Advice to fix lateral rim movement

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Thanos
Posts: 30
Joined: Thu Feb 08, 2018 11:49 pm

by Thanos

I'm running an ENVE 45 classic rim (tubs) from 2011 with Extralite SLX hub and Sapim CX-Ray spokes (24) in the recommended lace pattern.

I've recently moved to an Émonda SLR frame with direct mount brakes and I'm getting brake rub in my rear wheel, particularly when climbing out of the saddle.

I'm pretty light at 140lbs and I don't think I put that much power out (for Thanos!)

So, what can I (or my LBS) do to fix this?

Re-tension the spokes?

New, better hub?

Etc.

The bike is just about perfect, if I could only fix this one issue.

One proviso, I want to keep it WW, hence the Extralite hub in the first place.

Thanks, Thanos.Image

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Last edited by Thanos on Fri Jun 15, 2018 12:25 am, edited 1 time in total.

by Weenie


shimmeD
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by shimmeD

You didn't say what bike the rear wheel was on previously. I don't know also if it would be fair to assume that you did not have brake rub on the previous bike.
Less is more.

alcatraz
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Joined: Mon Aug 29, 2016 11:19 am

by alcatraz

Check what kind of play you have. Maybe it's just a flexy wheel. Some brake calipers don't open as wide as others do when the brake lever is released. I have heard though that direct mount brakes are superior with this so I don't suspect this to be your problem. (I might be wrong though)

When setting the brake pad gap on your rear wheel you can't just set them apart the same distance as you would do on the front. Rear wheels are weaker to the DS side than they are to the NDS so you need to adjust the gap larger on the DS side. Check simply by holding the seatstay and putting one thumb on the rim and giving it a gentle press. See how far the wheel flexes and compare both sides. One side will flex more and that side needs the larger brake pad gap.

If your extralite microtuner has been set correctly and you still have some lateral play it's possible your bearings are not pressed in properly. What fixed the play in my old hub (not extralite, but also alloy shell+axle) is to put retaining compound on the outer AND inner race when mounting the bearings (especially the inner hub bearing. Apparently the place where the bearing rests on the axle had been ground away a bit. The compound did a great job of filling up that gap. It removed 80% of the lateral play in my rear wheel.

So what I'm saying is, use the microtuner but don't give up if it doesn't work. Just take it apart and inspect. Try locite 641 retaining compound or similar.

My wheel doesn't even have a microtuner and it's still really nice. I changed all the bearings though to SKF rubber seal bearings. Lowest play I've ever discovered in a bearing. Maybe not the fastest seals but feels very smooth and solid. Dirt cheap too. I add some light oil to make them spin almost like ceramic bearings, possibly even better.

NickJHP
Posts: 75
Joined: Wed Feb 14, 2018 2:22 am

by NickJHP

Somewhat counter-intuitively, the stiffer the rim the more likely you are to get brake rub, particularly with low spoke count wheels. This is because as the sideways load between wheel and road causes the rim to get deflected sideways at the bottom, the stiffness of the rims means that there will be more of an opposite deflection at the top of the wheel nears the brakes. See here:

https://www.slowtwitch.com/Tech/Debunki ... _3449.html

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Calnago
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by Calnago

Yes, I’m well aware of that “study”. But I’ve always wanted someone to explain this then...
Lightweight (the brand) wheels are certainly known for their stiffness. No argument from me on that front. Are they laterally stiffer than Boras for example?... I think so. Yet, I once did one of my “practical” real world experiments which tested just how close I could have the brake pads with no rubbing for both wheels. The Boras needed the brake pads to be significantly further from the rim for no rub to occur under load than the Lightweights did. That does not really jive with the theory presented in that article. How come?

Heres the deal, there’s often more going on that just the flex or stiffness of the wheel. Not saying that’s the case here, but the SLR is certainly on the lighter side of frames. Wonder if maybe the stays are flexing along with everything else enough to be contributing to the brake run.

Colnago C64 - The Naked Build; Colnago C60 - PR99; Trek Koppenberg - Where Emonda and Domane Meet;
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Thanos
Posts: 30
Joined: Thu Feb 08, 2018 11:49 pm

by Thanos

Sorry, my previous frame was a 2010 Madone (Project One OCLV Red), so virtually the same frame as the Émonda. Campagnolo Record caliper brakes, set wide enough to not have brake rub.

I don't think it's the frame @colnago, it's super stiff, I just think because the brakes are direct mount EE brakes, there is less of a gap than on my Madone. So, I've always had lateral play, but was able to work around it on my previous frame.

So, now rather than try and work around it, I want to see if I can actually fix, or reduce as much as possible the core issue of play.

