NEW WHEELS

Bicycle related chatter & discussion
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FAswad
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Postby FAswad » 18 May 2008, 13:30

Their birth has been more complicated than genetic engineering, but, they're here now.

Build info and photos:

Rims
Kinlin XR-300 (aka Niobium 30)
Depth: 30mm
Weight: 462g rear, 472g front

Hubs
White Industries H2 (oh so sweet).

Spokes
DT competition (2.0/1.8/2.0)

Front build
Lacing: Radial
Weight: 690g

Rear Build
Lacing: 3 cross
Weight: 895g

Built by Tony Marsh of Engadine Cycles

Photos

Image
Rear

Image
Front

Image
Front

Image
Rear hub

Image
Front hub (They must have stuffed this with butter! I pick up the wheel from either axle ends and the wheel starts to rotate willy-nilly!)

Image
3X lacing

Image
Radial lacing

Image
Kick-azz skewer

Come on Huw. Show us yours.
Last edited by FAswad on 18 May 2008, 19:44, edited 1 time in total.

Eugen Schilter
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Postby Eugen Schilter » 18 May 2008, 18:32

Fuad,
I think you have to go back and pay extra .. I see 3x crossed lacing on both sides rear wheel!
On the front wheel, what is the reason to have the spokes coming from in between the hub flanges (spokes' heads outside). My religion teaches they should be coming from the outside as this gives substantialy increased lateral wheel stiffness and strength. Is it better looks, easier to clean?

Did the mech predict that the wheel will have to undergo re-truing after some kms? I suspect it will. Is there lock-tight in the nipple thread? and if yes what about the undue spoke twisting when truing?

:?: : does anybody know a quick way to find the optimal spoke length (given a hub a rim and the lacing pattern)? :?: I know only trial and error and it is a very time consuming exercise.

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Huw
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Postby Huw » 18 May 2008, 18:55

Very nice Fouad! I'd love to show you mine . . . but they're still in pieces. I'll post them when I can.

How do they ride?


Eugen, there are a range of spoke length calculators on the net - just type in "spoke length calculator" to Google and you can choose from the many independent or company-produced calculators. A calculator will ask you all the questions it needs to determine optimal spoke length for a given lacing pattern.

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Huw
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Postby Huw » 18 May 2008, 18:58

Wow - they turned out lighter than I thought, too.

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FAswad
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Postby FAswad » 18 May 2008, 19:33

I guess you are right on the rear wheel lacing. I didn't even think about it and assumed that was what he did. But I guess its all the same and they are stronger this way so no probs.

With the front, all i said was that I wanted them radial. I did not specify orientation. having said that, I guess there are advantages and disadvantages for both. I have read that inward makes the wheel stiffer laterally and means the spokes have to endure less tension. Outwards makes the whell a bit more aero and relieves tension from the hub flange. I guess the differences are minute and as it is on a front wheel, hopefully it would be fine. The beauty of hand built wheels is that you can play around with them if you find they are not doing the job. Thats partly why I went down this road.

Otherwise, you ask too much of me. I have no idea whether locktite was used or not, or whether the wheels will need a retrue or not. I guess the fact that my current wheels, built by the same person, have been BOMB-PROOF has made me trust him blindly. Let us see how it all turns out. I will let you know if I run into trouble.
Fuad,
I think you have to go back and pay extra .. I see 3x crossed lacing on both sides rear wheel!
On the front wheel, what is the reason to have the spokes coming from in between the hub flanges (spokes' heads outside). My religion teaches they should be coming from the outside as this gives substantialy increased lateral wheel stiffness and strength. Is it better looks, easier to clean?

Did the mech predict that the wheel will have to undergo re-truing after some kms? I suspect it will. Is there lock-tight in the nipple thread? and if yes what about the undue spoke twisting when truing?

:?: : does anybody know a quick way to find the optimal spoke length (given a hub a rim and the lacing pattern)? :?: I know only trial and error and it is a very time consuming exercise.

