12 or 13 miles into a ride on the Bacon Slicer today. This is tricky stuff: the 23 mm tyre pumped to 130 psi is so firm that if I rode over a Braille document, I could read it with my goolies. The new 80mm Koxx cranks are fine for cruising on the smooth, but require enormous concentration on anything rougher than a freshly-ironed billiard table. My route has taken me along entirely familar paths around the Water Sports Centre and the river bank, but it has been like my first time off road. A lot of the way, I’ve had a head wind which has eaten into my concentration levels. I’m as tired as if I’d done 12 or 13 miles of proper Muni.
Now, with a following wind, I am whizzing along the canal towpath, which is flat, coated with fine rolled grit, and slightly undulating. Ahead of me is a pedestrian, travelling the same way as me. To my left is a band of stone edging and a 2 foot drop into the canal. I’m cruising at around 11 mph (17 kph). I pass the pedestrian, lose concentration for a moment, start to tip forwards, accelerate out of it and overcompensate - the effect of the smallest movement of the tiny cranks being magnified at the wheel rim.
The wheel starts to overtake me, and I fear falling on my back. I half regain control, then have to bail out to avoid injury. I land upright and the uni skitters ahead of me and over the edge into the canal with a sorry splash.
The 23 mm tyre has virtually no buoyancy, and the uni subsides beneath the surface. Even the seat (standard Miyata) is barely buoyant enough to slow the inevitable descent. I throw myself to my knees and reach for the rapidly fading red blur of the seat cover a few inches below the surface of the filthy brown water, and just manage to catch it in time.
The Bacon Slicer back on dry land; the rider doubled up with laughter born of relief and embarrassment; the pedestrian trying hard not to smirk.
Ride statistics:
Max speed 13.9 mph (22.3 kph)
Distance: 18.3 miles (29.4 km)
Average speed: 8.9 mph (14.3 kph)
Riding time 2:03
Maximum depth (measured at the seat) 8 inches approx. (20 cm)
Decompression stops… not needed, quite. 
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