# Cracked Kinlin XR31T OC rims



## cooskull (Nov 30, 2013)

From what I can gleam searching the interwebs the Kinlin XR31T is about as bombproof of a rim as one can get and yet I have managed to crack a 32 spoke OC version of one in about 7K miles of riding. That rim replaced a Pacenti SL23 V2 which also cracked after ~15K miles, which in turn replaced a Velocity A23 rim that cracked after 10K miles. On the other hand my White Industries T11 hubs have outlasted these 3 rims and ~38K miles with just a preventive bearing replacement.

My rear wheel setup for all 3 rims is/was: 32 spokes, DS spokes being DT Swiss Competitions and NDS spokes are DT Swiss Revolutions; White Industries T11 V1 hub; various tubeless tires running at around 85-90PSI; Moderately strong ~210 lb rider with rides including some steep climbing and washboard dirt roads thrown in.

The Velocity A23 was built by a friend-of-a friend low volume wheel builder; the Pacenti SL23 by Exel Sports, and the Kinlin XR31T by myself.

So my question is are all these rims cracking just flukes (although the SL23s were notorious for cracks) or is my Clyde build along with running tubeless tires just hard on rims in general? I ask because I'm tired of replacing rims every 5-10K miles.


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## frdfandc (Nov 27, 2007)

Where are they cracking? Around the nipple hole? If so that is usually a tell tale sign that there is too much spoke tension.


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## cooskull (Nov 30, 2013)

Yes, the cracks were on either side of spoke holes along the apex of the rim. All three rims had the same rim cracking pattern, though the A23 and SL23 had cracks around most holes whereas the XR31T has only a few holes with cracks. For the XR31T I ended with a DS tension of 110kgf which is somewhat below the recommended 120kgf max threshold.


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## duriel (Oct 10, 2013)

Maybe tension unit calibration is something you should research.


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## carlosflanders (Nov 23, 2008)

32 spoke is not a clyde build. It's a perfectly normal everyday wheelbuild for a normal rider *5'10", 160 lb). Using DT revs turns it into a less than sturdy build. I'd advise 36 holes, DT Champs and spoke washers for a 210 lb rim destroyer.


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## Enoch562 (May 13, 2010)

Thats the first XR31 I've heard of cracking. I got quite a few of those out there and have had no issues. I've used it on builds for 235 lb riders. Maybe it time for a Chukker Rim?


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## frdfandc (Nov 27, 2007)

32 hole should be plenty strong. I'd skip the Revo's and just use the Comp's all the way around. I'm 220 and run 32 spoke builds on my road and MTB. Actually I'm running Stan's Crest's with DT Super Comps for the past 4 years. Only had to true the front wheel once.


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## changingleaf (Aug 20, 2009)

Climbing puts the most stress on the spoke holes because of the continuous hi torque translated to the rear hub. Try a stronger rim.


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## Lombard (May 8, 2014)

frdfandc said:


> 32 hole should be plenty strong. I'd skip the Revo's and just use the Comp's all the way around. I'm 220 and run 32 spoke builds on my road and MTB.





changingleaf said:


> Climbing puts the most stress on the spoke holes because of the continuous hi torque translated to the rear hub. Try a stronger rim.


This.

If I were you, I would go with a HED Belgium, H+ Son Archetype or DT R460 which are all stronger than the rims you have used and no heavier.

Also, don't overthink the off-center rim and different spokes on each side thing. There are plenty of clydes who ride conventionally built 32 spoke wheels with success. An OC rim is a weaker structure right off the bat. As I have said before, this is a solution to a problem that isn't very serious.

I would go with one of the rims I mentioned above and use DT Swiss Competitions on both sides. And use brass nipples, not alloy.

Also, are you sure your tensionometer is calibrated correctly? I'm not convinced your problem is a case of overtensioning as they were all built by different builders. Just saying. A good quality rim should be able to take 120-130kgF on the drive side. 110kgF is definitely not overtensioning.

But.....there is nothing wrong with going to a 36 spoke build on the rear. I believe all the rims I mentioned above have a 36 hole option. The weight penalty is minimal.


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## duriel (Oct 10, 2013)

Lombard said:


> I'm not convinced your problem is a case of overtensioning as they were all built by different builders.


I missed that.... dah!


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## cooskull (Nov 30, 2013)

Thanks for the replies.

As far as tension goes, I used a brand new Park TM-1 tool for the build. I suppose the tension could have been out of cal coming from the factory but it seems unlikely that it would be too far off. I was also uber careful with he build- I have not needed to adjust the tension at all on the front or rear as they have stayed dead-nuts true (obviously the rear is going out of true now that it's cracked but it's a lost cause at this point).

One thing I didn't do was debur/chamfer the spoke holes on the rim. Maybe there was a bur on the spoke holes which caused a stress riser on the rim. Seem possible given that only two holes are cracked.

