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Who Counts Grams for Cycling?
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I've seen people during an Ironman with 2 bottles behind the seat, 1 bottle on the down tube and another on the seat tube. If all of the bottles are 20 ounces, then it's 2,268 grams or 5.0 US Pounds.

Noticed that the Shimano Dura Ace Di2 shifting is 561 grams more than the 105 Di2, which converting that to 1.2 US pounds.

An old tri-friend, nicknamed Popeye, used to remove chain links before a race to make his bike lighter.
My son would remove the plastic cover from the top of his presta valves to make his wheels lighter.
Others fret over the grams for a tire or a tube compared to another brand.

Personally, I find myself adding comfort to the bike, even if it means adding a few grams.

Why do bicycle riders fret so much over a few grams? Can anybody articulate when they removed 500 grams from their bike and went from a non-Kona slot to a Kona slot because they were 27 seconds faster on their bike split?
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Re: Who Counts Grams for Cycling? [candyman] [ In reply to ]
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candyman wrote:


Why do bicycle riders fret so much over a few grams? Can anybody articulate when they removed 500 grams from their bike and went from a non-Kona slot to a Kona slot because they were 27 seconds faster on their bike split?


Speaking from the roadie - not triathlete - perspective. In road races the climbs are often the critical parts of races. And being just a handful of seconds faster/slower over the top of a serious climb can mean the difference between competing for a win and finishing 20 minutes behind the winner. A very recent roadie example is Richard Carapaz got within about a wheel length of Pogacar on the La Redoute climb. And was maybe 6 seconds behind him over the top. He finished in 26th place. So weight really matters a lot if in those situation. Ditch all your water bottles before taking on Pogacar!

And sometimes it can just be fun rather than any real performance concern. Some people trick out their cars even though the car will never see a track. It's fun to trick out a bike - and usually far cheaper than tricking out a car. Fretting over titanium vs. aluminum bolts is more the fun type of fretting, than the serious kind.

And sometimes people just aren't aware that weight isn't a huge deal on flattish terrain.
Last edited by: trail: Apr 24, 24 16:51
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Re: Who Counts Grams for Cycling? [candyman] [ In reply to ]
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This does remind of a billboard near me that says, "Do It For the Grams!" showing a mountain biker in full send.

Took me a long time to realize it was a marijuana ad.
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Re: Who Counts Grams for Cycling? [candyman] [ In reply to ]
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IDGAF about comfort, but if you're trying to go faster weight is not the answer.

From a first pass standpoint, in triathlon climbs are not the race-winning moments. In UCI races where climbs are, there is already a 6.8kg limit, so just hit that an who cares. (a complete tangent, Speedplay pedals are stupid. Why would you take weight (locking mech) FROM the weight restricted entity and ADD it to the unmeasured entity>?!?!?!)

FWIW climbing Alpe d'huez at 300w and 160lb system weight would take 53.90min, at 159lbs would take 53.64min. A FULL 1 POUND of weight only gets you 16s up Alpe d'Huez.

Explain to me the use case for a weight-reduced bicycle. IMO mos people I've met who are obsessed with the weight of their bike have >a full bike weight to lose off of themselves.

I say, as has been said. Aero is everything.
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Re: Who Counts Grams for Cycling? [mathematics] [ In reply to ]
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mathematics wrote:
(a complete tangent, Speedplay pedals are stupid. Why would you take weight (locking mech) FROM the weight restricted entity and ADD it to the unmeasured entity>?!?!?!)
Can you explain and provide some context here? Seems an interesting point that you feel strongly about!

Dr. Alex Harrison | Founder & CEO | Sport Physiology & Performance PhD
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Re: Who Counts Grams for Cycling? [mathematics] [ In reply to ]
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mathematics wrote:
IDGAF about comfort, but if you're trying to go faster weight is not the answer.

From a first pass standpoint, in triathlon climbs are not the race-winning moments. In UCI races where climbs are, there is already a 6.8kg limit, so just hit that an who cares. (a complete tangent, Speedplay pedals are stupid. Why would you take weight (locking mech) FROM the weight restricted entity and ADD it to the unmeasured entity>?!?!?!)

FWIW climbing Alpe d'huez at 300w and 160lb system weight would take 53.90min, at 159lbs would take 53.64min. A FULL 1 POUND of weight only gets you 16s up Alpe d'Huez.

Explain to me the use case for a weight-reduced bicycle. IMO mos people I've met who are obsessed with the weight of their bike have >a full bike weight to lose off of themselves.

