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Discussion Starter · #1 ·
On this weekends ride, it was wet and we started up a bridge so as I pushed from a stop the bike was creaking as I pedaled up the bridge. At the first stop I began to go over the bike looking for the noise.

Found it, I was causing the rear wheel to touch the brake pad and with the wet conditions it was squeaking as it touched. I was able to push the top of the wheel from side to side with my hands and make it touch the brake pads.

Now I am a solid mid pack rider, 49, 210 lbs, more of an endurance specialist and not a strong powerful rider.

The Bike is a Fuji Altamira, Team frame set so that's supposed to be a very stiff frame.

Wheels are Shimano RS80 C50 wheels.

Is this flex normals? Wheels not very stiff? Something wrong?
 

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Forever a Student
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Normal. If you can't push your wheel back and forth touching the pads, something's wrong.

Make sure your skewer is a Shimano one and keep it nice and tight with the wheel perfectly centered.
 

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I have a lot of wheels and not one of them touches the brake pads.

Maybe the play comes from the hub.
Here you can find a short tutorial about how to adjust loose ball bearings.
 

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How close are you pads to the rim? All wheels flex when pushed in by hand or swaying the bike and what's normal or not depends on how much and how much force it takes.
 

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All wheels will flex to some degree, especially when you're pushing with a lot of force. Your pedaling exerts a torque on the rear wheel that points perpendicular to the lever arm (in this case the cog).

 

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A little flex is normal, but some wheels have more than others. Wider rims will feel stiffer, narrower will have a bit more flex. Also, your rear wheel has a spoke count of only 20. At 210 lbs., you may want something with a higher spoke count.

Some frames have more flex than others as well.
 

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Discussion Starter · #10 ·
I think that's what I will try, and see what my LBS thinks about a little tighter spoke tension
 

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I think that's what I will try, and see what my LBS thinks about a little tighter spoke tension
Hopefully he does not think much about it because adding tension will not increase the wheel stiffness.
 

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Hopefully he does not think much about it because adding tension will not increase the wheel stiffness.
This. Unless the spokes are REALLY LOSE to the point of being dangerous and unrideable.
 

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If the wheel is in good shape then I recommend increasing the brake clearance and making sure the brakes are centered around the rim.
...except perhaps for the centered part. I find I get more deflection at the caliper toward the NDS, perhaps due to the effect of chain tension deflecting the rear triangle. My old Ti bike exhibited this most.
 

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According to this article at Slowtwitch: Debunking Wheel Stiffness, a stiff deep section rim on a low spoke count wheel can deflect more at the point opposite the point of load (i.e. at the brake caliper) compared to a less stiff rim.
Definitely an interesting read. So according to this, if you want a stiffer wheel, the best way to achieve this is with a higher spoke count and thicker spokes.
 

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Also wider flange spacing and a stronger rim.
According to the article, he claims that spokes do more to stiffen a wheel than the rim does.
 

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According to the article, he claims that spokes do more to stiffen a wheel than the rim does.
Yes, but the rim helps. If you want to increase wheel stiffness, it's a combination of things you should do, not just one or two. Finding the good balance with all aspects to increase stiffness (in my opinion) is a good way to approach wheel building.
 

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Yes, but the rim helps. If you want to increase wheel stiffness, it's a combination of things you should do, not just one or two. Finding the good balance with all aspects to increase stiffness (in my opinion) is a good way to approach wheel building.
This makes sense. As the old saying goes about the chain being only as strong as the weakest link. This article may explain my perception of ride harshness on the wheels I recently built. I did a conventional 32 spoke (DT Competition 14/15/14) 3x build with HED C2s and 6800 Ultegra hubs. Compare that with my factory Shimano RS-21 wheels with bladed spokes 16 front/20 rear. My new wheels are definitely stiffer and more stable, but at the cost of a rougher ride - which for the most part, I've gotten used to.

For my next build, I'm contemplating going with 24 front 2x/32 rear 3x to soften the front a bit, with DT R440 rims and Dura-Ace 9000 hubs. This probably won't happen until fall when lack of evening daylight makes after work rides history. :)
 

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I'd bet that your perception of stiffness in the HED set you built is that the wider HED rim is your tire pressures need to be lowered to exactly correlate to the pressure on your Shimano wheels. The exact same tires moved from Shimano to HED would inflate a lot bigger, thus needing less volume to feel the same.

Tires have mm's of deflection available to influence ride. Wheels have at least an order of magnitude less deflection. Think about it this way - if you deflect your tire 25mm or so, you bottom the tire out and may well need a new inner tube. If you deflect your rim the same amount, you may well need a new rim.

Variances in lacing pattern have basically zero effect compared to what your tires have to offer.

Bump down the pressure in the HED wheels and I bet they start to feel a lot less harsh.
 
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