Stiff alloy tubular wheelset for climbs?

Everything about building wheels, glueing tubs, etc.
User avatar
Calnago
Posts: 5307
Joined: Sun Nov 07, 2010 9:14 pm

by Calnago

Yes, I realize that... that's why the actual build itself is so important, as you more than most everyone else knows. It took a couple early builds and less than even tension on the non drive side for me to realize the importance of that. Sure enough, a spoke went slack. But with wheels like that and with that many spokes it's pretty easy to do a quick true and get back home. Still, I tore it apart and rebuilt that wheel to much higher standards afterwards and never had a problem since. Learn by doing, and redoing when things go awry because you didn't think it mattered so much. Appreciate your thoughts. Thanks.

bm0p700f
in the industry
Posts: 3389
Joined: Sat May 12, 2012 7:25 pm
Location: Glermsford, Suffolk U.K
Contact:

by bm0p700f

I have the hed rims laced to record hubs and they are lovely. I also have nemesis rims on dura ace hubs and they are lovely too but feel slower, less snappy or whatever it is. Both can be riden quickly though.

Latterally Stiffer wheels do feel like they respond better. To make a material difference to cornering though requires you to come from reall flexinle wheels like the mavic gel280. Got those too and the have flex in the bends at speed.

Kinlin make the tb20. Very similar to the hed rim but a whole lot cheape. Go for this for light, stiff alloy tubular wheels.

I also have a set of carbon ti hubs with 80mm front flange seperation for a very stiff wheel and the old rear hub has a 61mm rear flange seperation. Tension balance is poor but spokes do not slaken off because the wheels are stiff. I also have a set of miche supertype hubs and the nds flange is even further out on these hubs. Nds spoke tension is low but again with 24 rear spoke count and cx ray spokes i have a very stiff rear wheel where spokes do not slacken of. I am no light weight either.

I have a set of velocity escapes in 32h drilling as this is all velocity had when i ordered to go with campagnolo chorus hubs. I have not had chance to build them yet.

I used to subsribe to the thinner spoke on the left side argument but have come to the conclusion the logic is flawed. My reasoning is it is lateral, radial of the wheel and the load applied that means a spoke can go slack. Obviously the spoke tension is important to. If the length change is big enough from the load applied the spoke will loose tension but thicker spokes on the nds mean you have a stiffer wheel so it takes a higher load for this to happen.

This is why stiff wheels lead to longer spoke life.

So for whatever wheel you pick build it as stiff as is practicle and that comes from the combination of the components used.

Kinlin tb20 with cx rays, D-lights or race (thicker means stiffer) on bitex, novatec, dura ace, record or various other hubs will make a lovely wheelset woth the best balance of characteristics.

by Weenie


User avatar
Calnago
Posts: 5307
Joined: Sun Nov 07, 2010 9:14 pm

by Calnago

All good info @bm0p700f: I've had the HED Belgium C2's laced with DT Aerolite spokes to a DT Swiss hub up front and a Powertap SLC+ in the back. Lovely rims for sure, one of the nicest alloy rims available I think. But the spokes would break at the flange of the Powertap hub. But the rims themselves I thought were great. They were clinchers.

Then I adopted the Ambrosio Nemesis for my durable alloy low profile tubular. I like them as much for their looks and history as anything, but they've proven to be absolutely stellar performers. Braking is also top notch as the brake track is not machined which has to help in that regard. But such a nice classic looking, super strong build. Love these wheels. Winter or summer, foul weather or perfect, always a treat to roll on. Not the fastest wheels, but hey, where have I got to be in such a hurry. I still have some unbuilt Nemesis rims and Record Hubs stashed away for future.

And I too, after trying the thinner spokes on the non drive side, have come to the hypothesis that the regular DT Comps on both will yield a more laterally stiff wheel. I have a good test mule to try it out on now, since the setup I have will ever so slightly graze the rear derailleur on steep out of the saddle hard effort climbs by a 200 pounder. I will rebuild these rims using DT Comps all round, then see if that grazing is eliminated or not. I think the key is getting NDS spoke tension as even as possible to prevent any of them from going slack.
Last edited by Calnago on Fri Mar 17, 2017 1:38 am, edited 1 time in total.

