zaterdag 30 maart 2013

"Itoigawa Bombers" test ride (aborted)

Left home at 6 'o clock with the intention to do a long ride to test my new 60mm "Itoigawa Bomber" wheels produced by GS ASTUTO and built by the man himself.  As I approached the lakes, misty rain turned into a constant drizzle and the sky turned even grayer above Saitama.  The moment my feet were getting wet, I made a U-turn.  
The ride was too short to put the wheels to a genuine test but my first impression is very good.  For me, this was the first ride on real carbon wheels and the difference with alu rims was immediately felt, that is...they feel very much alive!  Accelerating felt much faster and road vibration was smoothed out beautifully. 
Braking was no issue at all not unlike on aluminum rims.  I followed Tim's advice and aligned the brake pads perfectly parallel to the rim (no toe-ing in).  Descent in mizzling rain felt very secure.  A much needed sense of reassurance for me!  The new black chili tyres obviously helped too.  
  I will need to get used to the lateral flex though when climbing seated or out of the saddle. On the 19% tiny hill leading up Tokorozawa Tsubakimine Elementary School, both wheels were touching the brake pads as I climbed seated nearly causing the back wheel to block.  This is of course easily fixed by opening up the brakes allowing for more clearance with the rims...but still.  On the Dura-Ace C24's this is never an issue even with the brakes set at minimum clearance.   
All in all and even though today's first test ride was only 40km, I am already extremely pleased with my new acquisition.  I am praying now for better weather soon so that I can put them to a real test!   

Tim's very logic comments (excerpt) related to the abovementioned "issue":
It's quite normal for some rim flex
at the brake block. Why? Because deep rim attach the spoke well below
the brake pivot point - so any flex you get is above the spoke
attachment and might contact brake. For narrow rim - even far more
flexible - this almost never happens because spoke attachment point is
close to the brake pad - and regardless the flexing of frame / wheel
will be centered more in the brake. Weird, huh? But if you imagine the
vectors you can see it.

These rim have quite stiff lateral performance - maybe 45-50nm, and my
KOM wheels is very low, maybe 25-30nm - yet KOM wheel won't contact
brake block because it's only 24mm rim depth and spoke attach close to
the brake pad.
Thanks Tim!