Mavic EX721 Rim - Probably Not for Touring

After reading a few reviews about the Mavic EX721 rims I came to the incorrect conclusion that they would be would be ideal for our expedition bicycles. Shortly after purchasing the rims, I read several reports of the rims failing when used as for touring. blah!

So trying to make the best of the situation, I reasoned that if we followed the manufacturers' specifications for spoke tension, tire pressure and width we shouldn't have any issues with the rim. Below is the tension, pressure and width that we used for our wheels:
  • Spoke tension set to a maximum of 90 kgf, if lower, was within 20% of 90 kgf
  • Tires were the Schwalbe Marathon Mondial 2.15 inch wide (above the minimum recommended width)
  • Tires were never inflated over the maximum recommended pressure of 55 psi 
In an attempt to further strengthen the wheels we used the triple butted, DT Alpine III spokes. We also have disc brakes which would be less likely to cause deterioriation of the rims.

Despite all our precautions, after 5000 km the sidewall of my rear wheel rim cracked. Of our four wheels it was the one supporting the largest amount of weight.   
  My cracked rear wheel

The other three wheels were are also built on the Mavic EX721 rims and still appear in good condition after 10 000 kms.

A Selection of Cycle-tourists Reports of Cracked Mavic EX721 Rims

There are many other reports of cracked Mavic EX721 rims that I have not included in the above list. However, I have also read several reports of different rims failing prematurely while touring. In conclusion, more research is required before I rebuild our wheels for our next trip.

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