I say, as has been said. Aero is everything.

As was already mentioned, its more about the hobby of tricking out the bike. I don't think anyone truly believes that knocking a pound off their bike is gonna put them on the podium.
And speedplays aren't for the (non) weight savings, they are for the smoother/wider rotation that some folks want or need.
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Re: Who Counts Grams for Cycling? [trail] [ In reply to ]
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trail wrote:
candyman wrote:
In road races the climbs are often the critical parts of races. And being just a handful of seconds faster/slower over the top of a serious climb can mean the difference between competing for a win and finishing 20 minutes behind the winner. A very recent roadie example is Richard Carapaz got within about a wheel length of Pogacar on the La Redoute climb. And was maybe 6 seconds behind him over the top. He finished in 26th place. So weight really matters a lot if in those situations.
Bingo. Aero is everything, until it's no longer the limiting factor in your race.

USAC Road nationals is probably a great example of this. Flat boring course with laps, except for two major decisive climbs each lap. It's been the same story for a decade. When it was in TN (it's in WV now) it was also several laps of a mostly boring course with one major decisive very steep climb. The rest of the race, 50% of the racers could have solo'd around the race course at the same speed as the peloton because they, quite frankly, dog the flat sections.

Every year, the make or break moment happens on the steepest portion of the climb, and all the attacks, all race, happen up and over the same steep section of the same climb. You make the split, and you're in it for the win. Every year. Same story.

Dr. Alex Harrison | Founder & CEO | Sport Physiology & Performance PhD
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📱 Check out our app → Saturday: Pro Fuel & Hydration, a performance nutrition coach in your pocket.
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Re: Who Counts Grams for Cycling? [candyman] [ In reply to ]
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candyman wrote:
My son would remove the plastic cover from the top of his presta valves to make his wheels lighter.

Who leaves them on??

blog
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Re: Who Counts Grams for Cycling? [DrAlexHarrison] [ In reply to ]
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DrAlexHarrison wrote:
mathematics wrote:
(a complete tangent, Speedplay pedals are stupid. Why would you take weight (locking mech) FROM the weight restricted entity and ADD it to the unmeasured entity>?!?!?!)
Can you explain and provide some context here? Seems an interesting point that you feel strongly about!

Yeah of course. The bike is weight restricted to 6.8kg, it's not terribly difficult to get below this, esp if money is no object. There is no weight limit on the rider, or their equipment other than the bike. If you have a bike that's under 6.8kg you need to add ballast until it hits the limit. A clipless pedal needs a retention system.

There's a situation where your bike weight 6.7kg with Speedplay pedals. The cleats weigh ~100g more than delta style ones. The bike is going to weigh 6.8kg no matter what pedals you use, so you've increased the system weight by ~100g.
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Re: Who Counts Grams for Cycling? [candyman] [ In reply to ]
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removing chain links? the point of a lighter bike its to go faster up hills.... without the chain links cant shift into the granny gears so the point of lightness would be defeated. Maybe removing low gear cogs in the back...
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Re: Who Counts Grams for Cycling? [mathematics] [ In reply to ]
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Got it. I had no idea speedplay cleats weighed that much more. I see the conundrum. I suppose they didn't consider that a limiter to their sales since most consumers buying them are buying them for relatively flat TTs.

Dr. Alex Harrison | Founder & CEO | Sport Physiology & Performance PhD
-------------------------------------------------------------------------------------------------------------------------------------------------
📱 Check out our app → Saturday: Pro Fuel & Hydration, a performance nutrition coach in your pocket.
Join us on YouTube → Saturday Morning | Ride & Run Faster and our growing Saturday User Hub
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Re: Who Counts Grams for Cycling? [stevej] [ In reply to ]
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stevej wrote:
candyman wrote:
My son would remove the plastic cover from the top of his presta valves to make his wheels lighter.

Who leaves them on??


Yep, leaving them on is just plain dork.
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Re: Who Counts Grams for Cycling? [DrAlexHarrison] [ In reply to ]
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People buy Speedplay pedals because they only look at the weight of the pedals and don't have any idea how heavy the cleats are.
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Re: Who Counts Grams for Cycling? [jimatbeyond] [ In reply to ]
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jimatbeyond wrote:
People buy Speedplay pedals because they only look at the weight of the pedals and don't have any idea how heavy the cleats are.

I thought it was because they were aero.
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Re: Who Counts Grams for Cycling? [candyman] [ In reply to ]
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You cannot really argue this point with roadies and people who have their mind made up. Weight was the single defining, measurable performance factor on a bike until power meters became widely available. That means decades of people believing one thing cannot be overturned by facts they don't want to believe.

