Elduderino2412

Just curious how much difference a lighter bike makes. My current beginner bike is about 23 pounds(giant ocr2) with tiagra/mixed groupset. I'm 6'2" 205 lb, and currently doing 17-18mph on flat 20mi course(i just started month ago). Not ready to buy yet, but down line i will be. Wondering how much speed difference a lighter bike makes. I'm looking at maybe a Cervelo S3 ultegra or in that price range.
Sure this gets asked all the time, but couldn't find anything by searching. Thx

Right Said Fred

Lighter bike won't improve the engine. Focus on that first.

simonaway427

Work on your fitness first. A nice bike means nothing if the rider is slow.

StanSeven

Do a search and you'll find bike calculators that show speed different with various weight. I recently used one that showed a 0.25 mph difference by reducing rider/bike weight 5 lbs on a 222 lb package (180 lb rider and 22 lb bike - bike reduced to 17 lbs) on a 5% climb. On the level, there's no difference.

An aero bike like a S3 will save you two minutes on a 25 mile course over a regular bike.

Bottom line - weight only makes a difference on hills and it's not that large.

jmX

On a flat course, the weight means pretty much nothing. In your case you'll gain no noticeable speed from losing weight off the bike. You will get faster if you lose body weight, as that'll be less mass to keep oxygenated - plus a slimmer profile will have less area fighting the wind.

Start riding up mountains, and then the ultegra bike might make more sense.

Elduderino2412

I'm nowhere near ready to buy a bike. I was mostly just curious. I'm naturally kind of competitive in sports, so i was just wondering what difference it would make down the line. I'm working on the engine pretty much everyday. Thanks for the info

chasm54

Lose weight. Get more aero. Work on increasing your threshold power. Think about buying a lighter bike. In that order.

Elduderino2412

i've been struggling w/ the concept of losing weight, mostly for vanity reasons. I've decided i will probably get down to 195 or so for now, and do a little less intensity on weight training. Possibly later i will cut more weight, since i really seem to enjoy cycling.

Shimagnolo

Don't listen to the naysayers, a lighter bike makes a *huge* difference...in your wallet.

But if you want numbers, go here: https://bikecalculator.com/veloUS.html

chasm54

You can be vain and light. This guy is about your height and weighed under 190 when this picture was taken. Admittedly, he was the Olympic 100 metre champion at the time, but it seems clear that losing fat rather than muscle is the answer. https://www.google.co.uk/search?q=lin...iw=768&bih=928

IcySmooth52

I'll say again, the engine matters more. Don't think of a new bike unless...
1. Your current one has had enough miles and isn't worth refitting the components. (A rarity)
2. You want a cooler bike that handles amazingly to you. Or you can't resist the looks of one.
3. You want a bike that fits your riding style more. Example: centuries and distance are a focus, not timing laps. You also prefer a club ride, not a race. So get a plush style bike instead of a crit racer. Or vice versa.
4. Your bike is the wrong size for you.
5. You're racing on a CAT 3 or higher level. Then the bike can make a small difference in weather or not you win.

Elduderino2412

yeah your probably right. He looks better in spandex than i do.
BTW wasn't he the steroid guy?

Edit: Maybe it was Ben Johnson from Canada i'm thinking of

chasm54

Nandrolone, I think.

sqroot3

if a light, sexy bike that you can afford makes you ride more, the expenditure is likely justified and you'll get faster!

Drew Eckhardt 

Essentially zero on flat ground.

Proportional to the ratio between the total bike + weight combinations on suficiently steep hills.

For instance, a 205 pound rider atop a 23 pound bike totaling 228 pounds can expect to be 3.6% faster up the steepest hills when he drops to a bike at the 15 pound UCI minimum. He'll save two minutes for every hour he spends climbing.

Upgrading to a 20 pound bike will only make him 1.3% faster though.

StanSeven

The bigger question is can a 205 lb rider on a 23 lb bike on the steepest hills ride for an hour?

dennisa

I can attest to it's not the bike it's the engine. I had the chance yesterday after work on a group ride, sponsored by a local bike shop, to take out a Raleigh Militis 3 for ~30 miles ride. Very similar geometry to my CAAD9. Stock out the bo the Militis is about 4-5lbs lighter than my CAAD9. Overall the ride was just as harsh comparing carbon to aluminium, the frames felt equally rigid. Was I faster on the Militis not really, It may have felt faster but it was most likely a plecebo effect. The only time during the ride that I could feel the weight difference was on one particular decline that has a sharp incline about half was into the descent and then begins a decline again.

