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We’ve decided on a new research methodology – ride until something breaks.  Then fix it and ride some more.  Over this summer we’re taking the bike out on tours designed to see what weak links still exist for our solar vehicle in order that we can do a major ride when the sun starts nearing the solstice around May, 2010.

Our plan for August 8th  was simple – just ride out under solar power from my front door and go deep into the Sacramento delta.  Until something breaks, that is.

It was fun zooming down the Capitol streets, past the state Capitol building, in fact, and over the Tower bridge into West Sacramento.  This time we were testing how we could operate with a chase car, and our friend Carol drove behind us, a great convenience.  We know we’ll sometimes have chase cars on our long drive next year, but needed to see how we could communicate.  Using FRS radios we were able to stay in touch nicely.

A couple of miles along we heard some rubbing noise on some tire but couldn’t place it.  We stopped, and after a quick survey decided to press on for brunch at Carol’s, a funky little 1950s diner in hard-scrabble West Sacramento.  It was hot as blazes in the sun, but earlier in the week I had fabricated a stoker heat shield made of lightweight Reflectix, a R-11 rated aluminized foam.  Under it I was as cool as under the shade of a tree – not so Russell.  His cycling position is under one of the solar panels, whose backside in full sun is almost too hot to touch.  When under way, though the breeze is wonderful and the machine ran great.

As we stopped for brunch we faced the first of what will probably be hundreds of issues around our vehicle’s security.  Should we just leave it out back, away from view in the restaurant parking lot?  Though we knew it would probably take an electrical engineer and a schematic for someone to just ride off with the beast, I was more worried about valuable bits which any urchin could just pry off – our video camera, cycle computer, light system.  Probably the entire bike could be disassembled if one had a single 1/4″ socket wrench.  So we decided to trundle the 23-foot-long beast in front of the restaurant’s plate glass windows, where we watched as various passers-by did a double-take.

After lunch we did a good once-over of the bike and that rubbing sound.  Russell’s sharp eyes, ever-alert for any asymmetry in the universe, noticed a trailer wheel was cupping to one side.  The damned spokes were loose.  Nearly all of them.  And we had just tightened them the morning of the ride.  What was happening?

On closer inspection we soon discovered that we had broken two spokes on the right trailer wheel.  That left 26 spokes, and I could almost feel the punishment they would be taking on the bumpy Delta roads.  Those little 20″ BMX rims I always thought were a weak link in our design, needing to support a 300-pound trailer with just 28 spokes. I thought we would have to abort our ride in West Sacramento then and there.  No bike shops were anywhere nearby, and a wheel rebuild was probably a weekend project.  But none of us wanted to stop riding.  The sun was so strong that our batteries remained completely charged and the road south beckoned.    But the warped wheel meant the tire was rubbing on a part of the frame and Russell could already see the appearances of tire belts poking through the abraided rubber.

Eventually we decided to do an ad hoc wheel build on the side of the road, hoping to tighten the remaining spokes into shape once again.  Amazingly, as Russ tightened each spoke the wheel straightened up and when he was finished the tire no longer rubbed.  Now maybe we can go ahead.

Soon the industrial wasteland of Jefferson Boulevard gave way to the South River Road, winding along the west side of the Sacramento River, a beautiful and rural snaking path.  We passed miles of grapevines near Clarksbert and we were able to open up the throttle and see what the bike could do.  Carol measured us from behind at a solid cruise of 23 miles per hour.  It felt like it.  The busted up old levy-top road shook us in our seats like a vibrating massage chair.  The air was hot but  it felt lovely as we passed the smells of wine grapes, humus, river muck and hot pavement.  For the first time on these test rides I fired up my talking GPS unit, a clever bit of blind access technology by Sendero Group out of Davis, just ten miles further west.  The GPS system called out every point of interest in its robotic voice as we zipped past.  From 23,000 miles in space I got confirmation that we were really travelling at 22 or 23 miles an hour.  I had wondered how I would be able to use the device without some sort of desk.  Turned out that if I made the neck strap short enough I could rest it on my ribcage while cycling semi-recumbent, yet still type a query or two while in motion.   Things were working.

