What makes a bike quick

[Andywinds]

This may sound like a daft questions as there is no engine, but I've been looking at loads of bikes at all sorts of price ranges.
If you pay a lot as apposed to a few hundred will you be quicker on the climbs as you will be on a lighter bike? What the main differences on the flat say if you wanted to set a quick spring time? Would the same rider on two different bikes see a big difference on a short section?

 

[MikeW-71]

The rider makes the bike quick.

Light weight will help going uphill, frame stiffness will help to transfer power, but ultimately it's up to you.

On the flat there would be almost no difference between two of the same types of bike with the same gearing.

 

[MichaelW2]

If you produce enough force to bend a frame, making the frame stiffer will help transmit your power to the wheels. If you can't flex a frame, then a stiffer frame is not needed.
If you ride very quickly, then aerodynamic drag is significant, and reducing the drag will help you go more quickly. If you cruise along, aerodynamics plays a lesser role.
If you climb big, steep hills, then a lighter bike will let you go a little bit quicker, but on the flat will have little advantage.

"Would the same rider on two different bikes see a big difference on a short section?"
You would more likely see a little difference on long sections.

 

[MikeW-71]

My example, and a some of this is just "feel".

I have two Giant Defys. One is alloy, one is carbon, geometry is the same and the wheelsets are similar.

The alloy bike is great to ride, nimble yet feels a bit "sluggish" (compared to the carbon) when accelerating. Whether that's down to the frame or the cheap FSA chainset I don't know. The carbon bike is even better. More responsive, climbs better (it's nearly 2kg lighter!) and accelerates better. The frame is stiffer, but it's also running a Shimano 105 chainset.

Over a whole ride, I will be a bit quicker on the carbon bike, on the flat at cruising speed, there would be nothing in it. If I then went for a 10 second sprint, the carbon bike would be faster.

 

[midlife]

From a "feeling" point of view (IMHO) the lighter the wheels the faster the bike seems to accelerate / go .....

Shaun

 

[Markymark]

Bike weight saves seconds, fitness saves minutes.

 

[vickster]

Obviously quick is relative, but for me, comfort and enjoyment riding a particular bike. I'll never be fast especially on hills being too heavy and generally crocked, so being as comfortable possible for the duration of the ride is most important - so having a bike that is the correct size and fit is crucial

Closed roads / no traffic helps too!

 

[Shut Up Legs]

Bike weight saves seconds, fitness saves minutes.

Seconds? It depends on the bikes, really. For a while, I rode my 15kg touring bike up a hill not far from where I live, with a climb about 6.75km long and with 300m ascent. After some practice, I managed to get my time down to 21 minutes for the climb. The very first time I timed myself riding up this on my 8kg road bike, I clocked 20 minutes, and I still had some energy left when I reached the end of the climb. Actually, now that I think of it: back then I weighed about 85kg and now I'm 78kg - I should definitely take the road bike over there and give it another shot.

 

[Saluki]

The rider makes the bike quick.
My Planet X is bloody slow and my friend's knackered BSO bloody quick when I ride her bike and she rides mine. I can out sprint her, out climb her and out turn her on the downhills on her argos road bike thingy.
She's not overweight, she runs and does aerobics but can't ride a bike for toffee. Hmmm, maybe I should offer toffee

 

[Deleted member 35268]

AERO seems to be playing more of a part of road bike design of late. Thats not going to help going up, but certainly will coming back down.

 

[cyberknight]

Went out on my commuter with rack+ gaurds on my quick 24 mile loop last night , it weighs maybe 2 kg more unloaded than my nicer bike and i saved uhm maybe 30 seconds on a fairly flat route .
On hills and acceleration it takes more effort but one the flat i cant tell any difference.

 

[cd365]

Legs

 

[Racing roadkill]

The rider.

 

[Tin Pot]

The gradient makes the bike quicker.

 

[Tin Pot]

Bike weight saves seconds, fitness saves minutes.

I saved ten minutes on a 20k loop by buying a new bike.