Do wider rims live up to their hype for lighter riders?

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Imaking20
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by Imaking20

Most noticeably; on descents. Wider rims with any 23-25mm tire I've ridden don't "fall over" so much - they give me more consistent feedback as I lean the bike over. From a motorcycling background, this is very valuable to me.

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Zigmeister
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by Zigmeister

Having run, and still own a set of Deep V 50mm carbon clinchers with Conti GP4000s wheels that are 19mm wide approximately at their widest/brake track, and comparing those wheels to ones I run on race day, Zipp 303 FC tubulars with Vittoria Corsa CX tires, the ride is night/day.

The Deep Vs are unstable as you can imagine in xwinds, or any wind for that matter. The Zipp FC, are stable, and you only feel a slight nudge at 45mm depth which they are when the wind is blowing.

Next, the vertical compliance is probably the biggest thing I notice immediately as soon as I hit one single peeble/bump in the road. The Deep V carbon wheels transfer the signal right up through the frame into your bum/hands.

The Zipp FC 303s take the bumps very well, smooth the ride out, and take the sting out of the hands/bum.

I run a Scott Foil Team edition by the way, it doesn't get any stiffer than that ride. So the effects are really noticeable on this frame between a Deep-V 50mm and the Zipp FC 303 Tubular 45mm.

I weight 163-168lbs and 5'11".

I also had 2 other frames before my Scott foil, the ride was identical what I described above. The other frames weren't as stiff as the Foil, but the ride difference between a deep V carbon and a wide profile was significant and I love the wide profile personally.

fdegrove
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by fdegrove

Hi,

Imaking20 wrote:Most noticeably; on descents. Wider rims with any 23-25mm tire I've ridden don't "fall over" so much - they give me more consistent feedback as I lean the bike over. From a motorcycling background, this is very valuable to me.


If your previous combination of tyre/rim gave you that impression I'd be inclined to point the finger at too high tyre pressure. Naturally wider rims combined with wider tyres won't give you a feeling of tipping over from one edge to another. It will tend to squirm which really gives me a creepy feeling.
In reality this so called problem only exists in the head of the rider though.

Key to speed is having the right amount of compliance for a given road surface. That, in turn will depend on yet another set of factors such as load and how well it can be modulated and how lossy it is or not.
Adjusting compliance to the level of training of the athlete is yet another factor. Endlesss....

Nothing ever is black or white, everything is yet another shade of the same grey.

Ciao,
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kulivontot
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by kulivontot

Not to knock your review, but comparing rando 50mm CC to zipp 303 FC is not real indicative of a change in rim width. Yes there is a difference between those wheels but also another dozen other changes that could account for that. Even old 303 vs 303 FC is hard to say is 100% due to the rim width as opposed to the overall shape and carbon layup changes.

kulivontot
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by kulivontot

Nm, reread that. You've got tubulars. Does rim width even matter for tubs from a ride comfort/handling perspective?

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WMW
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by WMW

Imaking20 wrote:Most noticeably; on descents. Wider rims with any 23-25mm tire I've ridden don't "fall over" so much - they give me more consistent feedback as I lean the bike over. From a motorcycling background, this is very valuable to me.


In my experiences of charging down technical descents, I don't feel these tiny 100psi tires flopping around. I'm pretty amazed that anyone could. Are your roads super-smooth? Because what I'm worried about in corners is bumps, cracks, rocks, sand, etc.

A road racing motorcycle is a totally different deal. On most courses cornering speed and traction are everything. So you run fat rubber and wheels and low pressure. You have a massive engine on tap to deal with any drag or weight increase...
formerly rruff...

Zigmeister
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by Zigmeister

kulivontot wrote:Not to knock your review, but comparing rando 50mm CC to zipp 303 FC is not real indicative of a change in rim width. Yes there is a difference between those wheels but also another dozen other changes that could account for that. Even old 303 vs 303 FC is hard to say is 100% due to the rim width as opposed to the overall shape and carbon layup changes.


If you have watched zipps slow motion video of the FC shape and how it flexes over bumps due to the wide rim design, and compare that to a narrow v design, it is obvious what is happening and why the ride is so much better on a wide rim like zipp FC, Bont Aeolus D3 etc...

Tubular helps, but the physics and design of a deep v transmits the impact from the v point right up vertically through the hubs, fork headset, seat stays etc...there is no sidewall flex really.

The FC design the rim flexes outward during impacts taking the vibration and force transmission and dampens it. It is why Boonen loved the rims when he won all his classics last year, and rides them exclusively for the classics and cobbles this year.

Cancellera of course is running the new Shimano test wide wheels to great success, and no flats either, like Bonnen during Roubaix. I think it speaks highly of the ride quality and wide design as being reliable and proven even over bad surfaces now. Not that other wheels wont flat, or a Zipp will not get a flat either. Luck is part of it during the classics.

Call it anectodal, that is how cycling and comparisons are. But, ride both wheels, it is obviously within 1 mile how much better the Zipp FC wide design is to any regular deep v carbon wheel.

