Punchy71

Hello,
What makes the difference between a slow bike and a fast bike? Is it the riding position of the rider? I've noticed that some bikes tend to put the rider in a more upright position and other bikes tend to make the rider lean way forward over most of the bike, which to me always looks like a backache in the making, like he's trying to be more aerodynamic or something. How are these wide ranges of rider positions accomplished? Is it the frame geometry? The component geometry? Or all of the above?
Thanks

StanSeven

The color. Red is fastest.

Then there's the curved doohickeys.

Velocivixen 

I can contribute that lighter wheels make for faster acceleration from a stop & easier climbing, due to rotational mass. Lighter frame material. When you're sitting bolt upright your torso acts like a sail in the wind so wind drag slows you down.

StanSeven

Seriously you can't make assumption that apply to everybody. But generally the lower the position, the less aero drag. Getting the hips rotated to open helps for most. It really boils down to what is most efficient for the specific rider. That's why there are sophsicated means of testing power and efficiency. Then there's the ability to sustain power - a petition to produce high output isn't helpful if the rider can't comfortably maintain it for a long period.

ypsetihw

hesuus christo, here we go again. post some power numbers or please stop this nonsense. I know you are an old dog, and I can tell by your post that you are keen on new tricks, but give this wheelset garbage a rest, will you? a couple hundred grams on wheels can easily be overshadowed by tubes and tires. aero matters more, but not that much on wheels, and what you had to eat (and drink) the night before matters most. give it a rest.

the difference between a fast bike and a slow one is the rider. you can use the wide variety of flex joints on your body, that the universe gave to you, to achieve any position that you want on any bike. a couple of grams, or even a couple hundred, or even a few pounds, is nothing compared to your body weight and your overall aero position. a tour pro will beat you on a huffy every single day. you could have a 12 lb $10k carbon bike with all the fancy stuff and I can still probably out-sprint you if you are asking this question.

here's a simple answer. does it weigh more than 20 lbs? slow bike. does it have less than 9 gears on the rear? slow bike. are you fat or untrained or not wearing good kit or whatever the hell else? slow bike.

ypsetihw

actually it matters a lot if you can make that power at the right time. I will agree that there are no simple answers, but the average posters inability or unwillingness to convey the complexity and nuanced nature of power output and bike performance is pretty sad. you need to learn/read/ride more. there are no fast bikes. there are slow riders. period

NYMXer

The bikes weight, wheels, gearing and rider posture all add up to fast or slow. In the end, Lance Armstrong would be faster on a Walmart bike than I am on a Cervelo, but I'm okay w that.
The engine (you) is as important as the bike!

Velocivixen 

@yphetihw - Thanks for the clarification. I stand corrected.

dksix

Unless you're already pretty fast, getting a high level of efficiency from the bike, I don't think the bike is much of a factor. When I started riding last year I started on a MTB, after a few (3-4) rides I got a cycling computer and started watching my averages. I was riding 20-30 mile rides after the first week or so and my average speeds started in the 10 MPH range then quickly to the high 12 MPH range. Then I bought my road bike and expected to see a significant increase right from the start. I was wrong, maybe a 5% increase in speed after getting used to the road bike.

The more miles I logged to faster I got, making it up to ~15MPH average speed now. Which is still slow but there may be ~2000' of elevation where I live on a 25-30 mile ride. The bikes are designed for a purpose, so get the style that suits your purposes and riding style then improve your strength and endurance to become faster and your skill to become quicker and safer.

ypsetihw

and I'm so dumb I thought this was a compliment . . . you know with 3300+ posts and a decent looking stable, I'd think you were capable of a better response than "get a lighter wheelset." come on people. really?! don't patronize me, or the OP, or anyone else for that matter. I will say it again. there are no fast bikes, only slow riders. you and I both know this is true. tell him the truth, don't sell f_cking bike parts.

FBinNY 

Let's not kid ourselves, it's all about the engine. After that it's a long way down to the other factors which I'll list in what I believe is the order of importance.

1- correct saddle height
2- aerodynamic body position, ie. drop bars vs upright
3- decent fit overall
4- decent tires at proper tire pressure, with narrower being preferred within reason
5- all other mechanical factors -- individually and probably even combined.
6- decently aerodynamic clothing.

In looking at the list, understand that I'm speaking about each being within reason. If any is extremely off, it would move higher in the rankings.

