Can somebody explain wheels to me?

Stuster

Hi All

I'm not in the market for any new wheels, rather I've been researching new bikes and despite being completely clueless about bikes in general, I can kind of understand why different frame geometries / materials etc, and also different components make a big difference.

The thing that confuses me is wheels, and why they appear to make such a big difference. In my simple way of looking at things, I'd assume that they all rolled about as well as each other, they were all round, and some just weighed a bit less than others, so different wheels wouldn't make much of a difference?

I know I'm wrong about this, but just aren't sure what it is that I'm missing? What is it that sets different wheelsets apart?

petemadoc

Weight makes a difference in particular when accelerating or going up hills, you have to get those wheels spinning and the lighter they are the easier it is.

Stiffness is also important. When you get out of the saddle and really push hard the wheels start to flex which sucks up some of your energy, if they're stiff then they flex less and you put more of your power onto the road. You can tell if your wheels are flexing under power because they'll scrape the brake pads.

Aerodynamics. Deep section carbon gives you at aero advantage at high speed. Good for time trials, holding high speeds on the flat. Plus they look bling and girls will fall at your feet

General feel and smoothness. Some wheels ride the rough stuff better than others, not sure how you quantify this. Better bearings will roll with less resistance and may be more weather resistant.

In reality its small differences for the average rider I suspect but nice wheels are certainly a big *nice to have*

yeachan153

Rim depth: over 30mm are considered 'aero' and give you advantage of a few mph at high speed

Bearing: smoother bearings mean you free wheel longer and go faster

Rotational mass: Rotational mass is more important then normal mass, eg frame in terms of going faster

Stiffer: stiffer the wheel the less it will flex up a hill or when your powering through, efficient power transfer

racingcondor

The difference between bad and good wheels is that the bad ones will be heavy and flexy. This translates into a bike that feels sluggish, has poor handling through corners and if you are climbing a lot of brake rub that will slow you down.

When you first put good wheels on though you feel like you want to sprint out of every corner, can corner as hard as you like without worrying and can accellerate much better than before.

The reality is probably that neither makes all that much difference to how fast you can go but the speed and confidence you'll feel on the good wheels is one of the easiest improvements you can make to a bike.

All this ignores the benefits of aero wheels which as well as (hopefully) being good wheels will give a small gain on your average and top speed.

derbygrimpeur

Out of curiosity, am I correct in thinking that as aero wheels may be heavier than some non-aero wheels, they may not be a better choice for hilly riding?

keef66

Yes, you're correct. Unless you expect to be climbing at over 20mph you'd be better off with a lighter conventional wheel for climbing.

And when you get to the top, whip the deep section carbon wheels out of the team car for some white-knuckle descending.

huuregeil

Durability/serviceability is the other important factor, both of the build itself and of the hubs/bearings/freewheel.

JamesB

and following up on that if you plan touring , riding away overseas etc a really important point , IMO, is to consider how rideable / fixable they are if a spoke breaks. Some very low spoke count wheels, high tension built, break a spoke and they go so out of true they cannot be used until fixed. A 32 spoke handbuilt though, break a spoke and 1. it can still be used and 2. can be readily fixed.

From my experience over last 5 years road riding, (not racing), heavier wheels are much less `nice` to ride, feel sluggish, harsh, but are probably not that much slower than a lighter `quicker` wheel, it is just a riders perception; all that would change though if used in a race situtation where acceleration is important

markos1963

derbygrimpeur wrote:

Out of curiosity, am I correct in thinking that as aero wheels may be heavier than some non-aero wheels, they may not be a better choice for hilly riding?

Only if you are comparing like for like tyre wise. A wheel made for tubs will be lighter than a clincher wheel. If you want to go aero and stay light then tubs are the way to go(hence their dominance in racing)