Overall instead of spending $6500 on the Militis, it would be much more cost effective for me to lose a few pounds to achieve the same results from the ride yesterday.

DropDeadFred

lighter is always better /thread

Carbon Unit

Depends on the rider. It is all about power to weight. The founder of my bike club is 280 lbs but is a very strong rider. He started the club over 30 years ago and has probably riden three times a week for the past 30+ years. He also rides a bike with rack and bags on it. The bike probably weighs 30 pounds with all the crap he has loaded on it. I wouldn't call him fast but he can maintain a fast pace for hours at a time including on hill climbs.

RecceDG

There's an interesting table in Cutting Edge Cycling that shows that, while weight does pay some dividends on hills, a heavier, more aero wheel will actually save more time on a hillclimb TT than a lightweight, less aero wheel on all but the steepest climbs.

If you aren't doing HC climbs, a little bit of weight savings doesn't make a huge difference. It does make a difference, but the scale is pretty small.

Weight makes a bigger difference on the rider, mostly because there is typically so much more of it to lose. It's nearly impossible to take 10lbs off a modern bike, but for most of us, dropping 10 lbs would be "a good start".

DG

halfspeed

Why wouldn't it make a difference in a lower cat?

big chainring 

Ever since Eddy, orange bikes are faster. Weight doesnt matter, its the color of the bike.

StanSeven

Exactly. It doesn't make a difference what cat or even if you're a racer. The proper point is a new bike can make you marginally faster under the right circumstances. It's up to the buyer to decide if it's worth the money. This thing about what CAT doesn't make any sense.

DGlenday

I get so tired of reading this - because it's such a HALF-truth.

On the level, at a fixed speed, there IS a difference, though I agree that it's small. So the claim that it makes no difference on the level is partly true.

However - the miniscule advantage of low weight is only true if you're in a very flat area and riding at the same speed for many miles. If that describes your riding, than stick with what you have - posts like the one I quoted are correct.

But the moment you start hitting even slight rollers (which describes probably 75% of the cycling routes in the USA) then the weight does make a difference. And the moment you start riding with others, you'll have to accelerate from time ti time. And in acceleration, weight makes a big difference. (Elementary physics. If F=MA, then A=F/M. I.e. Acceleration is a function of force and mass.)

I agree that a lighter engine will be a far cheaper and easier investment than a cheaper bike, and I agree with holding off on an upgrade until you've built a lot more capability. But yes, weight does matter.

fiataccompli

I'd say weight makes a difference but not enough to justify spending a bunch of money (unless you really want to spend some money). I regularly ride a range of bikes from a 16lb (maybe) Orbea with SRAM Red to a some 22-24(ish)lb steel bikes with Shimano 600 downtube shifters, etc. & probably 6-8 bikes that fit somewhere between those ends of the spectrum in terms of weight/materials/components. Last fall I did about 70 miles with a group on a 23lb Bridgestone RB-1 with 7 speed/dt shifters and averaged in the low 20s (maybe 22-23?)mph (I wasn't planning on riding particularly fast, but just ended up with a group & kept on). I weigh about 168lb & generally ride about a 55cm bike. What I've noticed is the CF accelerates faster which essentially gets up to a cruising speed faster & is a bit lighter climbing. The heavier bikes end up with the same inertial forces posted above but as an advantage...inertia also means a bit less force req'd to keep the bike in motion once you get rolling up to a nice cruising speed....so, there's a bit of a trade-off, or perhaps it's more accurate to say there's a minor advantage you realize in parts of a road ride so the divergence between the modern, light bike is maybe less than it would initially appear in theory. Ultimately, I believe (for me at least) that until I am riding & racing competitively (which, actually, I don't really intend on doing), all of the light weight stuff is optional and what I need to be working on is technique and my own general fitness (core strength, weight, endurance, etc.) and just enjoy my array of bikes to chose from. When friends ask me about whether they should get light bikes, light wheels & all that to make them faster, I usually tell them to get a really nice steel framed bike from the '80s, outfit it with modern components & ride the hell out of it along with the regular carbon fiber crowd....and once they can do that, they will be faster...but, hey, maybe I just like doing things the hard way. You can't say enough the engine is the largest part.

Oh, and I guess when you're on that bubble of being popped off the back of a group, it's fair to say that every small advantage will help so sure, a lighter bike may keep my from being dropped....BUT...at the level I am riding I can also get there by improving my fitness & ultimately become a better rider.