It’s Mt. Diablo Hillclimb TT time again. Practice 1

My teams annual fundraising event is scheduled for June 27th.

http://www.ncnca.org/ncncaevent/mt-diablo-hillclimb-tt-0

Every year I strive to beat my goal of  29 minutes and last year got within 19 seconds of doing it.  Since last year I have developed a fondness for hill climbing on single speed on my all steel Reynolds 725 Wabi Classic so this year I intend to ride that.

Wabi Classic 725

The Diablo Hill Climb from the North Gate is not an ideal climb for single speed as the gradient varies considerably throughout the course. The first 1.5 miles are not really steep at all and there are a few false flats on the course too.  The solution would be to gear up but unfortunately there are a couple of fairly long steep sections too. My normal climbing gear for Diablo is 42″ when riding single speed. This gives a speed of speed of 12.5MPH at 100RPM which is about 0.5MPH short of my sub 29 minute target.

Comparison of Specialized Tarmac on gears to Wabi single speed 42″

I did a practice attempt on the climb today on 42″ to see what sort of time I could do.  I had ridden the climb a couple of weeks earlier on the Diablo Northgate summit TT so I knew the gear was ok but racing on your own is a different matter. The first mile was horrible, setting off at 110-140RPM and attempting to keep it up was very unpleasant and my average speed was well down on my Geared bike PB. From the chart above you can see that only a mile in and I have lost 35s and continue to lose time all the way up. The only time I was slightly faster on the Wabi was at around 2.9 miles on the steepest section of the climb. By the finish I was a catastrophic 2m34s slower than my Specialized Tarmac time.

The Wabi felt good on the majority of the climb so I was quite shocked to see how much slower it was (I was). I am not sure I could have pushed a bigger gear on the steeper bits but i am going to have to try if I have a hope of getting a respectable time come race day.  The Wabi weighs 2+ pounds more than my tarmac which according to the 7% average grade should equate to about  (http://cdn.velonews.competitor.com/files/2014/08/FASTER_LighterBikePower_Time.jpg) 5 seconds per mile or 30 seconds. I can work on losing 2 pounds body weight before the event but the real time gains will have to come from fitness,  technique and gearing. I plan to try 46.7″ next weekend to see if I can manhandle the bike up the steeper bits. A 42″ gear is roughly equivalent to a 34 x 21 (39 x 24) which is bigger than I would use on the steep bits of the climb if i had gears.  A 46.7″ gear is roughly equivalent to a 34 x 19 (39 x 22) which I am sure will feel quite big.

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