I do believe riding tubeless puts more stress on the rims as well- more so than my Clyde weight. This is manifested by the rim losing 10-20kgf of tension when the tires are inflated. I know many posters here have built hundreds or even thousands of wheels, and probably many with this very rim, but how many of those wheelsets are heavily ridden by Clydes on tubeless setups? Maybe this combo is the "perfect storm" of factors that most rim makers wouldn't care to design for.

Anyways I tried this rim because it was by all reports bombproof. It seems I need to live with periodically replacing rims or go with something even heavier like the Chukker. Rims with 36 holes aren't really an option with my current setup as I'd like to reuse my hub. I will also try switching to all DT Comps in any case.


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## cdhbrad (Feb 18, 2003)

I have one set of wheels I built with the same rim and its been fine during the 2 years I've ridden it. However, I am a little lighter than you, about 20lbs., and I live in FL where there is NO climbing of any significance. Mine are on Dura Ace hubs, CXRays, 28 hole rear, and brass nipples and mine is not the OC version, so too many variables to draw any comparison. 
I do debur all my rims and, for these, I may have used nipple washers too, I can't remember. If you don't use washers, you might try that too......it can't hurt.


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## cooskull (Nov 30, 2013)

I've read mixed reviews on nipple washers. People usually say they can't hurt- but they also can't really say that they help either. My Pacenti build had nipple washers and it suffered the same fate. Specifically for the case of the XR31T, some reputable sources say that nipple washers don't really fit the tight rim cavity contours very well, and as such they are at best ineffective and perhaps even detrimental.


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## cdhbrad (Feb 18, 2003)

Suit yourself, hope you get the issue sorted out.


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## Enoch562 (May 13, 2010)

Lombard said:


> This.
> 
> If I were you, I would go with a HED Belgium, H+ Son Archetype or DT R460 which are all stronger than the rims you have used and no heavier.


Please tell me how you can verify this statement. How many of the XR 31, A23, or Pacenti rims have you built with? What has been your results?


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## Lombard (May 8, 2014)

cooskull said:


> Thanks for the replies.
> 
> As far as tension goes, I used a brand new Park TM-1 tool for the build. I suppose the tension could have been out of cal coming from the factory but it seems unlikely that it would be too far off. I was also uber careful with he build- I have not needed to adjust the tension at all on the front or rear as they have stayed dead-nuts true (obviously the rear is going out of true now that it's cracked but it's a lost cause at this point).
> 
> ...


Park tensiometers can be off right out of the box. These are not precision devices. For absolute tension, it is best to compare with another wheel that you know is tensioned correctly. These devices are best for relative tension comparisons.

I'm not sure running tubelss would put more stress on a rimn but not sure about this. Any tire (tubed or tubeless) will act as a boa constrictor against your rim and reduce the tensions slightly. 10-20kgF spunds about right.

Not sure I would try the Chukker, or any other Velocity rim. A couple wheel builders on these forums have had QC issues with Velicity - especially the A23. If you are looking to stick with tubeless, I don't think you would go wrong with the DT R460.


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## RoadCube (Nov 22, 2006)

No problem here as a bigger dude with Velocity rims. The A23 is not one of their stronger rims. Just looking at the profile, there is not much of a more stout “aero” look to it.
I was advised to go Fusion or Deep V in 32 hole or 36 hole A23. I went with a problem-free Fusion in 32.
I would ask the manufacturers what rim would work.
RC


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## Peter P. (Dec 30, 2006)

OP; you're a big guy probably applying a lot of torque on the wheel. Witness, you're not having a problem on the front wheel.

32H is probably fine. Contrary to Lombard, I'm a big fan of O/C rims as they spread the load better, and stay true longer, at least for me and the people I've built them for.

I think you need a more stout rim, just on the rear. The spokes you're using aren't an issue, and I do agree with Lombard that your tension level is within spec. As has been pointed out, the wheels have been built by different people yet they still continue to fail so it's not the builder that's the problem.


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## Clipped_in (May 5, 2011)

Enoch562 said:


> Please tell me how you can verify this statement. How many of the XR 31, A23, or Pacenti rims have you built with? What has been your results?


I'm not Lombard, and this is purely anectdotal, but I have seen very similar builds with Velocity A23, Pacenti SL23's and DT R460's develop nipple hole cracks under similar riding conditions with similar riders. Comparatively speaking, I have never seen a problem with HED C2's and Belgium+ under like circumstances. They are stronger rims.


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## cooskull (Nov 30, 2013)

I'll probably get some nice HED Belgiums, A-Force Al33s or even Boyd Altamonts for my new N+1 bike in a year or two, but for now I plan to fix the setup I have with minimal coinage to get by until then.

WRT OC or not- my current T11 V1 rear hub, while being absolutely nuke proof, has a very marginal DS/NDS tension ratio (maybe 120/50kgf) without OC rims. Thus the original reason to use thinner spokes for the NDS.

