Technical > Wheels, Tyres and Brakes

Andra rim cracks

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hendrich:
Steve,
We used ZAC19 prior to the Andra based on a (reputable?) bike shop recommendation. We cracked those rims in less than 1000 miles. After that and other spoke breakage problems, I gave up on bike shops in the states. With the exception of perhaps of a shop or two in the whole of US, there is still too little knowledge of proper wheel building for Rohloff hubs.

Ryde literature says I should use "DFL" washers, but nowhere can I find specifications or even where to buy such washers. I will wait for Ryde. After that, my next attempt will be with 4mm SS washers, 4.3mm ID, 7.5mm OD, 0.3 or 0.8 mm thick, which I can buy. Those washers will fit past the outer wall holes and in particular the 0.3 mm are thin and will conform to the curvature of the rim surface. I hope a little extra pressure distribution will be the fix.

mickeg:
If your Rohloff lacks the flange rings, you might want to add them when you rebuild your wheel.  They recommend that you add them if a wheel is rebuilt, but I went ahead and added them simply because in some of my travels I am very far from help, I was not rebuilding my wheel.


--- Quote from: hendrich on November 01, 2021, 05:51:41 PM ---... With the exception of perhaps of a shop or two in the whole of US, there is still too little knowledge of proper wheel building for Rohloff hubs.
...

--- End quote ---

I am in Madison, WI.

I had my Nomad Mk II in a bike shop a few years ago, it was a high crime area so I brought my bike inside.  I was not there for service, looking for parts or something like that.  A mechanic was looking at it, he knew that I had built up the bike.  He mentioned that he was going to build up a Rohloff wheel for a customer and he was curious why I did not do it three cross.  I asked him if he had read the Rohloff instructions to wheel builders.  He said he had built wheels before.

A neighbor is a bike mechanic, he has told me that my Rohloff is the only one he has ever seen.  And he works at a fairly large shop near campus, they see a lot of bikes coming through that shop.

I was talking to someone I met on a bike trail we were both biking along, he said he was going to the shop to see how his tandem that he ordered was coming along.  Since I was going past the shop, I said I would stop in to, as I was curious since mine was the only Rohloff I had seen in my county.  The shop had the shifter cables reversed, first gear said 14 on the shifter knob.

In other words, I am glad I built up my own Rohloff wheel after reading the instructions to wheel builders.  I do not have a spoke tension meter, but a friend of mine volunteers time at a bike charity as a mechanic, he has access to a gauge and checked the tension for me.

There is a guy in Madison that has worked on the innards of a Rohloff hub, but I think he has not opened up a hub in years.

hendrich:
Thanks, my hub has the rings.


--- Quote from: mickeg on November 01, 2021, 08:48:23 PM ---He mentioned that he was going to build up a Rohloff wheel for a customer and he was curious why I did not do it three cross.  I asked him if he had read the Rohloff instructions to wheel builders.  He said he had built wheels before.
--- End quote ---

I am sorry to say that is what I have observed also. Wheelbuilders in the US with otherwise much experience have done little or nothing to learn the nuances of Rohloff wheel building.

hendrich:
An update to my post. I contacted ryde about the problem, even tried in Dutch (see below), but ryde never responded. I added 0.3 mm thick washers and tensioned to 110 kgf (w/tire). I removed a spoke from a hole with a crack and examined the profile of the hole carefully. I found no evidence that the hole was in anyway damaged, which supports my suspicion that the cracks are cosmetic in the anodizing. After another 1000 miles, the cracks have not changed and the wheel remains true (<10 mils) at tension, but more mileage is needed for a conclusion.

I also contacted the place I bought the rims from, bikehubstore in North Carolina. The owner was helpful/knowledgeable and said he has sold many ryde rims and never heard of crack issues. He sent me a new rim at half price with free shipping. I recommend that store if you are in US. BTW, I have been using a Unior nipple wrench for all this work, like it.

Mike

Hallo,
Ik bouwde de wielen voor onze tandem, gebruik makende van Ryde Andra 35 (559) velgen, 36 Saprim spaken en Saprim polyax nippels. Ik kocht de velgen verleden jaar.  Helaas, na zo'n 10000km hebben zich 5 mm lange haar scheurtjes gevormd in vier van de spaakgaten in de velg van het achterwiel die te zien zijn op de bijgaande foto. De betreffende spaken zijn niet naast elkaar maar bevinden zich in geheel verschillende delen. Het wiel blijft goed uitgelijnd onder een gemiddelde druk van 105kgf (beide kanten, Rohloff hub) met een uitwijking van 15%. Het wiel ondervond geen dramatische schokken gedurende deze periode.

Uit uw handleiding ontneem ik dat iedere velg een gewicht kan dragen van 130kg en een druk van 140kgf. Ons totale gewicht, inclusief de fiets en alle bagage is 210kg en de spanning in de spaken is 105kgf. Beide waarden zijn aanzienlijk lager dan de toegestane maxima. Het is een symmetrisch wiel dus alle 36 spaken dragen bij aan het dragen van de last.

Hoe kan ik dit probleem voorkomen in een nieuw wiel? Zoudt U hiervoor Sapim MG nippel sluitringen aanbevelen (Andra 35)?
Met belangstelling Uw antwoord tegemoet ziende verblijf ik,

mickeg:
I have bought Sapim nipple washers from BikeHubStore. 

I recall seeing that they had Ryde rims at one time, I asked about CSS rims but they did not have any.

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