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PostPosted: Sun Aug 24, 2014 8:47 pm 
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Joined: Tue Jan 17, 2012 4:01 pm
Posts: 119
Location: Downtown Los Angeles, CA
So, I recently picked up a pair of Reynolds Thirty Two's 20/24 Tubulars, and there seems to be more deflection than I'd like when out of the saddle. I'm not talking about brake rub, but the feel of the wheel affecting the direction of the bike's travel. My Reynolds 46's are very stiff in this regard, and I tried my friend's Mavic CCU today, which was instantly, "ahh...that's better." The Reynolds are only a touch better than the Enve 25's that I had. Grinding up a steep climb, the Enve's would actually deflect so much they'd cause the bike to want to go in different directions.

So, I don't know if this is a radial or lateral stiffness issue (or both) or even simply a spoke tension issue. If it's not a spoke tension issue, could I get the Thirty Two's rebuilt with different hubs that would give me the same stiffness as the DV46's? Would Tune Mig/Mag hubs build into a stiffer wheel than the DT's that are currently on it? Also, as a note, the front wheel is j bend, with the spokes inward.

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Posted: Sun Aug 24, 2014 8:47 pm 


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PostPosted: Sun Aug 24, 2014 11:38 pm 
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Joined: Tue Nov 11, 2003 9:47 pm
Posts: 1697
Location: Santa Cruz, California, USA
Wheel lateral stiffness is determined mostly by rim stiffness, hub flange spacing, number and thickness of spokes, and to a lesser amount, spoke lacing pattern.

If the spokes are loose enough that they are completely detensioning as the wheel turns, that will reduce lateral stiffness. It's unlikely to be the problem- I have ridden a wheel with many nipples unscrewed to where they are completely slack and not noticed a lack of lateral stiffness (it was not a wheel I built).

The rear wheel is less stiff than the front due to dish for the cassette. And it gets more force when you are out of the saddle. So it is probably the problem here. You can't increase the number of spokes or change the rim stiffness if you want to keep the same rims. All you can do is change flange spacing by lacing to new hubs, or change lacing pattern, or both.

DT rear hubs have narrow flange spacing. You could increase stiffness by going to a hub with wider flanges. White Ind, Shimano have good spacing. Check out the Fairwheel Bikes hub review for info about the hubs you mention. BHS SL211 has decently wide flanges and costs and weighs less than those options.

You could increase the stiffness of the front by relacing with the spokes heads in. BHS sells a light front hub with very wide flanges. If the rear is laced radial on the NDS you could relace it 2x which will increase the bracing angle for 1/2 of the NDS spokes.


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PostPosted: Mon Aug 25, 2014 12:18 am 
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Joined: Tue Jan 17, 2012 4:01 pm
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Location: Downtown Los Angeles, CA
Thanks Eric.

I guess the question now is: If I rebuild the Reynolds 32's with wider flanges, is it going to be noticeably stiffer than the DT's? I'm 67kg.

Also, regarding rear vs front, while the rear may be deflecting more, I don't think I notice it as much. I swapped a Mavic CCU front wheel today (only front) and the handling while out of the saddle improved noticeably. Although, I need to put the DV46's back on because I have a suspicion that the 32's have introduced, for a lack of a better word, a feeling of bike flex when spinning at high speed (e.g. I noticed this while doing 40mph seated yesterday during the Montrose HS sprint).

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PostPosted: Mon Aug 25, 2014 3:02 pm 
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Joined: Tue Nov 11, 2003 9:47 pm
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Location: Santa Cruz, California, USA
It could be that different riding styles make a difference here- I've built some flexy front wheels and while I can notice the flex it's never been a problem. Then again I'm a climber not a sprinter.

I was going to suggest swapping one wheel at a time, that's a useful test.

You could stiffen the front for free (costing only your time) by disassembling the wheel and rebuilding it laced heads in. The required spoke length is the same but with the spoke on the outside of the flange the bracing angle is larger. You can use spokecalc to see what the difference in bracing angle would be. Rebuilding with a different hub like the BHS wide front would cost the hub, new spokes and your time but would get you a stiffer wheel (I've not looked up the DT flange dimension but the BHS wide hub is wider than normal).

If you're comfortable truing wheels and can be patient for an hour, a radial laced front wheel is pretty easy to build. If you're rebuilding with old spokes there's no need to keep track of which spokes went where as the stress is the same on all of them.


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PostPosted: Mon Aug 25, 2014 4:55 pm 
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Location: Islip, NY
Cheapest route that might be enough is to take the existing hubs and switch to DT Aero Comp spokes all around. For the rear, lace both sides 2X instead of radial.

That will improve things.

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Posted: Mon Aug 25, 2014 4:55 pm 


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PostPosted: Tue Aug 26, 2014 12:53 am 
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Posts: 119
Location: Downtown Los Angeles, CA
I'm not too concerned with the cheapest option as long as it's likely to result in addressing the issue. Heavier spokes would possibly fix the issue, but defeat the reason of buying the 32's.

If I want a 10xx gram wheelset that is stiff, it seems the best options are either:

1.) Enve 45 or Reynolds 46 rims, Sapim lasers (maybe can get away with supers?), and Tune hubs.
2.) Lightweights

I prefer to pick up things used, so LW's would run $2Kish. Enve/Reynolds rims are hard to come by but I could probably pick up a pair of factory Reynold's 46's with low miles for under a grand and maybe with a little patience/luck, can get some Tune hubs for under $400.

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