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T-Bone
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Postby T-Bone » 18 May 2008, 19:43

Very Nice!!!! Is the H2 freewheel nice and noisy like the H1??? Love the whirl i get when freewheeling.

As Eugen said, heads in should give a stiffer wheel, but they look good anyway. I'm assuming you went for the DT comps for some extra strength, though i would probably have gone with DT revolutions, however my wheels don't have to hold as much weight.

I have to decide between the H2 and Dura-Ace hubs for some carbon wheels i want, but i'll have a little time to think it through, and i can't afford most other nice hubs (tune, DT), but there might be a new choice available for me. Though with the rims costing $750 each i have to make sure i get the most i can from them.

As for spoke length calculators, i use spokecalc or the calculator on the DT website, though i'm sure most others work fine too. Here's the spokecalc link http://www.sheldonbrown.com/rinard/spocalc.htm

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FAswad
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Postby FAswad » 18 May 2008, 20:54

The H2 freewheel is noisy. I am not familiar with with the H1 whirl, so i cannot say how the H2s compare. But they sure do have a loud whiz to them.

Yes. I tried not to gamble too much on spokes. Already, there is the front radial, and Eugene's post has already got me thinking! My other option would have been something like Sapim CX-Rays or the DT Aerolite. These would have given me the best of all worlds in aerodynamics, weight and stiffness. But for the price (extra $200), I decided it was not worth it.

I have really grown to like those H2s. For your purposes, I guess they are lighter than the Dura-Ace hubs at a comparable price. Also remember that these hubs are good for radial lacing wheras the Dura-Ace will not take radial. Tunes would have been great, but the price was prohibitive. I guess this combination is hopefully perfect one for me.
Very Nice!!!! Is the H2 freewheel nice and noisy like the H1??? Love the whirl i get when freewheeling.

As Eugen said, heads in should give a stiffer wheel, but they look good anyway. I'm assuming you went for the DT comps for some extra strength, though i would probably have gone with DT revolutions, however my wheels don't have to hold as much weight.

I have to decide between the H2 and Dura-Ace hubs for some carbon wheels i want, but i'll have a little time to think it through, and i can't afford most other nice hubs (tune, DT), but there might be a new choice available for me. Though with the rims costing $750 each i have to make sure i get the most i can from them.

As for spoke length calculators, i use spokecalc or the calculator on the DT website, though i'm sure most others work fine too. Here's the spokecalc link http://www.sheldonbrown.com/rinard/spocalc.htm

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FAswad
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Postby FAswad » 18 May 2008, 20:58

I know. Just teasing.

Will let you know tomorrow how they ride. They better get up and help me pedal. Otherwise, they're going back to where they cam from!
Very nice Fouad! I'd love to show you mine . . . but they're still in pieces. I'll post them when I can.

How do they ride?


Eugen, there are a range of spoke length calculators on the net - just type in "spoke length calculator" to Google and you can choose from the many independent or company-produced calculators. A calculator will ask you all the questions it needs to determine optimal spoke length for a given lacing pattern.

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T-Bone
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Postby T-Bone » 18 May 2008, 21:15

We can compare the freewheel noise at the ken dinnerville on sunday, but from what you've said they sound similar.

I wasn't aware of Dura-Ace hubs not being suitable for radial lacing, i'll have to look into it a bit more. The H2's are probably a good choice otherwise, but there's another i need to look into again, not sure if they're out yet, and can't remember exactly who's making them.

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FAswad
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Postby FAswad » 18 May 2008, 21:22

Actually Dura-Ace are suitable for radial lacing. Sorry for the miss-information. I got confused because "some" shimano hubs are not suitable

Here, have a look: http://techdocs.shimano.com/media/techd ... 611787.pdf

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T-Bone
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Postby T-Bone » 18 May 2008, 22:30

Thanks for finding that, i thought they should be fine, though i wouldn't be lacing anything over 20holes radial, so i'd suspect the hubs would hold up anyway, though i know DT have specific radial versions of their front hubs. I've got some time to consider everything anyway.