So my advice is to get a decent fit on a bike in decent shape, with tires properly inflated. Then work on your engine, while making necessary changes in the bike as opportunities allow. But do not fool yourself into believing you can buy speed. As I said in opening, it's ALL about the engine.

ypsetihw

right?! seriously though, this was the biggest lie that I was told when I started cycling as an adult. get this or that or more gears or carbon or this helmet or these wheels. eff it all. that's the truth. get the cheapest reasonable road bike you can find and ride it til you puke. that's the fastest bike, ergonomically speaking. the one that makes you ride til you puke and do it again every day.

Velocivixen 

Of course there are many factors which contribute to being able to ride faster, as posted by several of you already. I was under the impression that lighter wheels in cooperation with lighter wheels/tubes that this would be one contributing factor. Certainly not the primary or only factor.
@ypsetihw - I was actually thanking you seriously and being somewhat tongue in cheek that you reacted so strongly. I learn new things here all the time, so I have no problem saying when I'm incorrect.

StanSeven

You're not wrong with your weight statements. It's just that they are of much less importance than many other things stated already. The one thing that isn't really factual is lighter wheels and climbing. The absolute weight difference helps the first time you accelerate but after you reach a steady state, wheel weight doesn't make any more difference than other bike weight. Zinn had a really good test posted a couple years ago on that.

Velocivixen 

@StanSeven - Thanks for reference to Zinn. I will look it up and read. Always good to keep learning and understand the dynamics of movement.

jamesdak 

LOL, will I'm really going to set you off. I agree that lighter wheels do make a difference and are worth it. As someone who climbs a lot it matters. Why does it matter? Because if I'm heading up thinking, "man, these wheels spin out easy and keep going on this grade," then the ride is more pleasant than it it when I'm heading up on a much heavier set groaning about the weight and not enjoying myself and staying mentally positive. So there.

Oh and I just set a PR on my 31 mile training route on a bike that weighs over 20 lbs. In fact this was my fastest avg pace for any ride, of any distance, on any of my lighter bikes since 2013. So, what'll you got to say about that?? Crap but wait a minute, it's got "heavy" wheels at around 1860 grams and no aero benefit. Dang it!!!

ypsetihw

@Velocivixen thanks for being casual and candid. frankly as a big but strong rider on a budget, I often get crap, especially on here, for my choice of components and so on. in particular, weight is something I'm a sensitive about because at 205lbs/93kgs before kit and food in my belly, 400 grams in wheel weight isn't helping me at all, climbing, sprinting, or otherwise. in fact, your water bottles weight probably 2lbs a piece, but everyone seems to over look that. but the reality is that I can out-perform, and put out bigger power numbers than, 3/4 of my group riding companions, on very budget oriented kit. I get a bit flustered, as a long time athlete and performance enthusiast, that cost or weight equals performance. in reality, sometimes weight EQUALS stiffness and therefore performance, not the other way around. sorry for reacting so strongly

I know what you were getting at, and perhaps a more specific and scientific answer would be to say that grip and rolling resistance make for a faster "feel" on the bike, which is generally, but not always, related to tire width, pressure, and overall wheel weight. for ME, lightweight wheels tend to go out of true very fast, which results in poor performance overall. unless you are racing crits, where repeated accelerations are the name of the game, "getting up to speed" is much less important than being able to maintain speed, in which case aerodynamics is more important that ergonomics, and drafting trumps literally everything in this regard. in other words, learning to ride in a group intelligently, and leveraging your skills and group position, is much more important and effective than literally ANY upgrade that you can buy. but I digress . . .

it still comes down to the motor. you know what my biggest upgrade was this year? lifting weights and riding the trainer all winter . . .

jamesdak 

Holy crap, come on out with me and ride the 35 mile long climb up Monte Cristo and hold a steady state. Maybe better men than me hold steady on any real climb but I know I sure don't.

ypsetihw

I 100% agree that mentality is almost everything. but aren't you kindof making my point for me? you set your PRs on your heaviest bike with your heaviest wheels . . . 1860 btw? that's not too bad. my 37mm vueltas are over 2000gr without tires and tubes and I run a 25mm front and 28mm rear, so I basically have boat anchors on the rim. I thought about running 23mms with 200 psi and wheel weights from a ford explorer clamped to the brake track, but I couldn't get over the look cosmetically . . . LOL

Carbonfiberboy 

I don't know how things go so far off the rails in a simple thread like this . . .

