The Wind Cries Tunnel

A boring weekend in the life of 34s, what with our budding NRC star enjoying a well-deserved weekend with her toes in the sand and a fruity blender drink in her hand.  Lacking any local races to do myself, I took my 34s for a 70 mile cruise of the south coast, whereupon I averaged comfortably in excess of 20mph and reconfirmed that if solo centuries were a valid from of racing, my standard of mediocrity would be several levels higher than where it currently stands.

Your guess is as good as ours

In addition to shipping a bunch of wheels (sun shining, hay making, etc) we're currently prepping our next trip to the wind tunnel, which will take place soon.  This will be the first time we've sent a pair of 34s, and we're doing better than sending one - we're sending two pairs.  One of the burgeoning questions around disc brakes on road bikes is how well or poorly they perform aerodynamically.  While the results should stand as a definitive answer for "how does a 24 spoke 34 equipped with disc brakes compare to a 20 spoke 34 equipped for rim brakes," it will be a pretty good proxy for the general question of "what's the aerodynamic cost of disc brakes in on wheels in general?"  The wheel we're sending has a White Industries CLD hub, using a 160mm SRAM rotor.  Tunnel time costing what it does and our interest in this question being enough to send a disc-ready 34 but not enough to exhaustively test every conceivable permutation out there, this will be what we test.  

As we've said a bunch of times, the mandate of the 34s is quite a bit beyond simply being an aerodynamic sensation.  That's way higher up on the job list for 52s than 34s, so while verifying the speediness of 52s before we put them into production was an absolute requisite, it hasn't been so urgent for 34s.

This will also be the first trip that a production 52 has made to the tunnel.  If you'll recall, when we first tested the 52, we sent our pre-production prototype, fondly dubbed Canary Thunder.  Canary Thunder had 24 spokes rather than the standard 20, and was a little rough of finish.  We'll be testing it against the same benchmark 404 that we send last time (same wheel exactly, as correct protocol would mandate), so we'll have a good reference benchmark back to the original test.  This will give us a slightly dirty answer to the question of how 4 extra spokes affects a 52 specifically, intermixed with some noise about how a yellow plastic prototype compares to a full production wheel.  

There will be a few other wheels making the trip, some of which will be making multiple runs to answer more of the world's burning questions, and you can be sure we're going to drag this one out into a bunch of blogs to ensure that any at-work time in July that you're not spending glued to the Tour will be spent glued to this site.  As it should be.

How about that Talansky, huh?  

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Mike – You don't want me to have to put "spoiler alert" on everything, do you?Joe – Our rim manufacturer has tested them to 350*F. Meaning that they will withstand up to 350*F. The shortcoming with any of these tests is that though they prove that the rims can withstand a s**tload of heat, how is that test applicable to someone on a bike? The way they impart enough friction to get that much heat is to constantly drive the wheel while still applying the brakes with lots of force – so much so that the test is not reproducible outside of a test lab because if you tried to replicate it going down a hill, you'd stop. You simply have no idea of the temperature of your rims as you are riding. We're working on a few tests to try and give people a more applicable idea of what that level of heat tolerance implies in terms of real world usage. Going down a nuts steep hill with constant application of brakes is the best way to impart heat into the system. How steep, how long, how heavy a rider, what tires/volume/psi?

Dave K

Joe – You're smelling what we're cooking, roughly. Lab plus practical. No Bluetooth, incidental use of Strava, plenty of data logging.

Dave K

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