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mikesbytes
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Postby mikesbytes » 19 May 2008, 13:05

So how do you feel when riding on the new wheels?

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FAswad
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Postby FAswad » 19 May 2008, 20:51

I took the new wheels on a 40km dash on rolling terrain this morning. And here are the results:

No difference felt in getting up the short hills. Realistically, it would be tall order given that the reduction in weight is 400g in a 102kk system (bike and rider). There might have been a difference but I could not feel it.

Accdeleration from stationary position and slow speeds felt easier. But thats quite subjective I guess.

On the flats and downhills, the difference was more pronounced. Where I used to do 60km/h, I was hitting 62-64km/h. But with, different tyres, hubs, rims, spokes, and enthusiasm, this could have been any of those.

Appart from that, I could feel a bit more feedback from the road , which suggests I might need to back of tyre pressure a bit.

All in all, I am satisfied. They hopefully serve the purpose that I meant for them, which is to have a new, shiny, relaible set of wheels that would not fail when I need them not to because I have put 16,000km on them.

So my advice to anyone thinking of investing in new wheels (or any other equipment) is this: If you are expecting drastic improvements in performance save your money and save yourself the heartache. New equipment is for drooling over, speed is in the legs and lungs.
How do they ride?
So how do you feel when riding on the new wheels?

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mikesbytes
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Postby mikesbytes » 19 May 2008, 21:18

So they made you feel good?

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weiyun
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Postby weiyun » 19 May 2008, 21:48

Wow, very nice! It was very long in the making...

Good that you now have more incentives to train your lungs and legs. So it will make you faster in due course! :lol:

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FAswad
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Postby FAswad » 20 May 2008, 13:23

I like them.
So they made you feel good?

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micklan
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Postby micklan » 20 May 2008, 13:49

I like them.
even though it's a silver hub this is gold:

"Front hub (They must have stuffed this with butter! I pick up the wheel from either axle ends and the wheel starts to rotate willy-nilly!)"

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FAswad
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Postby FAswad » 20 May 2008, 20:54

For those interested in wind tunnel testing and wheel aerodynamics, this might be interesting:

http://rouesartisanales.over-blog.com/a ... 05311.html

Interstingly, all Shimano wheels, down to the entry level RH-550 test much better than the entire Mavic's line (excluding the Cosmic Carbons offcourse).

The other intersting thing stated in the conclusion is that, for front wheels (note this is a study of front wheels only):
"Indeed, the front wheels have perfectly balanced and wide bracing angles, meaning a high lateral stiffness. Reducing the spoke count of the front wheel is not really a problem at all!"

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mikesbytes
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Postby mikesbytes » 20 May 2008, 22:40

If I've understood those graphs correctly, it seems that aero is more important than inertia.

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Toff
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Postby Toff » 21 May 2008, 13:27

If I've understood those graphs correctly, it seems that aero is more important than inertia.
Not necessarily, Mike. For example, when riding at lower speeds on an uneven or bumpy surface you would find that with heavier wheels the ride would be smoother, and less effort would be required to sustain speed.

In most conditions, however, the inertia factor is quite minor. The saving in watts in the example given in the article (between the best wheel and the 4th heaviest wheel) was 7 watts. That's not very much. For comparison, when engineers are designing cooling systems for buildings, they typically estimate that the average person radiates roughly 100 watts into the room just sitting there. A saving of 3-7 watts would really only make a difference when an athlete is at the margin of elite competition...

Wind resistance on the other hand increases proportionately with the square of the speed at which you are travelling, so a small increase in speed can result in a substantial increase in drag. Unless you are competing in Team sprints, or Kilos on the track (where sudden accelerations from a standing start is important), I don't see much need to worry about inertia over aerodynamics.

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mikesbytes
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Postby mikesbytes » 21 May 2008, 14:11

What is the difference between 40kph and the 50kph that the tests were done at?

