Kinlin XR22 Build...24/28 ok for 175 lbs?

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turbomatic73
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Joined: Wed Jun 02, 2010 1:14 am

by turbomatic73

Contemplating a Kinlin XR22 build with 24 front (radial) 28 rear (2x) config. Given the rim's relatively shallow profile, I'm not sure the spoke count will be high enough. I weigh 175 lbs. Any thoughts? I like the idea of using a wide/shallow rim to get the ride as comfy as possible...aero is not a priority.

I have a wheelset now that's 24/28 and it's bombproof, but I'm using Kinlin XR300's, which are much taller and the ride is pretty harsh. FWIW I'll be using CX-rays for the new build.

alcatraz
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by alcatraz

Probably depends on what kind of spoke you'll be using. Stronger and you can make due with less, and vice versa.

I imagine you add the spoke tensions all up for the whole wheel. A heavier rider needs a higher total tension (within that spoke's reliable limits).

/a

by Weenie


bm0p700f
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by bm0p700f

yes it will be fine. Spoke tension should not vary with rider weight. Build to 1250N DS rear and use spoke nipple washers all round and it will be a fine wheelset. I do alot of these. never had a failure.

alcatraz
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by alcatraz

I think bm0p700f presumes the same or similar spoke is used for all the builds. Then the number of spokes is the way to make the wheel support more weight.

If you had a free choice of spoke it would be different. My mind goes to like corima/campagnolo wheels that make use with quite few spokes while maintaining a high rider weight limit. I've held a bora ultra 50 rear wheel with 21 spokes and the tension is quite insane.

Obviously when designing a wheel from scratch and having control over production of each part this is possible. Normal builds use parts where the manufacturers assume certain limits. Like how much maximum tension the hub and the rim can support for one single spoke, as well as the nipple. The greater the tension the higher quality construction/materials used = expensive/heavy.

/a

Multebear
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by Multebear

turbomatic73 wrote:
24 front (radial) 28 rear (2x) config.



I'm the same weight as you, and have a couple wheelsets with the same spokeconfig. Only difference is, I've done them 2x/3x. I find them very strong, stiff and stable. I would recommend that instead of radial/2x.

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F45
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by F45

I'm on some DA 9000/Aerolite/Xr22T 24/28 at 155lbs. They're plenty for me, and I hammer up 20% grades out of the saddle. Radial front /2x both sides rear.

There is zero benefit to crossing front spokes for this build. It will be less stiff and take a little more time to build. No point.

Less cross is always more stiff. 2x than 3x, etc...

bm0p700f
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by bm0p700f

Alcatraz. Actually with washers the kinlin rim will hold very high tensions. The limit is the nipples. They round or break when pushing the tension above 1300n sometimes. Thats why factory wheels have big nipples. Still the tension i use is more than enough and low spoke count count wheels are not inherantly better. Such wheels need clever design solutions like lage nipples, variable thickness rims, grouped spokes and other tricks. But you can build a set of wheels that is lighter and cheaper than the shamals with the kinlins and it will perform just as well.

alcatraz
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by alcatraz

Makes a lot of sense.. Thank you. So to simplify number of spokes is the safe way to go.

I'm only 60kg and the bike 6kg so with under 40kg load per wheel I can get away with quite few spokes (standard nipples). I did have trouble keeping my 20/24h kinlin xr200s with dt champions true at first but then I realized they weren't that well tensioned. After bringing it up they were solid for my weight. Also I don't like round spokes because they are harder to fine tune at high tension. Almost impossible for the rear DS.

/a

MarkMcM
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by MarkMcM

turbomatic73,

I think you might want to re-think your premise - a shallower section rim will not necessarily provide a more compliant ride. There are two reasons - the first is academic, and the second is practical:

1) Wheel vertical stiffness is governed more by the spokes than by the rim. A wheel with a deep, heavy rim and a small number of spokes will actually be more compliant than a wheel with a shallow rim and a large number of spokes. If you think about this, it makes sense -vertical compliance is when the hub gets closer to the ground, and since the spokes are in a direct line between the hub and the ground, the number and thickness of the spokes will determine how much force it takes for the hub to move a given distance relative to the ground (i.e., the vertical stiffness of the wheel). This principle is not just theory, it has been directly measured many times. Here's a good source about when Zipp was designing wheels for the Paris-Roubaix, and found out that carbon rim wheels were actually more compliant than the wheels with shallow aluminum box section rims that were previously favored:

https://silca.cc/blogs/journal/115178628-road-to-roubaix-the-complete-story

Here's another test showing measured wheel stiffnesses. Note that the stiffest wheel in the test had lightest, shallowest rim (GEL330) - but it also had the most and thickest spokes (36 2.0mm straight gauge):

https://www.sheldonbrown.com/rinard/wheel/grignon.htm


2) And now the practical (and real) answer: As you can see from the wheel stiffness tests above, all wheels have very, very high vertical stiffness. So high, that they provide no meaningful compliance/comfort. Here's an article which includes a discussion of riders doing blinded tests on wheels, and it was found that riders couldn't really feel any stiffness differences between them:

http://www.slowtwitch.com/Tech/Thoughts_on_science_perception_4571.html

Cervelo measured the compliance of the various components between the road and the rider, and found that wheels had the least compliance of all the components. While it should not be surprising that the tires had the most compliance, they found that even the handlebar tape had several times more affect on compliance than the front wheel. Or in other words, even choosing the most compliant wheels will have less affect on the ride than selection of handlebar tape or shorts.

http://weightweenies.starbike.com/forum/posting.php?f=113&mode=reply&t=147395



So therefore, you're selection of rims should be based on other factors (strength, durability, weight, aerodynamics, etc.), and not at all on ride compliance.

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F45
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by F45

A comment about nipples - I had a rear wheel with aluminum nipples. I bent a rim lip running too low pressure over some rocks so I decided very objectively and with a completely cool head to slam it repeatedly into the ground. The action snapped a few spokes, ripped some nipples out of the rim bed, and broke the rim in a few places. What surprised me was that the nipples were perfectly fine.

I put those nipples on the rear of a new mountain bike wheel build. We'll see how long they hold up.

by Weenie


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