So you need new rims

Velocity Rims-1050116After only one year of riding the Velocity Blunt SLs they developed cracks.  At close investigation the cranks are only on the drive-side.  It’s never boring in Bike Land.

It’s time to replace the hoops and reconsider weight, stiffness and satisfaction.  A quick call with one of most respected wheel builders in Germany, brought forward a few options:

The big difference between the rims above and the Velocity Blunt SL I was using is a mere 40-50 gram as the SLs are advertised at 420 g.  I had to scratch my head and ask myself can 40 gram makes such a difference?  I also thought that an interesting option, in the same price range, would be Kirk Pacenti’s SL25.  The rims weight 450 gram, are 24.5mm wide and measure 26.0mm high.  So I contacted Kirk and asked for his opinion.  Within a few hours Kirk responded recommending the use of different spokes than the ones I used so far (Sapim CX-Ray) and pretty much assuring me that even with the style of riding the wheels endure, I should have no problems.  After all, these rims were used by Mark Beaumont to ride clear across Africa – these roads could not have been better maintained than the paths I take around here.

Kirk’s note also sent me to the Sapim website to check out some data points.  It turns out that the CX-Ray weight 272 gram for 64 pieces at 260 mm.  They are rated for strength at 1600 N/mm2.  The D-Lights come in at 307 gram while the Race model weights 363 gram.  Both D-Light and Race, however, allow for “only” 1300 N/mm2 of tension.  As the good folks at Sapim write on their web site, “high tension is always better.  The higher the tension the stiffer the wheel.”  So back to said wheel builder we go and entrust him with making the right decision on building a wheel that’s stiff, light and robust enough to cary my rather large skeleton.

So here we have it, loads of data, but the real question is still open – what wheels to build.  The discussions seems like a rabbit hole, especially since one can easily find articles such as these that dissect at great length the concept of wheel stiffness.  Decisions?  Since Kirk is such a nice guy and I am interested in trying his SL25 rims out, I’ll go with these.  This is by no mean a statement about the rest of the options.  I rode H Plus Son for a while, but they are not Tubeless compatible and suffer from the “been there” syndrome.  I rode a lot of Velocity rims and managed to kill all of them.  So it’s really time for something new.  And new, as we know…is always…better.

One Comment

  1. Reply
    Alex November 3, 2015

    Hey J,

    what about eyelets, which distribute the spoke load a bit better on the rim?

    and of course: the most important Q: what would Jobst say (Jobst Brandt)?

    A

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