My wife has the same rim but with a Chris King R45 hub and has no lateral play. So, I suspect the Extralite hub, it's always been flexy, so I guess I really want to know if everyone's Extralite builds are like that, or is mine a bit of an exception and there is an issue with the wheel build, micro-tuner, bearings etc?

Which is what @alcatraz is saying, thanks for that info. I don't service my hubs myself, I'll pass the info. along to my LBS who do.

I'm quite happy to buy a new hub and have the wheel rebuilt, but I'd like to explore cheaper options first, before I get into the question of which WW hub to replace it with.....

Thanos

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Last edited by Thanos on Fri Jun 15, 2018 6:46 am, edited 1 time in total.

NickJHP
Posts: 75
Joined: Wed Feb 14, 2018 2:22 am

by NickJHP

The spoke "stiffness" (ie amount of elongation with increase in stress) also plays a part, so I would say that the skinny stainless spokes in the Bora wheel elongate more than the C-F spokes in the Lightweight wheel, and therefore the rim will deflect more opposite the point of contact with the road.

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Calnago
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by Calnago

Ok... I’ll accept that I guess. Probably explains why the Boras feel less harsh as well I suppose.
Colnago C64 - The Naked Build; Colnago C60 - PR99; Trek Koppenberg - Where Emonda and Domane Meet;
Unlinked Builds (searchable): Colnago C59 - 5 Years Later; Trek Emonda SL Campagnolo SR; Special Colnago EPQ

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kgt
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Location: Athens, Greece

by kgt

NickJHP is correct
LW is stiffer in every direction (and feels different) than any other wheelset because both carbon rim and carbon spokes contribute to its stiffness. A carbon rim on 'classic' steel spokes cannot match this stiffness (and feeling).

3Pio
Posts: 866
Joined: Wed Mar 09, 2016 7:13 pm

by 3Pio

I have the similar problem with Campagnolo Bora 50 AC3 wheelset on my Colnago C60 (and first time ever on any bike to have brake rub...)

On same frameset, with my Bora 35 3D Diamond or Shamal Ultra, no brake rub at all... On Bora 50 i can feel when i start sprinting... When i press rims on Bora 50 i can feel them how soft they are (and i have a feeling that if i press them any stronger, i can crack them..) , and on Bora 35 much stiffer (when i press the rims feel solid, not squishy as Bora 50)

Also wondering for solution for this problem (i thought maybe to put more tension on spokes...)

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LouisN
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Location: Canada

by LouisN

There is nothing you can do to "cancel" lateral rim movement. It's just natural.
For brake rub, easy fix. Brake pads further away. Done.
IMO the cause also has to do with pedal stroke/style. If you are a "grinder", have an uneven pedal stroke and throw everything on the downstroke, on one side, the brake rub is worse. I know many light racers that have a grinding style and they all place their brake pads further away from the rims to avoid brake rub.

Louis :)

BdaGhisallo
Posts: 1926
Joined: Wed Mar 17, 2004 1:38 pm

by BdaGhisallo

If you want to minimize brake pad rub with your current hubs and rims, get them re-laced with Sapim Race spokes or some other similar but thicker spoke. Lateral rigidity is boosted by wider hub flange spacing, greater numbers of spokes, or more material holding the hub and the rim together. Since your hub and rim are fixed, the only option is to go for thicker spokes.

I have had a number of Enve wheels over the years - 3.4, 4.5 and 6.7 wheels. The 3.4 wheels I had where always flexy when built with the standard CX-Ray spokes, as they come pre-built from Enve. I even tried a custom build with aero spokes thicker than CX-Ray spokes, using the CX-Sport. I still had noticeable brake rub. When I got a 3.4 rear laced with Sapim Race (round DB spokes, but more material than the CX spokes) the brake rub was very much diminished.

Hexsense
Posts: 461
Joined: Wed Dec 30, 2015 12:41 am

by Hexsense

Sapim CX-Sprint is both stiffer and cheaper than CX-Ray.
That sound like a great spoke to use for stiff aero wheels.

BdaGhisallo
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Joined: Wed Mar 17, 2004 1:38 pm

by BdaGhisallo

Hexsense wrote:
Mon Jun 18, 2018 7:37 pm
Sapim CX-Sprint is both stiffer and cheaper than CX-Ray.
That sound like a great spoke to use for stiff aero wheels.
I wouldn't bother with them. I tried them in a White Ind T11 / Enve 3.4 wheel and they made no appreciable difference in lateral stiffness compared to CX-Ray. Sapim Race spokes cured the issue for me.

by Weenie


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ergott
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by ergott

Race is 1.8mm round along the butted length. The Sprint is forged from 1.7mm round spoke so less stiff than Race, but more than CX-Ray. Heck if you have a competant builder you can use straight gauge spokes and really make a difference. The alloy of SS used in modern spokes is much better than of old when straight gauge really had to be avoided.

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