Let's take Dr. Harrison's US Nationals example of the one decisive hill always creating the break. Let's just say for the point of argument that it is 1 km at 10 percent. That is 100 meters of climbing. So one full pound on that climb costs you about 1.4 seconds. For me, using the calculators, 1 pound means about 1 watt of power. IF you did the lap 15 times that would be 25-27 seconds. Except that they don't go crazy all out every single time up. Early on it is a lot more relaxed, so it is not really significant on every lap because as long as you are below a certain threshold, you can hold that power all day. So really that weight penalty only hurts you on maybe two or three climbs, so on those two or three climbs you have to produce an extra watt to keep up.

Sound ridiculous? Well it is, but cyclist have believed it for so long you can't change their mind on this, plus the bicycling industry has no interest in changing it because super light parts make them money.

The argument becomes even more vehement when discussing wheels even though it has been shown that wheel weight is the same as any other weight on your bike.
Last edited by: cdw: Apr 25, 24 11:52
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Re: Who Counts Grams for Cycling? [aravilare] [ In reply to ]
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aravilare wrote:
jimatbeyond wrote:
People buy Speedplay pedals because they only look at the weight of the pedals and don't have any idea how heavy the cleats are.


I thought it was because they were aero.

More aero, more adjustable, more walkable.
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Re: Who Counts Grams for Cycling? [cdw] [ In reply to ]
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Weight was the single defining, measurable performance factor on a bike until power meters became widely available.


Not at all true. Double disc wheels for roadies pre-dated PMs. Most of the famous track pursuit/hour record bikes effectively pre-dated PMs. SRM has started doing stuff by the 80's, but very few people were using them.





cdw wrote:
So really that weight penalty only hurts you on maybe two or three climbs, so on those two or three climbs you have to produce an extra watt to keep up.



It only takes one climb to matter. If a climb is a selective part of a road race, the fastest climbers will then choose to drop everyone they can. Push everyone until there are no extra Watts go give and gaps start to form between riders. When there are no extra Watts to put out, suddenly 10's of grams start to matter in the tiny gaps that start opening. And the tiny gaps *matter*. I think there's a long course triathlete misconception about the effect of drafting since (joking aside) long course triathletes don't spend much time drafting. Being 1-2 seconds off someone at the summit of a climb can be a game-ender. Even on a non-summit finish. Once you're out of the draft, you can be instantly in deep, deep trouble.

Weight matters when there's significant climbing. It just does...physics and all. This is also why many roadies who excel at climbing have crazy low bodyfat, often to unhealthy-looking levels. Weight matters.
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Re: Who Counts Grams for Cycling? [trail] [ In reply to ]
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Well, we will have to agree to disagree. There are so many factors that go into that final surge to make the break or not that one watts really is not that significant. My point was not to show that weight did not matter. It just doesn't matter very much when put up against other factors. Pogacar made a big deal a couple years ago when disc brakes were first coming on saying his rim brake bike was 300 grams less than his disc brake bike. Now we are talking about fractions of a watt.

There are so many more important things to worry about than weight on your bike.
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Re: Who Counts Grams for Cycling? [cdw] [ In reply to ]
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cdw wrote:
Pogacar made a big deal a couple years ago when disc brakes were first coming on saying his rim brake bike was 300 grams less than his disc brake bike. Now we are talking about fractions of a watt.

Colnago reportedly put a lot of effort into getting the the V4Rs under the 6.8kg limit, and apparently succeeded...so Pogacar doesn't need to ride the rim brake model.

Some teams were so concerned about every gram over the UCI limit they took the paint off the bike of their GC leader....Jumbo on their heavier Bianchi frames.

Weight matters that much to them.

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There are so many more important things to worry about than weight on your bike.

Sure, but as I noted in my first posts, for us largely recreational riders it's all silly fun anyway. Do aero calf sleeves really matter for me, a 50 y.o. masters TTer or following the "rule of 105"? Of course not. It's just fun to play the TT tech game.
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Re: Who Counts Grams for Cycling? [candyman] [ In reply to ]
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Because it's easily measurable with consumer grade scales and the physics doesn't lie. Compare 2 components that are the same price. If there are no physical features that make one better than the other for the application, pick the lighter one. Do this for each component on the bike, and the bike could be over 1lb lighter for the same price with no tangible decrease in performance. Free speed!