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FAswad
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Postby FAswad » 22 May 2008, 09:03

What is the difference between 40kph and the 50kph that the tests were done at?
As Toff said: "Wind resistance on the other hand increases proportionately with the square of the speed at which you are travelling, so a small increase in speed can result in a substantial increase in drag."

That means at 50kph, drag is significantly higher.

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micklan
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Postby micklan » 22 May 2008, 09:40

As Toff said: "Wind resistance on the other hand increases proportionately with the square of the speed at which you are travelling, so a small increase in speed can result in a substantial increase in drag."

That means at 50kph, drag is significantly higher.
So if the drag increases then the payoff is greater in a peleton of riders, the more riders then higher drag, thus a longer drag pocket?

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Toff
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Postby Toff » 22 May 2008, 09:54

As Toff said: "Wind resistance on the other hand increases proportionately with the square of the speed at which you are travelling, so a small increase in speed can result in a substantial increase in drag."

That means at 50kph, drag is significantly higher.
The force required to overcome wind resistance increases parabolically with speed. Graphically, it looks like you are trying to force your way through a brick wall as speed increases.

Here is the best graph I could find to explain:
Image
I know it plots power against velocity, but the relationship between power and force is linear so it shouldn't matter. What you will notice is that at 50k/h we're already off the top of the graph.

Most of the force the rider is trying to overcome does not come from aerodynamic drag on the wheels, but drag on the rider. This means that you can increase your top speed, and drastically reduce your effort at all speeds (but especially high speeds) by making your riding position more aerodynamic, rather than buying ultra-light, or ultra-aero racing wheels...
Image
Here is the "Gold Rush" bike if you're interested...
Image
Nice wheels by the way, Fred... Reminiscient of the rare 1982 Campy Record Hi-Lo flange hubs developed for the West German Olympic team. I would have thought that the narrow spoke spread on the back would result in extra wheel flex though. Any observations?

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williamd
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Postby williamd » 22 May 2008, 13:07

The bat cycle is nearly as good as the gold rush.

I wonder if I could use it in the Dinnerville

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mikesbytes
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Postby mikesbytes » 22 May 2008, 14:02

Looking at those figures, its something like double the number of watts to ride at 50kph vs 40kph

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Huw
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Postby Huw » 01 Jun 2008, 14:35

My new new wheels.

I recently got some new wheels (7850 Dura-Ace hubs, 28 h fr, 32 h rear, Mavic CXP33 rims, DT Swiss double-butted 14/15 g spokes). They're silky smooth and awesome.

But now, Fouad and I've got even newer wheels! Mine were built by Lindsay. 27 mm KinLin niobium alloy rims, White Industries H2 hubs (20 h fr, 28 h rear, Sapim straight-gauge spokes). Here they are:

Image
Image
Image
Image

I was going to take these babies out on their initiation run this morning to Waterfall, but it was too wet for my delicate constitution. I spent my time instead thinking about how I might pimp the wheels. They're no deep profile carbon roarers, but they're pretty hot just the same. I thought they needed some decal action, like this:
Image

Then, a little later, I thought about this:
Image
Apologies to Lindsay.

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Simon Llewellyn
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Postby Simon Llewellyn » 01 Jun 2008, 14:51

I recon the munky biznez is the goer!!! But why did you invest in two sets of wheels so close together? training & racing? racing and touring? security of having second set of wheels?

I would of thought either set would have done the job? I was doing abit of bike seeing at sydney roads yesterday to see what everybody else is using and the low profile alloy dura-ace clinchers were pretty popular. Mavic deep carbon were probably the most common wheels in combination of tubulur or clincher. Then of course campag wheels were plentiful.

How do the white industry hubs rate to dura-ace?

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Huw
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Postby Huw » 01 Jun 2008, 16:10

But why did you invest in two sets of wheels so close together? training & racing? racing and touring? security of having second set of wheels?

I would of thought either set would have done the job?