User avatar
ergott
Posts: 2721
Joined: Tue Apr 18, 2006 3:03 am
Location: Islip, NY
Contact:

by ergott

Comps on both sides will be indeed stiffer. That's not the point.

The logic isn't flawed. You can prioritize different aspects when choosing components, but there are always compromises.

bm0p700f
in the industry
Posts: 3389
Joined: Sat May 12, 2012 7:25 pm
Location: Glermsford, Suffolk U.K
Contact:

by bm0p700f

The thing is the stiffer the wheel the less of a length change you get in the spokes under a specific load so so long as the tension on the spokes is sufficent they wont go slack.

The only thing the thinner spoke on the NDS does is save a bit of weight.

I am just not sure what in different spokes on eoiher side actually achieves I dont think it can achieve what it sets out to do. The one thing we will agree on ergott is every component decision creates a compromise.

Yes the key is getting NDS spoke tension very even. Build with miche supertype hubs and it is essential. The NDS flange is at 46mm from centre and it is a 1:1 hub. This is not a hub I use in build for other people. the result though is a very stiff wheel.

User avatar
ergott
Posts: 2721
Joined: Tue Apr 18, 2006 3:03 am
Location: Islip, NY
Contact:

by ergott

You should really study what you are talking about more before you continue to post about this.

It's been explained numerous times.

racingcondor
Posts: 194
Joined: Fri Aug 27, 2010 4:22 pm

by racingcondor

From personal experience I love the way shallow profile box section rims ride. Great 'feel' and the flexibility makes for a nice smooth ride on the increasingly 'interesting' road surfaces of the UK (at the moment I'm either riding Mavic OP tubs or Easton EC90 55's and the Mavics are a much smoother ride even thought they have a heavier tyre, both on 25mm tubs).

If I was descending mountains I'd take a more modern deeper, stiffer rim. Too much flex can result in poor tracking through corners. Depends on priorities and how well it's built though.

bm0p700f
in the industry
Posts: 3389
Joined: Sat May 12, 2012 7:25 pm
Location: Glermsford, Suffolk U.K
Contact:

by bm0p700f

I have ergott. I understand your explanation I just dont think it stacks up with what I understand about the physics of structures. I though the point of forums was to discuss thing not to shut debate down.

Perhaps if you think I am wrong you can explain here why and I can reply. We can be polite about this as well.

For example the foundation stiffness (spokes) of the elastic beam (the rim) is related to a number of terms but directly proportional to the number of spokes, the elastic modulus of the spokes and the diameter of the spokes squared.

Going from 1.5mm spoke to a 1.8mm means a 44% in cross sectional area and the term for spoke stiffness is just over doubled for the NDS. That is not in significant and will have a big impact on how much length change you get for a given load.

In this paper and it is the only one to go on so it is not proof reducing spoke diameter from 2.0mm to 1.6mm has a huge impact on radial stiffness with a change of from 3500N/mm to 2500 N/mm.

So I have read and thought about this please dont think I have not.

User avatar
ergott
Posts: 2721
Joined: Tue Apr 18, 2006 3:03 am
Location: Islip, NY
Contact:

by ergott

Stiffness is not the only aspect of a wheel. For a rear wheel there is little lateral support on the right side due to the narrow flange spacing (cassett in the way). Since that side is more likely for deform from center, some builds are better off with thinner spokes. The reason is that for a given tension, a lighter gauge will have more elongation. Therefore that spoke allows for more rim flex before the spoke goes slack. This is more likely with a box rim that doesn't spread localized loads over as many spokes.

I'm on a phone so forgive the brevity.

Bombproof, your writing style invites the tone of my response because you dismiss a very well established building method as flawed with no immediate explanation. It's too narrow minded to only consider one aspect of a structure like a wheel when as you agree there are compromises made depending on the needs of the rider.

Sent from my SM-G920V using Tapatalk

Post Reply
  • Similar Topics
    Replies
    Views
    Last post