The 6.8kg bike with or without speedplays described in this thread already implies prioritizing weight to hit that number. On the trek website, the top end Emonda is 15.99lbs out of the box, the Madone (which will be a faster bike in almost any situation) is 1lb heavier. Additional thought is required to get those down to 6.8kg.

Some people wont even look at a bike if it has anything less than Ultegra or Force, then bolt on a bunch of useless stuff that makes it heavier than the Rival, 105 build...
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Re: Who Counts Grams for Cycling? [candyman] [ In reply to ]
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candyman wrote:

Why do bicycle riders fret so much over a few grams? Can anybody articulate when they removed 500 grams from their bike and went from a non-Kona slot to a Kona slot because they were 27 seconds faster on their bike split?
I was actually speaking from a cycling standpoint where you climbed to the top of a hill. In triathlon, it makes even less sense. I argued this once about ten years ago and was attacked so many times that I had to perform and experiment. I filled up a water bottle with sand/water and a seat bag with tools so that I could add 10 pounds to my bike. I went out and rode my 10K test loop that I use which has several hills in it, but what I would consider pretty normal for a tri bike leg. Riding the same wattage, I was able to hit the same time on both laps within two seconds (a lucky, low-wind day). Ten pounds made no difference over 10K of rolling cycling. If ten pounds did not matter, then 1-2 pounds probably won't make much difference either.

If only I could go back and not ride Tufo tubular tires at 160 psi in the early 2000s. That would have mattered.
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Re: Who Counts Grams for Cycling? [trail] [ In reply to ]
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“Tell me you don’t understand how road racing works, without telling me”. As Trail has very eloquently expressed, being 1/2 second off a wheel at a decisive moment in a road race can be race over. For a long course triathlete, no, for a road cyclist on hilly courses, absolutely.

Are there other things equally as important, or more so. Yes. But that doesn’t remove the fact that at times, weight matters.
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Re: Who Counts Grams for Cycling? [cdw] [ In reply to ]
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cdw wrote:
candyman wrote:

Why do bicycle riders fret so much over a few grams? Can anybody articulate when they removed 500 grams from their bike and went from a non-Kona slot to a Kona slot because they were 27 seconds faster on their bike split?
I was actually speaking from a cycling standpoint where you climbed to the top of a hill. In triathlon, it makes even less sense. I argued this once about ten years ago and was attacked so many times that I had to perform and experiment. I filled up a water bottle with sand/water and a seat bag with tools so that I could add 10 pounds to my bike. I went out and rode my 10K test loop that I use which has several hills in it, but what I would consider pretty normal for a tri bike leg. Riding the same wattage, I was able to hit the same time on both laps within two seconds (a lucky, low-wind day). Ten pounds made no difference over 10K of rolling cycling. If ten pounds did not matter, then 1-2 pounds probably won't make much difference either.

If only I could go back and not ride Tufo tubular tires at 160 psi in the early 2000s. That would have mattered.

You could calculate this. The time you lose will depend on a lot of factors.

Assuming you need to brake on downhills, any additional speed gained from weight will be lost there as the corner speed will be similar regardless of weight.

Rolling resistance will be higher

But most critically, the increase in acceleration due to mass scales linearly, but the increase in drag scales exponentially.

You could actually simplify the whole thing to say a vertical climb and a vertical descent on an 100 mile long hill (to effectively remove acceleration).

On the uphill at let's say 500w since it's vertical, it's 80kg=5515min, 100kg=6894min. (That's actually for a 200% grade because I'm dumb and don't feel like redoing the calc)

On the downhill for 80kg, 0.47 cda your terminal velocity is 117.8mph. For 100kg it's 138.7mph. 50.9 v 43.3 min

Gaining 7 min on the descent to lose 1,300 min on the climb.

-----
People like to make their bikes light because you can pick it up and instantly feel how light it is. Not so for aero, stiffness, rolling resistance, etc.
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Re: Who Counts Grams for Cycling? [trail] [ In reply to ]
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trail wrote:
aravilare wrote:
jimatbeyond wrote:
People buy Speedplay pedals because they only look at the weight of the pedals and don't have any idea how heavy the cleats are.


I thought it was because they were aero.

More aero, more adjustable, more walkable.

And bikes in the pro peleton aren't hovering around 6.8kg anymore, anyway.
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Re: Who Counts Grams for Cycling? [trail] [ In reply to ]
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Two seconds gap in time expressed as a distance is a lot shorter on the climb at 12mph versus after the top at 60mph downhill and 30+mph on the flat to the finish. It’s not draftable. So they are dropped:
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