halfspeed

There you go.

canam73

Well, obviously that isn't right. I call shenanigans.

Carbonfiberboy 

Here's an odd one: I wore out the rim on our front tandem wheel: CK hub, 14-15 DB spokes, 36H Velocity Deep-V rim. Temporarily replaced it with a wheel off one of my singles: Ultegra hub, 14-15 DB spokes, 32H OpenPro rim. I notice more vibration through the WoundUp carbon fork and alu bars with the temporary wheel. Should be less. I believe spoke tension is the same on the two wheels. The CK hub flanges are 53mm, the Ultegra flanges quite small, whatever they are. I swapped tires, so it's the same tire, running the same pressure.

bgrider

I have seen this guy recently, perhaps it was a link from BF. Regardless he made an important statement in support of his conclusion: that for a given amount of tire deflection, the rim deflection was the same regardless of wheel design. It would be interesting to know exactly how he ran the test so we could decide if we agree with the results. But that won't be necessary because surely someone who knows why this wheel design or that wheel design "feels" better will be along to set the record straight for us!

Enjoy your ride!

rpenmanparker 

Well, of course, this wasn't the study, it was just the conclusions drawn from it. So we know very little. I don't even know who or what this guy is. Intriguing conclusions I have to say. So how do we find out from the details of the study whether the conclusions have merit?

halfspeed

My suspicion is that most perceptions of wheel comfort are autosuggestion. Crossed, thin-wire spokes on a low profile rim look like they should have more give than fat bladed spokes in an aero rim, so that visual perception drives the subjective experience.

Think about it. Any differences in rim deflection that were significant enough to be felt over even tiny differences in tire pressure would almost have to be from a nearly catostrophically poorly built wheel.

The exception here would, of course, be for wider rims since that significantly changes the shape of the tire's cross section. But again, that doesn't come from the suspension within the wheel components. It's a change in the tire.

The tire is the suspension. Not the wheel. No?

link0

The same argument can be given for frame suspension being completely insignificant compared to tire suspension. I believe it's a good argument.

However, the argument doesn't address small high frequency vibrations that may or may not contribute to discomfort.

rpenmanparker 

So is the video saying a Mavic Open Pro rim and a 80mm deep carbon rim flex the same amount in response to the same stress? Wow, that is hard to believe. Actually he only talks about spoke patterns not rim depth, but he implies all wheels flex the same. I dunno! Without the experimental design information and data it is awfully hard to judge the veracity of the claim.

lsberrios1 

From the 4 pairs of wheels I have I can tell you they all feel pretty different. Specially when you go from Alum to Carbon.

pdedes

He was talking about vertical deflection. Lateral deflection is what counts when you are putting plenty of power down.

rpenmanparker 

I agree. I can feel the differences in spoke patterns and rim depths which is weird since I am fairly numb to the "fine print". Lots goes by under me that I can't feel among three different material bikes, but wheel differences I do feel all the time. I think the guy is full of it.

halfspeed

I think he's saying the differences in vertical compliance are insignificant, especially in comparison to tire deflection, while differences in lateral stiffness are significant under power.

libero

One aspect of wheel comfort that these comments are touching on is what was hitting me on my old wheels: speed wobble.
Used to get speed wobble in rare conditions something like this: strong wind from the right rear; pedal with power; get up to speed, around 40kph; sit down again and continue pedalling. Result was a rear wheel wobble. It's been a few years so I may be slightly mis-remembering the exact conditions. But back at the time I could reproduce it in those windy conditions so decided to get rid of those wheels.

FYI that was on Mavic Ksyrium Equipe, a relatively older version. Nary a wobble on my new wheels, now going on 6 years.
New wheels: Mavic CXP-33-Ultegra-DT Competition

As to the original post: speed wobble is not comfortable, and definitely not in your head. But I'm sure it's a special edge case and some people never see it.

3alarmer 

...it honestly never occurred to me that reasonable people felt otherwise.

bgrider

Personally, I dont find what this guy says about verical wheel deflection too hard to believe without knowing the details of his test method. I am a firm believer that tire pressure is a more significant factor to ride comfort, probably more so than frame design. He does point out that there are differences in lateral stiffness with different wheel sets which I agree with.

SHBR

Tire pressure and more importantly the tire design have more influence on ride characteristics then any other component on a bicycle. I have gone back to 26" wheels, the stiffness to weight ratio (acceleration) is noticeably improved, but the 700C wheels coast a bit better.