Four things about rider position affect the speed of a bike:
1) The rider's ability to produce power.
2) The wind resistance of the rider.
3) The length of time that a good speed can be maintained; the longer, the better.
4) The ability of the rider to handle the bike safely.

The standard road position with the rider's torso bent forward at about a 45° angle has been virtually unchanged on over 100 years. The reason for that is found in #3 . It's the most comfortable position for long rides. Helpfully it's also the best position for #1 and very good for #4 . It's not the best position for #2 , but #3 and #4 trump everything but for short races: time trials.

The exact why of all this would involve a long discussion.

The comfort part is fairly quick though. Leaning forward allows the spine to flex naturally and reduces compression loads on it, and thus also impact loads on the sit bones.

It's common for beginners to think that the road position will be uncomfortable. Manufacturers understand this and so produce a variety of entry level bikes which feature more upright positions. But if you watch riders on any recreational group ride, you'll see that all of them are in some variation of the standard road position.

Mountain bikes use about the same position as the standard road position, even though these bikes are intended for riding in very different conditions. Still, #s 1-4 still apply.

StanSeven

Haha. I didn't mean that. What I was trying to say that wheel weight doesn't matter any more than any other weight once you get going. Lighter weight wheels have a very slight difference accelerating but it's a one time shot.

ypsetihw

not a single one of these has anything to do with the ergonomics of the bike. 1. riders ability. 2. wind resistance. 3 riders ability. 4. riders ability.

also, this is a forum, and talking to other people is fun, which is how this conversation got so far off track. I would hate to run into you at a bar . . . god forbid the conversation wandered a bit.

jamesdak 

Ummm, well..... dang it!

StanSeven

Ypsetihw,

Glad you said that. It's a reminder we all are here for enjoyment and learning.

btw that was a nice post you did above to velocivixian

canklecat

For me, it's body position. I can loaf along all day at 12 mph on my comfy hybrid with upright bars. Faster than that and I feel the effects of wind resistance more than anything else. When riding into stiff head winds I'll lean my forearms across the bars to reduce my profile a bit. According to some apps it helps boost my average speed to 14 mph.

But I don't see myself returning to the drop bars lower than saddle height I rode years ago. A permanent neck injury makes that position uncomfortable for more than a few minutes at a time. But it's definitely a big help if you can handle the position on an ergonomically well designed and fitted bike.

Other factors, in not particular order (again, for me, not a statement of absolutes for every rider)...

• *Frame geometry. My hybrid is designed for comfort, not speed. Long wheelbase, slightly pedal-forward design, etc. If I scoot forward I can pedal with a bit more power but only for short distances, such as uphill while seated. It's not a natural position for this bike.
• *Tires. My current tires are about a third heavier than the originals, with thicker puncture resistant shield and more heavy duty all terrain tread. Not fast, but great for the mixed surfaces I ride that are littered with sharp pokey stuff. And the sharp edged shoulders feel squirmy on high speed turns.
• *Foot interface. This covers pedal design and shoes. Years ago (pre-clipless), I rode lightweight metal pedals with Detto Pietros which had lightweight leather uppers and steel shank soles with metal cleats snugged down into metal toe clips. All of that contributed to efficiency over the long haul, especially on hills (up and downhill). Nowadays I wear thick soled hiking shoes or thin soled boat shoes with flexy nylon platform pedals. I know I'm losing some efficiency but not enough to be a major factor until I'm in much better aerobic condition.
• *Fork. My bike has a simple spring suspension fork. Very comfy for my back and neck, but it robs some efficiency. I'll never be able to handle a stiff fork for anything but smooth pavement, but I may eventually try a more road-oriented bike with curved steel fork. I'll need to ride at least 50 miles on any given day on my current bike before I'll be ready to consider an upgrade.

Biggest change I could make to my current bike would be flat or nearly flat handlebars. Due to a long term chronic neck injury I have to make adjustments gradually and try it for a couple of weeks to a month at a time. So far over the past six months I've lowered the stem to the minimum height (still well above saddle height), and recently tipped the handlebar forward a bit to let me stretch out without hunching my shoulders. I noticed in some videos I took of myself riding that I was in a slightly hunched position with my shoulder blades squeezed together and back arched more than necessary. So I'm gradually making small adjustments and getting used to each incremental change until I feel ready for a more major change, either in the handlebar itself or a different bike.

And if anyone wants to lend me a featherweight carbon frame road bike to try for a day I'll be happy to change my tune for my personal standards if it turns out to be the bee's knees.