My lesson learned: Chamfer the spoke holes and find something with a good warranty (just in case). :thumbsup:


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## Lombard (May 8, 2014)

cooskull said:


> WRT OC or not- my current T11 V1 rear hub, while being absolutely nuke proof, has a very marginal DS/NDS tension ratio (maybe 120/50kgf) without OC rims.* Thus the original reason to use thinner spokes for the NDS.*


*Thinner spokes on the NDS WILL NOT change your tension disparities.* Only an OC rim or a hub with different flange sizes will do this.


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## cooskull (Nov 30, 2013)

Lombard said:


> *Thinner spokes on the NDS WILL NOT change your tension disparities.* Only an OC rim or a hub with different flange sizes will do this.


I think you're missing the point of why people do this. Sure, thinner spokes aren't going to change the DS/NDS tension ratio- that is determined by the hub and rim geometries. But thinner spokes do stretch more than thicker ones under tension- which in theory allows them to better handle (not go slack under) lower or near zero tensions better than thick spokes. When the NDS tension is in the 50kgf range or below, NDS spokes going completely slack under load is a concern.


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## cdhbrad (Feb 18, 2003)

I built a set of wheels for myself earlier this year using WI T11 hubs, CXrays, and Al33 rims. Rims were very easy to work with and I've been very pleased with ride. I don't ride them as tubeless, but they are "tubeless ready". 

Bike Hub Store has these rims with WI Hubs as a "kit" at a very good price. I've built 4-5 sets of the WI/ Kinlin 31W from the BHS Kits for friends and everything is included except Rim Strip. Spoke lengths, etc. have been perfect too. I imagine the AL33 kit is the same in terms of accuracy of spoke measurements, etc.


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## Lombard (May 8, 2014)

cooskull said:


> I think you're missing the point of why people do this. Sure, thinner spokes aren't going to change the DS/NDS tension ratio- that is determined by the hub and rim geometries. But thinner spokes do stretch more than thicker ones under tension- which in theory allows them to better handle (not go slack under) lower or near zero tensions better than thick spokes. When the NDS tension is in the 50kgf range or below, NDS spokes going completely slack under load is a concern.


Well in theory, a spoke with more butting will flex more in the middle and therefore be less stressful on the weakest parts of the spoke - the j-bend and the nipple end. However, in reality, a lightly butted spoke like the DT Revolution will give you plenty of flexing in the middle to prevent fatigue at the weak points. But a thinner spoke is no less likely to go slack. This is a myth. It is still subject to the same forces overall even if the forces are concentrated on different parts of the spoke.


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## 4slomo (Feb 11, 2008)

Was the wheel built with two-cross or three-cross spoke lacing? At your riding weight, 32 spoke wheels are appropriate, I generally increase to 36 spoke wheels at about 250 lb riding weight.

I've built and rebuilt a number of wheels with Velocity A-23 rims, both symmetrical and off-center, and deburr/burnish the spoke holes. The rebuilds had initially been built by others. My impression is that the alloy Velocity uses, coupled with the rim geometry, limits the durability of those rims at higher riding weights. I built my personal wheel set with CX-Ray spokes three-crossed and DT Swiss 240s hubs, and only needed to true them occasionally. My riding weight is 10-15 pounds less than yours, and I'm also fairly strong.

The Park tensiometer is not designed for high accuracy or precision. I replaced mine after two years, with a DT Swiss tensiometer.

You do need to be riding with a stronger rim. The HED Belgium+ is a very nice and strong rim, using an aluminum-scandium alloy. I don't like using it with the T-11 hub, due to the DS/NDS spoke tension variance. For example, DT Swiss also makes some strong rims (RR411 w/PHR washers, R460) where you can maximize DS spoke tension to correspondingly maximize NDS spoke tension.



cooskull said:


> From what I can gleam searching the interwebs the Kinlin XR31T is about as bombproof of a rim as one can get and yet I have managed to crack a 32 spoke OC version of one in about 7K miles of riding. That rim replaced a Pacenti SL23 V2 which also cracked after ~15K miles, which in turn replaced a Velocity A23 rim that cracked after 10K miles. On the other hand my White Industries T11 hubs have outlasted these 3 rims and ~38K miles with just a preventive bearing replacement.
> 
> My rear wheel setup for all 3 rims is/was: 32 spokes, DS spokes being DT Swiss Competitions and NDS spokes are DT Swiss Revolutions; White Industries T11 V1 hub; various tubeless tires running at around 85-90PSI; Moderately strong ~210 lb rider with rides including some steep climbing and washboard dirt roads thrown in.
> 
> ...


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## jnbrown (Dec 9, 2009)

I cracked one of those and also a Pacenti Sl23.
The Kinlin was on the rear of my tandem for a few years and I think it was just normal considering the beating it took, our combined weight is about 260 lbs.
The Pacenti was on the rear of my road bike and it was quite old and they are known for cracking. Replaced it with an Easton R90SL which I think will last longer.
I also used a Park tensiometer. I think some rims are just more prone to cracking and it isn't necessarily due to over tensioning.


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