I'd be shocked if it could be proven that the differences between these two wheel sets is all just placebo effect.

Campag4life

He does say that wheels can vary widely in lateral stiffness but he doesn't say and the reality is, lateral wheel stiffness affects ride quality. Btw its the same with framesets. Two frames, same vertical stiffness, the frame with the greatest lateral stiffness rides harsher. Specialized in fact talks about that with their new Roubaix SL4 compared to the SL3. The SL4 has a noticeably stiffer ride with the same vertical stiffness as the SL3.

Anybody that has owned different wheelsets knows that the wheel itself can make a BIG difference in ride quality. Yes, tire width and pressure matters more. Frame stiffness matters as well of course. But the wheel is clearly part of the equation. In the case of Campy wheels the difference in ride quality between the Fulcrum 5 and Fulcrum 0 is pronounced. The much lighter Fulcrum 0 is a much stiffer wheel. I prefer the less stiff and lower cost Fulcrum 5 when it comes to ride quality. I will say the early Campy Vento wheels were downright 'whippy'. They have since been redesigned and are now stiffer. Vento wheels are still less stiff than Fulcrum 5 wheels for example. On my 29er, I have a set of wheels made by Mavic with 32 spokes. I wanted bombproof wheels and they are. Super stiff rim and high spoke count. The review of the wheels said exactly what they are....super stiff and really telegraph any road disturbances. There are less stiff rim and lower spoke count wheels out there that would ride softer with the same tire and frame combination.

canam73

I'm confused. You're not new here.

Bob Dopolina 

Bob Dopolina 

Mike burrows is a pretty well respected bike geek. Google the guy if you don't know who he is.

In terms of his observations of vertical compliance, if I understand correctly, he is basically saying that there is no difference between wheels of different lacing. Rim depth is not addressed

Maybe I misunderstood him but I don't see how this is possible. I can take an alloy hoop and crush it with my body weight alone (vertically). I can't compress most carbon rims AT ALL using the same method. This would suggest to me a vast difference in vertical compliance based on materials alone

If we restrict the comments to lacing patterns there is a lot of conflicting data already out there.

If we consider his statement in terms of what is perceptible by riders his statement is not unreasonable and may be at the heart of the video.

I feel that we are looking a at brief video clip, addressing a single aspect of wheel construction and drawing too many conclusions from it. Mike Burrows is not a frivolous guy. If he is saying something it does bare consideration.

Campag4life

I'm not frivolous. He is wrong when he says your backside will not feel any difference wheelset to wheelset. He is conflating vertical deflection with ride quality. This is incorrect. When a wheel stops displacing under load vertically, the wheel bends based upon lateral wheel section modulus aka moment of inertia, spoke pattern, spoke count and even wheel flange height and width. He is likely correct that wheels don't vary much in vertical deflection for the simple reason that vertically, the vertical spoke(s) go into compression on the bottom and tension on the top. Spokes are much stronger in tension and don't allow a wheel to displace much vertically...spokes tend to have pretty high tensile strength. What separates different wheelsets is their lateral deflection which you do feel in ride quality. As I stated before, anybody who has ever owned different wheelsets on the same bike can feel a difference in ride quality between them.

canam73

I have. And I don't.

At least not under the circumstance I believe Mr. Burrows is addressing which is what happens in 0 to moderate torque riding.

This is on wheels that vary from 32/32 spoke x3 laced to Mavic CXP12 rims, 24/28 spoke 2x laced to Kinlin XR19, 24/28 spoke 2x laced to Kinlin XC279, 20/24 spoke laced 2x to Yishun 23x50mm and even a set of Shimano 16/20 spoke OEMs.

Yes, on hills and strong accelerations I can feel some differences. But otherwise, wheels with the same tires, rim width and PSI ride the same to me, or at least close enough that I wouldn't know without looking what I was on.

RaleighSport

Anecdotal evidence: My girlfriends christmas present from me was a flatbar road bike with 700c wheels and 23 tires at 100psi, previously my girlfriend had been riding an ATB with 26" wheels 1.5 semi slicks at 60psi.. no questioning etc was needed, she simply came back after this first commute day and flat out told me "The wheels are so much harder, you feel every little bump even little tiny rocks" I think that's a pretty good indicator that there are huge differences between wheelsets in the real world.

halfspeed

You don't think the difference between 38mm tires at 60 psi and 23mm tires at 100psi had something to do with the difference in perception?

canam73

Nice.