what weight do you think each aspect of a bike ride affects your efficiency or speed? are they all equal, or do so some matter more?

riding surface
bike type
tires
wind
human motor
ambient temperature
bike weight
bike age
quality of components such as wheels & bearings
other

had a slow painful ~20 miles ride with a strong wind last night & started me thinking why did I perform so poorly
for me, last night, I think it was: motor, wind, tires, bike, in that order
the ride took approx. 2 hrs (30 minutes longer than it should have)

quality of components such as wheels & bearings
human motor
other
ambient temperature

Lightweight low MOI wheelset is tops

Is this over the same course/route? If so, for me it would be temperature/conditions/wind. High heat will have more of an effect than the rest. High heat + tough route and wind means a call to the SAG wagon. I had 2 12 mile runs over the last 2 weekends. The same conditions over almost the same route. One had 1020ft of climbing.The other was 1080. The only difference was that at a point I usually turn around, I decided to go an additional 1/2 mile up a gradual hill, then make my turnaround there. That additiona climb didn't seem like much at the time, but I was pegged at the end of that run. Felt a lot more tired with about 3 miles left than on the other run.

Some personal estimates of speed influences:

riding surface 3% (pavement only)
bike type 2% (road bikes only)
tires 1% (road tires only)
wind 30%
human motor 50% (trained vs detrained)
ambient temperature 2%
bike weight 2%
bike age 0%
quality of components such as wheels & bearings 0%

Wind can kill or boost speed, but the strongest variable is the motor.

For road biking on pavement, this pretty much gets it, though extreme heat can have a bigger effect. If conditioning is a constant, then it's wind, wind, wind. The rest require extreme deviation from the norm to have a significant effect.

100% bike age ... clearly.

Road grade should get another 30% from human motor if it's not a loop. Climbing a long mountain is a whole lot slower than coasting down the other side

I'm thinking the extra time it took you is mostly that you are out of shape from staying inside all winter long. Get another dozen rides in before the end of March and then see how you do!

Although this isn't weight, a very important factor is the fit of the bike. Relative position of pedals, saddle, handlebars. Two bikes can fit you with vast differences in these parameters. An upright position will have you putting less power to the pedals vs a more leaned-over position.

I haven't found that to be true for me. I produce the same or more power when sitting up with hands on the tops. Sitting up may be slower, since the wind drag is higher, so I tend to sit up only on climbs, where the speed is already lower and the aero penalty is minimal.

Wind is the biggest factor and will have the biggest effect your speed and performance... It doesn't matter how fit you are, it doesn't matter how much your bike weighs, it doesn't matter how expensive your bike is. A strong headwind will slow you down a lot and you won't be hitting any PRs. The best thing to do on windy days is to relax, take it easy and enjoy the ride.

100% color

Tires are absolutely an enormous factor. I updated my Giant from Schwalbe Marathons to Continental GP5000s and my Dahon from cheap no-name Chinese tires to Continental Urban Contacts and the difference in speed has been significant. My average speed on rides on my Giant went up from 28-29km/h on the Marathons to 30-32km/h on the Continentals, while on the Dahon I also saw an improvement of 2-3km/h in my average speed or even more (was able to average over 27km/h on it on a 65km ride over the weekend, which was far better than I was ever able to get before). Everything else was exactly the same as before.

Wind drag and motor for me. My top speed is that which I can achieve before I run out of juice pushing my body through the air. Since I'm not a super strong rider, I probably don't ride at speeds where the other factors come into play. Then hills.

What I know for sure is that I ride slower into a headwind. Therefore air resistance is a major factor. I ride slower going uphill.

In other words, the top factors are the ones you'd guess by just thinking about the physics for 2 minutes.

I ride with an upright posture, by necessity: "My neck don't bend that way no more."

Human motor - 95%. You go faster when you pedal harder.

I can not believe nobody mention the color of the bike yet, We all know Red bikes are always faster.

Wind and human motor for sure are the two biggest factors for 99% of people

Yep

Yep

I have always been told that 'all other things being equal' - the cyclists with the best aero position and efficient cadence /- were fastest against the clock. But the motors are never equal. And hardly anything else .


my current philosophy is - 'all the other things being different', every cyclist who comes home with a smile is the Winner. Regardless of distance, time or conditions. .

^^^Best answer!!!^^^

Wind is number-one, as even a pro rider can be slowed to a crawl or stopped with a strong enough wind. The rider is number two, as a strong rider will go faster compared to other riders in the same conditions. Riding position is a close third, as a really good aero riding position is worth a lot of speed, the more so the higher the speed.

The rest of the factors you listed do not make enough of a difference for anyone but a pro to worry about, unless someone lives in a ridiculously hilly area then a lighter bike can be helpful. The only bikes where the quality would affect efficiency or speed would be ones which are so cheap that 99.999% of cycling enthusiasts will not be regularly riding them, so they are not a factor to consider. The average enthusiast will have some sort of quality bike, and if it is maintained well and the rider is in good shape and rides eight or ten hours each week fast enough to increase their breathing and heart rate, then there is not much more they can do, and there is not much more worth doing at all, unless they are interested in actually racing.

I can go 19mph for a number of miles on level ground with my 50 year-old 35-pound road bike I bought for $3. I can get close to another mph on another old road bike I have which has longer pedal cranks and skinnier high-pressure tires I paid ten-dollars for. And I am sure if I had a $10,000 carbon-fiber aero TT or triathlon bike I could get another mph. But for all the extra money it is not worth pursuing expensive hardware unless you are making a living riding as a pro, or you are so wealthy that buying pro-level bikes is similar to buying a McDonald's cheesburger for the working-class rider.

So if you are an average Joe on a bike of average reasonable quality, don't worry about expensive hardware because you will make the largest gains by far if you are in good shape from riding regularly and have your bike set up so you can get down on the drops in a good aero riding position.

I've always been a proponent of the theory that, "It's the archer, not the bow".

Taking this to riding and here's my influence list. High influence to low influence:

1. human motor
2. wind
3. riding surface
4. bike weight
5. ambient temperature
6. bike type
7. tires
8. quality of components such as wheels & bearings
9. bike age
10. other

As far as personal performance on rides, that's a fickled thing. One day a ride can feel effortless and another day it's a real drama. Diet may have a big influence on performance too.

Wind is the biggest issue by far, assuming the bike is in good working order.
If the bike is not in good working order, then maybe that's the biggest issue...who knows...the level of problem varies too much to know.
Tires are next, I guess. If they are quality fast rolling tires, that will make a huge difference compared to cheap heavy hard wire bead tires.
Age of bike is of no consequence.
Surface is mildly important, but a distant place compared to wind, mechanical condition, or tires.



Can't believe I just answered this hypothetical with very few parameters.