How do the white industry hubs rate to dura-ace?
It's a long story, but I've tried to capture the 8 most pivotal moments below:
1. I wanted a set of race wheels
2. I ordered the parts (niobium rims and WI hubs, for wheels #2)
3. Niobium rims were damaged
4. I broke the original wheels #1
5. I realised I actually had NO working wheels and experienced an existential crisis as I wandered the wheel wilderness
6. I went crazy and ordered a nice set of Mavic/DA wheels for training/racing (wheels #3)
7. Trek suddenly decided to replace my whole rear wheel, meaning I had my original wheels #1 back in order
8. Fouad and I finally got our replacement niobium rims, and Lindsay built my wheels #2.
(I don't know if the numbers help, but I now have 3 sets of wheels. In part it was accident - I didn't think Trek would replace the rear wheel, since I'd given it a good hammering over the last 3 years, so that sparked me to get the Mavic/DA wheels).

Yes, both the Mavic/DA and Niobium/WI wheels are great race wheels. Niobium/WI slightly lighter, Mavic/DA probably sturdier.

DA have traditional cup-and-cone bearings and hubs are slightly heavier (267 g) than White Industries (cartridge bearings, 252 g some of the absolute lightest in the market). Both are forged, both with Ti freehubs. WI makes a racket, DA much less noisy. DA has very fine pawl position. WI rear has larger diameter drive-side spoke flange, DA same diameter on both. Both appear to roll like buttered K-Y jelly on a hot day in Greece.

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FAswad
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Postby FAswad » 02 Jun 2008, 12:20

AMEN
Both appear to roll like buttered K-Y jelly on a hot day in Greece.

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mikesbytes
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Postby mikesbytes » 02 Jun 2008, 13:50

3 sets of wheels Huw.

Why don't you go tubeless for the racing set.

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Huw
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Postby Huw » 03 Jun 2008, 12:49

Why don't you go tubeless for the racing set.
Singles? Frankly, they sound like hassle I could do without. On road, my opinion is leave singles to the pros (and their mechanics, soigneurs and sponsors).

I accept that singles would confer a weight advantage. I'm dubious however about the benefit of adding increased pressure to road tyres. As I keep being reminded, comfort is still a major factor for me in road races. Racing on even harder tyres would further add to stress on the body. I reckon this would quickly negate any benefits due to reduction in rolling resistance. Finally, they're expensive, and need to be replaced after a puncture.

Thoughts? I believe Simon has just ordered a nice set of Dura-Ace deep-profile carbon singles. But I know that high inflation pressures and discomfort are important to him :lol: .

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mikesbytes
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Postby mikesbytes » 03 Jun 2008, 12:51

Not Singles, tubeless clinchers

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Huw
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Postby Huw » 03 Jun 2008, 12:55

Not Singles, tubeless clinchers
Y'know, the thought never crossed my mind.

Seems like one would be buying oneself into a monopoly with tubeless. The tyres are more expensive (and heavier - though it's claimed lighter overall, I realise). I've heard there are benefits in that they can be run at lower pressures (don't suffer from pinch-flats) - but wouldn't this increase rolling resistance?

Perhaps I'm just a technophobe?

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T-Bone
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Postby T-Bone » 03 Jun 2008, 15:55

If i was ever going to go for tubeless, it'd only be once there has been sufficient development and known benefits. At the moment i see none.

I will be going for some tubular race only wheels, hopefully later this year, maybe early next. Nice 68mm deep carbon rims (made by EDGE), dura-ace or white industries hubs. The new 7900 dura-ace hubs seem good, especially doing away with cone wrenches, for bearing adjustment. I won't be running tire pressures any higher than i am now though.

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Simon Llewellyn
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Postby Simon Llewellyn » 03 Jun 2008, 16:01

Singles? Frankly, they sound like hassle I could do without. On road, my opinion is leave singles to the pros (and their mechanics, soigneurs and sponsors).