As we sailed along, past pear orchards, marinas and horse ranches I would query Russ about the bike’s performance.  Amazingly, though we had run flat out for nearly one hour, our onboard battery voltage hardly dipped at all.  The SunPower panels were pumping in hundreds of watts and kept our reserves topped off.  We began the trip with a fully-charged system voltage of 40.4 volts; deep into the Delta our system was still 39.1 volts.  And we were using only around 900 watts full-out, exactly the output of our solar panels. Amazing.

Just around Courtland we felt something funny with our ride and it turned out we had a flat tire.  The same right trailer wheel Russ had straightened now had some sort of flat, just where one of the broken spokes entered the wheel.  No problem.  We jacked up the trailer, took off the wheel and I installed a new tube and we were off in half an hour.  On to the Ryde Hotel.  We thought.

Just a mile after the tire repair the bike still felt wobbly.  “Check your rear tire for pressure,” Russ asked me over the onboard communicator.    We stopped, I reached behind me and the tire was rock hard.  So we proceeded, but this time the bike felt strange and wobbly again.  “Let’s stop at the first shady stop we can,” I suggested, and a half mile down we pulled into a parched grassy area to check things out.  “Hey Bryan, look – one of the hub motor spokes is broken,” Russ said.  “And another and another, and …God, there are a zillion spokes broken.  Come look.”

Russ was strangely happily excited as he often is when he finds another failure mode.  I was instantly sober.  I didn’t want to look. I knew this meant that today’s ride was over.  We didn’t have any of the specialized #12 spokes the hub motor needed, and we didn’t know how to repair things even if we had them.  While Russ was talking on about how nine of the 11 broken spokes were on one side of the wheel and wasn’t that fascinating my mind was racing about what we would do now.  Just then Carol walked over from our chase car and pointed out that the tire we had fixed a mile back had already gone flat.  And also our bike’s right front tire also seemed to be instantly flat. Why all of a sudden these flats?

We looked at the tires and found they were studded with dozens of strange thorns.  The cycling gods were  really telling us we were done for the day.

So we hatched a plan.  Russ would drive out to Elk Grove in the chase car, pick up our flatbed trailer and we’d tie our limping vehicles onto it and…then what?  None of us were ready to leave the heart of the Delta, with its lush farmlands and new terrain for us.  The South River Road was amazingly quiet and traffic-free, maybe more interesting a ride the than our usual American River bikeway.  So we decided to spend the night at the nearby Ryde Hotel, a fascinating 1927 landmark in the middle of nowhere.

While Russ was getting the trailer I strolled down the road to have a pee.  When I returned I looked at my biking sandals and found that their bottom rubber was impaled by at least 50 of those odd thorn balls.  What were they?  Turns out that we’d had our first introduction to the dreaded goathead thorn, also known as puncture vine and a variety of bicyclist explectives.  Our final turnoff under the shade tree could have been a goathead nursery – the ground was covered with the low shrub which we instantly grew to recognize and detest.  A little internet research told us that the vine probably originated in drier parts of southern Europe or central asia and the mideast.  It is an exotic now spreading across the western and southern US, a horrible bit of nastiness which so far can only be removed from specific areas with direct weeding or spot pesticides.  The region it is spreading into is exactly the region we plan to cycle thousands of miles in – the intermountain West.  Clearly we’ll need to find some mechanical barrier to protect our tires from this scourge.  The Tioga Comp-puls we’ve been using are excellent tires, very little rolling resistance, but are a magnet for thorns.  So for future rides we’ll either use some protective tube strips or perhaps invest in beefier tires such as Specialized Armadillos or the Schwalbe Marathon Plus.  Yes such solutions will be heavier and roll less smoothly compared to the Tiogas, but the pain of changing multiple tires every day just isn’t worth it.

More challenging is our need to understand how we broke 11 12-gague spokes on the Phoenix Racer hub motor.  Was the washerboard road surface too hard for the spokes?  Are we running too much weight on the hub motor drive wheel?  Had we neglected regular maintenance of the wheel by not tightening the hell out of the spokes every day?  After all, we hadn’t tightened them at all in the year we’d had the hub motor.  Should we run the tire pressure at maybe 60  psi instead of 80 to soften the ride?  This is what we’ll need to figure out in upcoming months.  We did get what we wanted, though – a day of lovely riding until something broke.  “The trick in what we’re doing,” I told Russell, “Is to be sure that when we break down we do it in a beautiful place.”

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