross season, Men’s C a few years ago on a 25 pound touring bike. It actually was a nicely set up bike for cross. But on the road once I replaced it with a modern racing bike the difference was quite obvious and definitely not just in my head. I think though that the difference was more in the geometry then in the weights or probably realistically a combination of the two. My racing bike is about 20LBS.

More on aero wheels: Is the advantage in aerodynamics gained as the wheel rotates slicing through the air or is it gained as the wheels them selves move forward slicing through the air. IOW think of the wheel as not rotating but moving forward and cutting air. I guess maybe it's both, or I am not making any sense. I guess when you are talking about inertia weight savings of around 200 grams or so maybe won’t make a difference but I know when my cyclocross tires get caked up with heavy mud they are definitely harder to spin.

San Rensho 

I asked myself the same question, whether it the airfoil profile that the front of the wheel presents to the oncoming wind or whether its the spinning wind resistance that makes aero wheels more efficient. I don't think the article says what it is. Interesting question.