I accept that singles would confer a weight advantage. I'm dubious however about the benefit of adding increased pressure to road tyres. As I keep being reminded, comfort is still a major factor for me in road races. Racing on even harder tyres would further add to stress on the body. I reckon this would quickly negate any benefits due to reduction in rolling resistance. Finally, they're expensive, and need to be replaced after a puncture.

Thoughts? I believe Simon has just ordered a nice set of Dura-Ace deep-profile carbon singles. But I know that high inflation pressures and discomfort are important to him :lol: .
I did my research on sigles and all s ... uncture...

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Postby weiyun » 03 Jun 2008, 16:07

In terms of tyre pressure I haven't pumped wheel to less than 140psi in the last year or two, track or road. It was uncomfortable at first but 160psi on the track was so fast that I got used to it very quickly and anything less than 140psi now just feels like I have a puncture...
Was that speed difference felt or measured?

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Simon Llewellyn
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Postby Simon Llewellyn » 03 Jun 2008, 16:18

Measured in time trials the racing wheels are noticably quicker compared to the training wheels, but in terms of PSI it may be marginally quicker? In my head it is alot quicker and it increases my racing intensity massivelly. When the bike feels like a racing bike I feel like racing!

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weiyun
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Postby weiyun » 03 Jun 2008, 17:08

In my head it is alot quicker and it increases my racing intensity massivelly. When the bike feels like a racing bike I feel like racing!
Maybe we should clock you on that one. ;)

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mikesbytes
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Postby mikesbytes » 03 Jun 2008, 20:04

Y'know, the thought never crossed my mind.

Seems like one would be buying oneself into a monopoly with tubeless. The tyres are more expensive (and heavier - though it's claimed lighter overall, I realise). I've heard there are benefits in that they can be run at lower pressures (don't suffer from pinch-flats) - but wouldn't this increase rolling resistance?

Perhaps I'm just a technophobe?
They provide lower rolling resistance because you don't have a tube rubbing against a tyre.

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Huw
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Postby Huw » 04 Jun 2008, 23:32

They provide lower rolling resistance because you don't have a tube rubbing against a tyre.
But if the tyres are softer, you're also forcing the rubber around more lumps in the road, whereas harder tyres don't mould to the surface so much?

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weiyun
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Postby weiyun » 05 Jun 2008, 02:28

But if the tyres are softer, you're also forcing the rubber around more lumps in the road, whereas harder tyres don't mould to the surface so much?
Thereby gaining better grip while harder tyres bounce around and loses grip in the micro sense, leading to energy and speed loss.

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Simon Llewellyn
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Postby Simon Llewellyn » 05 Jun 2008, 10:42

Guys I"ve just got to say my tubular tyres and cassette for my new wheels arrived yesterday & they are HOT!!!! The one piece unit is just so much more classy than the tyre, tube combination. The fact the pressure starts at 120psi and ranges up to 200psi is truly beautiful. & in truth they are a very solid unit, they look very fast, pure racing.

Now I just wait for the wheels to arrive from Japan and I will be cruising at opens!!!!

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T-Bone
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Postby T-Bone » 05 Jun 2008, 13:39

What tyres did you get? I'm guessing you stuck with Ultegra for the cassette, nothing fancy.

One advantage i can see with the higher pressures in Tubulars is that generally the casing is more flexible and the tire more round when compared to a clincher, so the same pressure in a clincher will not act the same as in a tubular, meaning higher pressures can provide similar comfort with Tubulars.

That's purely guess work though.

Can't wait to see the new wheels, my carbon wheels will have to wait until a bit later in the year, but i'm not sure if they'll make it before Grafton (probably not). So in that case, they might wait until early next year.

Luckily, i've got most of the bits for some wheels waiting to be built, just need nipples. They'll be Campagnolo Omega V rims, DT revolution Spokes, Dura-Ace rear hub, and American Classic Front. Both 28h, front 2-cross, rear 3-cross (spoke lengths that were in stock). I've also got a Shimano DH-3N80 dynamo hub to build, just need to get a velocity aerohead rim, from memory i'll be going with 3cross using DT competition spokes (i've got the spokes, just can't remember what lacing i measured for)

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Simon Llewellyn
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Postby Simon Llewellyn » 05 Jun 2008, 13:47

I actually got dura ace 11-23 cassette. I though about it and decided dura ace wheels should have a dura cassette. it's only fair and the extra bit of weight reduction will be good for racing as they are a racing only wheel.

