Which will be the stiffer wheel and is it worth it?

Discuss light weight issues concerning mountain bikes & parts.

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Nicholas68
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by Nicholas68

Before people say this doesn't matter or it wont make a difference this is the WW forums where we aim for the best performance/weight we can get out of our bike even if it's minuscule. So if there is any experienced wheel builders out there or people who know information about this topic then I'd greatly appreciate your opinion.

I'm trying to toss up between the extralite hyperfront or hyper J front hub. My main question refers to spoke tension. The hypercamber uses 70+/-10 on non disc and 110+/-10 on disc side as the spoke tension and the hyper J is 10 less on each side. With 29er's having the larger wheels I'd assume spoke tension would make a difference since these hubs have low tension due to being light weight and one side being radial laced. How big of a difference would this make with wheel stiffness?

Weight wise the hyper J is 9 grams heavier but uses around 4-5 grams less spoke. So weight isn't really changed. The hyper J uses J bend spokes and hyperfront uses straight pull so I'd assume this would make some difference to stiffness. The Hyperfront is around $80 dearer due to the cost of straight pull spokes.

With tension from my research I've heard the weakness is always the rims with spoke tension and the hubs will handle whatever the rim can, but I will be using carbon rims which can go to 180kgf so the hub will be the weak point in this build. Has anyone with these hubs gone above the recommended and gone say 90kgf on non disc and 130 on disc side?

Or honestly will this make no difference at all?

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WMW
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by WMW

Tension doesn't effect stiffness at all... so long as you don't get to the point where spokes go slack. Higher tension means the wheel will take a larger load before it gets to that point.

Bracing angle is the most important factor for stiffness... along with rim stiffness, with spoke stiffness farther down the list.

J or straight pull should make no difference if the wheel is built properly. I'd probably go with the J and cross lace both sides just to improve the longevity of that flange. You could bump up the tension a little but I wouldn't go past 130kg.

What spokes and rims?
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Nicholas68
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by Nicholas68

WMW wrote:Tension doesn't effect stiffness at all... so long as you don't get to the point where spokes go slack. Higher tension means the wheel will take a larger load before it gets to that point.

Bracing angle is the most important factor for stiffness... along with rim stiffness, with spoke stiffness farther down the list.

J or straight pull should make no difference if the wheel is built properly. I'd probably go with the J and cross lace both sides just to improve the longevity of that flange. You could bump up the tension a little but I wouldn't go past 130kg.

What spokes and rims?


Okay, that makes sense, I'm 65kg so hopefully I won't need super high spoke tensions so it doesn't become flexy under hard braking. The hub I'm looking at also says to radial spoke the J bend one on the non disc side. And tangential lace the disc side. So same lacing pattern as the straight pull. Would this lacing make a weak wheel compared to if I got a tune and did 3 cross on both sides? Weight difference is around 40 grams.

Rim's are the light-bicycle wide 29er rims, 24-25ID and 30mmOD then spokes will be Sapim cx-ray. I have red alloy nipples but not sure if I'll use them or brass since it's a carbon rim. So hard to give up the red colour and 45 grams at the outer point of the wheels.

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WMW
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by WMW

Definitely use aluminum nipples... no reason not too. I use tefgel antiseize and it works real well.

I figured tangential lacing would be easier on the flange, but if radial is what they recommend, that is probably fine. I wouldn't say it is necessarily weaker... you are just making the disc side take all the torque loads. More likely to be an issue if you were a heavy weight.
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Nicholas68
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by Nicholas68

What about corrosion with the nipples from the carbon rims and tubeless fluid. I've heard that it will only let the nipples last a year or so. I live around 40-50ks from the ocean. So don't think salty air will be an issue, just the carbon/fluid will corrode them. Least that's what I keep hearing.

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WMW
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by WMW

Never heard that before. Don't know why sealant would be getting in there anyway... it's supposed to be trapped in the other rim cavity.

Use tefgel on the nipple seats as well... and anodized nipples. If you want, use nipple washers... that would certainly eliminate any chance of galvanic corrosion.
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Nicholas68
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by Nicholas68

WMW wrote:Never heard that before. Don't know why sealant would be getting in there anyway... it's supposed to be trapped in the other rim cavity.

Use tefgel on the nipple seats as well... and anodized nipples. If you want, use nipple washers... that would certainly eliminate any chance of galvanic corrosion.


That was my thoughts. Might be talking about internal nipple carbon rims or something. When looking at a corrosion chard carbon has little effect on alloy, but google searches seem to say otherwise. Will definitely pick up some tefgel. It's basically the same as spoke prep I'm assuming? With probably a lower price tag since it seems to be available everywhere in my area. Suppose worse that will happen is the nipples will corrode and I'll have a couple wheels to rebuild.

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WMW
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by WMW

Tefgel is made to prevent corrosion between stainless steel and aluminum... on boats... in the ocean. It works... for many years.

Nipple washers might be a good idea anyway on those rims.
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dwaharvey
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by dwaharvey

Ron, what makes you say the LB rims would benefit from nipple washers?

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WMW
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by WMW

The grinding of the nipple on carbon tends to release little carbon particles that cause friction. The washer spreads the load out a bit also.
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