Which components actually make a difference?

This little gem of a review of a BLB hub
and its "it has almost the same performance as a real track hub" got me thinking: how can you tell? It's a hub. You lace it to a rim, put a sprocket and lockring on it and it goes round. So the question is: which components actually make a substantial, immediate difference to the way a bike performs and which don't? Not components that might save a few grams or make you a couple of seconds faster up Mt. Ventoux or produce an extra couple of watts on your PowerTap. Which components, when improved, actually make a bike feel better then moment you start riding it? Comparisons only of similar condition items please (no comparing rusted old junk with brand new ) and within reasonable limits (no comparing plastic BMX wheels with Zipps). Note that collectability, aesthetics and durability are not factors here, those are all good reasons to spend more; immediate feel and speed are what counts.

List (and argument) time:

Do make a difference:

• Saddle - obvious source of discomfort if you get it wrong
  
• Grips/Bar tape - see saddle
  
  
  
  

Don't make a difference:

• Cranks - they're effectively a metal bar, unless you're a monster even a cheap crank will still get all your power to the chainring)
  
• Chainring and sprocket (for a fixie) - if the chain stays on them the quality makes no difference.
  

speaking to theory swine recently we both praised the quality of da 7600 hubs
they just seem faster roll smoother and i swear make you go faster
whether it is a placebo i don't know and have never tried 2 different types of hubs on the same bikes

but good quality wheels are a good starting point for any build, they are the things that take the hardest beating skids cog strain potholes kerbs
once they've done their work less stresses i would say make it to the other components / frame

Depends what "performance" you are talking about.

Good track hubs will spin with less resistance than cheap road hubs due to lack of seals, better bearings, better machining.

The lack of lube, lack of seals certainly won't 'perform' well in the outdoor durability stakes though will they?

Performance could mean all manner of things, not just going faster. Everything is a compromise anyway.

Legs, Wheels.

tires would be the biggest, then rims, then hubs imo

tires are massive, tyre size and also profile (relating to rims) can affect cornering, contact spot and rolling resistance.

hubs also, i've held good quality hubs and cheap hubs and spun them just holding the axles and pushing the hub body and there is a big differenece in how long they spin, novatec's being the best value if anyone's asking, they spin for almost as long as the expensive ones but are a fraction of the price

My bike doesn't have legs.

You'll get far more 'performance' out of stretching, and lowering your bars than any component.

Buy stuff because its appealing.

Good tyres though. Gotta have decent rubber. Lifes to short for nasty riding cheap tyres.

Depends what "performance" you are talking about.

Good track hubs will spin with less resistance than cheap road hubs due to lack of seals, better bearings, better machining.

The lack of lube, lack of seals certainly won't 'perform' well in the outdoor durability stakes though will they?

Performance could mean all manner of things, not just going faster. Everything is a compromise anyway.

I tried to be quite specific and I said that durability wasn't a consideration (don't fight the hypo!). Everything is a compromise as you say.

I'll put it another way. If you did a properly double-blind test with two identical bikes except for changing one component, changing which components would make you feel an immediate, **substantial **difference in comfort or speed?

tires would be the biggest, then rims, then hubs imo

tires are massive, tyre size and also profile (relating to rims) can affect cornering, contact spot and rolling resistance.

hubs also, i've held good quality hubs and cheap hubs and spun them just holding the axles and pushing the hub body and there is a big differenece in how long they spin, novatec's being the best value if anyone's asking, they spin for almost as long as the expensive ones but are a fraction of the price

I noticed that with a hope hub, but do you actually notice the difference when riding?

Tyres.

You'll get far more 'performance' out of stretching, and lowering your bars than any component.

Unless you lower your bars too far and you're then forced to the side of the road to try and sort the damage. #onlyanidiotwoulddothatthough

I tried to be quite specific and I said that durability wasn't a consideration (don't fight the hypo!). Everything is a compromise as you say.

I'll put it another way. If you did a properly double-blind test with two identical bikes except for changing one component, changing which components would make you feel an immediate, **substantial **difference in comfort or speed?

I think a blind test would cause you to crash before you noticed anything.

For me the answer would be saddle. I would not notice changes in anything other than tyre pressure. Oh and position.

Clipless vs. flat pedals is a pretty obvious difference..

BRAKES for me. Especially when commuting. When I've got good brakes I ride with a lot more confidence. On my old commuter the brakes were the only thing ever worth stealing.

Prob not so relevant though on a fixed gear forum!

I'd say brake pads more than brakes, provided that they're half decent modern dual calipers.

Clipless vs. flat pedals is a pretty obvious difference..

Thats a good one.

Good tyres though. Gotta have decent rubber. Lifes to short for nasty riding cheap tyres.

This in abundance and what most other people have said, good wheels.

Blind test I bet most people couldn't tell the difference between wheels, unless you went from standard wheels to a deep section front or a disc rear or similar where the wind will definitely change the handling very obviously.

hubs also, i've held good quality hubs and cheap hubs and spun them just holding the axles and pushing the hub body and there is a big differenece in how long they spin,

I noticed that with a hope hub, but do you actually notice the difference when riding?

After running a dynamo hub I'm always dubious of the old spin test. The resistance in your hand is huge. On the bike it's noticeable, but not very.

IMO you can feel when wheels are stiffer, and/or lighter, and/or have the appropriate width for your tyre. I don't know if that actually relates to a real performance gain though.

Wheels, especially tyres, and shifters

Tyres, then wheels. Once riding I don't think you could tell the difference between hubs. Saddle, but that depends on position. Good bar tape makes a big difference too. After that it's all incremental. Chainrings and cogs - cheep pressed steel vs proper forged and cnc items add an overall feeling of smoothness imo.

Wheels as in lighter wheels..

hubs also, i've held good quality hubs and cheap hubs and spun them just holding the axles and pushing the hub body and there is a big differenece in how long they spin, novatec's being the best value if anyone's asking, they spin for almost as long as the expensive ones but are a fraction of the price

This test is meaningless, as is spinning a wheel in a wheel jig or in the forks of an upturned bike. This is because bearings behave differently under load.

Skaters will recognise that when you fit your wheels with new, posh bearings and you spin the wheel they come to a stop pretty quick, but put the board on the ground, apply your 70 kilos and gravity, push off and they will fly!

tyres, tubes hav most instant effect and are best bang for buck. OP is wrong about chainrings and sprockets, you'd think it would be easy to produce concentric chainrings and sprockets but cheap ones very often aren't....the contact points in transmission are very important in power transfer, cost is not the only issue, age is factor too. Chains are a good example of this, it's better to fit a £10 chain 6 times a year than fit a £60 chain once a year.