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743power
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by 743power

Boonen is riding 2010-2011 303s with firecrest logos still afaik. The fcs don't play we'll with the clearances on that sl4. But yes, same "suspension" effect on those rims. And Fabs is on bontragers, not shimano.
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fdegrove
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by fdegrove

Hi,

kulivontot wrote:Nm, reread that. You've got tubulars. Does rim width even matter for tubs from a ride comfort/handling perspective?


What applies to clinchers applies to tubular tyres as well but to a slightly less pronounced extent. Whilst I do not feel a wider rim would benefit a tubular as such, a wider rim may well introduce a bit more vertical flex depending on yet another set of factors.

If you'd ask if a wider than traditional tyre as in + 23mm would benefit from a rim width and shape that is optimised for it in every respect, then yes. It will still take some thinking to know how and when to use it though.

Point is, one should not generalise but specialise.

Ciao, ;)
Being a snob is an expensive hobby.

Imaking20
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by Imaking20

fdegrove wrote:Hi,

Imaking20 wrote:Most noticeably; on descents. Wider rims with any 23-25mm tire I've ridden don't "fall over" so much - they give me more consistent feedback as I lean the bike over. From a motorcycling background, this is very valuable to me.


If your previous combination of tyre/rim gave you that impression I'd be inclined to point the finger at too high tyre pressure. Naturally wider rims combined with wider tyres won't give you a feeling of tipping over from one edge to another. It will tend to squirm which really gives me a creepy feeling.
In reality this so called problem only exists in the head of the rider though.

Key to speed is having the right amount of compliance for a given road surface. That, in turn will depend on yet another set of factors such as load and how well it can be modulated and how lossy it is or not.
Adjusting compliance to the level of training of the athlete is yet another factor. Endlesss....

Nothing ever is black or white, everything is yet another shade of the same grey.

Ciao,


100psi and I was weighing just over 77kg. I wouldn't think that pressure is too high. Maybe you misunderstood me though - the tipping/falling sensation for me is more on narrower rims and not so apparent with wider rims.

WMW wrote:
Imaking20 wrote:Most noticeably; on descents. Wider rims with any 23-25mm tire I've ridden don't "fall over" so much - they give me more consistent feedback as I lean the bike over. From a motorcycling background, this is very valuable to me.


In my experiences of charging down technical descents, I don't feel these tiny 100psi tires flopping around. I'm pretty amazed that anyone could. Are your roads super-smooth? Because what I'm worried about in corners is bumps, cracks, rocks, sand, etc.

A road racing motorcycle is a totally different deal. On most courses cornering speed and traction are everything. So you run fat rubber and wheels and low pressure. You have a massive engine on tap to deal with any drag or weight increase...


Some descents around here are like glass and some feel like they'd be better suited on a MTB.

My first priority is line selection. If your focus is on debris it's less likely you'll have attention to spare for how your tires are reacting.

On a motorcycle; yes your tires are larger and pressures are lower - but you're also on a 400+ lb machine - I'd say a parallel can be made regarding the sensation of grip or lack thereof. Part of learning to go fast around the track on a motorcycle is learning when your tires let go, how to react to it, and if/how it affects your outcome. Slipping is part of the game.

I pay that same attention to my tires on a bicycle - maybe it's force of habit. Of course, the "squish" isn't there on a bicycle because of the much higher pressures but the loss of traction can absolutely be there - and not all slipping means catastrophe.

Sorry for the tangent.

My opinion still stands that a wider rim transitions more smoothly than a narrower one with the same size tire. This isn't a result I sought out when going to wider rims (I just wanted to run lower pressure) but the most lasting effect I've gotten from the switch is handling.

fdegrove
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by fdegrove

Hi,

Maybe you misunderstood me though - the tipping/falling sensation for me is more on narrower rims and not so apparent with wider rims.


Actually, I think I know what you mean although I only get that kind of sensation when using narrow (20mm) tubulars at relatively high pressure (9 bar) going into a tight turn. The same rim with a wider (22mm or higher) tubular at 8 bar won't give that sensation.

I think a clincher/ tubeless rim would benefit from a wider rim, a tubular rim much less so if at all. Both may well give a sense of a higher degree of comfort though.

Ciao, ;)
Last edited by fdegrove on Tue Apr 09, 2013 12:56 pm, edited 1 time in total.
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Imaking20
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by Imaking20

I agree completely! My mistake for not clarifying that I was referring to clinchers exclusively.

joshvoulters
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by joshvoulters

Imaking20 wrote:Most noticeably; on descents. Wider rims with any 23-25mm tire I've ridden don't "fall over" so much - they give me more consistent feedback as I lean the bike over. From a motorcycling background, this is very valuable to me.


This is spot on, based on my experience (Archetypes w/ Veloflex Corsas)

Cornering feels more progressive than on narrower rims, especially when leaning into a fast turn. Great for confidence in a crit or on a quick descent.

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