I ended up getting 2 sets of Vittoria Evo Corsa CX tyres in red. I was after conti competition 22mm but was too slow to order them so decided that the vittorias will do the job for the mean time. They should be a very nice racing wheel. They aren't exactly the cheapest wheels I've ever bought but not the most exensive either....

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T-Bone
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Postby T-Bone » 05 Jun 2008, 14:19

Good to see you're thinking about some weight reduction to conteract those bars of yours. I've got Dura-Ace on my racing wheels for the same reason, Ultegra cassette for Training, and i'll be getting a 105 cassette for my Indoor trainer wheel, so i can move the cassette off there to the new wheels.

Let me know what the Vittorias are like. My plans for Tubulars are currently Veloflex Carbon, followed by Conti Competition, then possibly GP4000. Then again, whatever i buy will most likel be unable to be compared for several years.

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Simon Llewellyn
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Postby Simon Llewellyn » 05 Jun 2008, 16:27

Good to see you're thinking about some weight reduction to conteract those bars of yours.
The bars aren't particularly heavy, they're alloy & the perfect shape. You can't beat cinelli criteriums for racing!!!

Kieran
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Postby Kieran » 08 Jun 2008, 19:29

Here is the best graph I could find to explain:
Image
I know it plots power against velocity, but the relationship between power and force is linear so it shouldn't matter. What you will notice is that at 50k/h we're already off the top of the graph.

Actually power= force*velocity, as force(drag) is proportional to velocity squared, power to overcome wind resistance is velocity squared.

Mike, to go from 40k to 50k you need (50*50*50)/ (40*40*40) times as much power, if wind resistance is the only component. The answer is 1.953 times as much power. Very close to your observed 2 times!

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mikesbytes
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Postby mikesbytes » 08 Jun 2008, 20:58

Thanks Kieran.

What I'm gathering is that my legs put out about 250w for a one hour duration.

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weiyun
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Postby weiyun » 08 Jun 2008, 21:55

What I'm gathering is that my legs put out about 250w for a one hour duration.
There's too much error to try to extrapolate your power performance using a theoretical chart.

Get on a calibrated stationary bike and work on it for an hour and see what's the best power level you can managed for that duration. If 60mins is too long, there's a method to extrapolate it using 20mins data.

Kieran
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Postby Kieran » 11 Jun 2008, 15:52

I have banged on about this before, but the Conti Competitions are excellent tires. The newer ones with vectran liners last longer than the onld grey ones and are even better at puncture resistance.

There is only one time I have gotten a flat on competition tyre that was not due to be thrown out, and that was because of a piece of sharpt metal inside the boot of a car going through the sidewall.

Besides being indestructable, the 22's in particular have a good feel and grip.

Good to see you're thinking about some weight reduction to conteract those bars of yours. I've got Dura-Ace on my racing wheels for the same reason, Ultegra cassette for Training, and i'll be getting a 105 cassette for my Indoor trainer wheel, so i can move the cassette off there to the new wheels.

Let me know what the Vittorias are like. My plans for Tubulars are currently Veloflex Carbon, followed by Conti Competition, then possibly GP4000. Then again, whatever i buy will most likel be unable to be compared for several years.

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Simon Llewellyn
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Postby Simon Llewellyn » 13 Jun 2008, 21:07

Need friends?

Image

You'll have to take your number out of the ph. book. 140psi minimum!!!!

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mikesbytes
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Postby mikesbytes » 13 Jun 2008, 21:17

Thought you were getting Shinmao's

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Simon Llewellyn
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Postby Simon Llewellyn » 13 Jun 2008, 22:10

Tim's new track wheels. 'Pista.'


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