September 25th, 2009

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.”


September 25th, 2009

Us and building

Us and Maker Fair sign

For weeks we’d been anticipating our large public debut at the Maker Fair, a massive exhibit of creations by nearly 600 home inventors from around the world.  Held in the San Mateo County fairgrounds south of San Francisco, the fair has grown in its past eight years to a Bay Area happening attracting some 80,000 home DIY-ers, tinkerers, artists and alpha geeks.

The organizers of the Fair, associated with Make Magazine, couldn’t have been nicer to us.  They provided us with parking and a lovely conspicuous outdoor spot in full sunshine. So Saturday morning we found ourselves on a lush grass lawn at  the end of one of the big buildings, near the bike technology zone. Across the road from us was a coal gasification device. On the other side of the walkway was a robot group from a catholic college. They had diving robots in a backyard pool. This was a good location, as we had southern exposure for the panels, and visibility from three sides.

Overall view from north

Many interested visitors

There was a lot of visitor traffic. There were also interesting vehicles wheeling past, one of which was a solar powered quadracycle. A neighbor cycled by on a fully suspended recumbent trike he had made, and had them for sale. The fun vehicles inspired us to take rides around occasionally. This was a good idea, since we then got more exposure, gauging by the exclamations.

It was strange to ride at such slow speed parting through the thick crowds, and thrilling to have them appreciate this. We used the bell and horn a lot, though we weren’t obnoxious. Everyone expected the next strange contraption to pass by, piloted by eccentric inventors. We got a lot of serious interest on these excursions, but couldn’t talk for as long as when we were stationary. We would hear “…solar bike…solar?…it’s solar…” as we passed by.

Trike and Bryan

Bry guy and panel

Bry chatting with folks

Bryan, being more gregarious, handled the people with many questions and long discussions. He had a chair with shade, and could hang out and talk at length. Russell took the opposite end of the trike, waiting until people had read the posters and had questions. We passed out many of our flyers with specifications. Russell is the type who would read first and ask questions later, but some people are the opposite, and we could handle either type.

People near posters

For the posters, we had a block diagram of the electrical system, a spec sheet, and the drawing of us as hot rod monsters. It all said what needed to be said. People could take the 8 1/2 by 11 flyers from a table. It was gratifying to see groups of fans having technical discussions, pointing at the posters and designing their own solar vehicles on the fly.

Interested visitors squatOthers peered at the mechanisms, absorbing information that way. Such people often had very specific questions. Where else but at the Maker Fair could one have random conversations about battery chemistry, charge controllers and the aerodynamic advantages of bike fairings?  We were surprised by how many technical tinkerers had thought about building a solar bike but couldn’t quite get things together.  This year…

We were also tickled by the warm culture of helping and gifting among the exhibiting inventors.  One guy from Canada lent us a portable sound system he’d designed expressly for electric bikes.  We strapped it onto our trailer and would add loud solar-powered music to the din of the crowd.  Later on we learned that the audio amplifier he designed will be available to any ebike running 20-72 volts through The Renaissance Bicycle Company in Vancouver, B.C.  It’ll be a wonderful thing to have music on board when we take our long ride and enjoy music when we camp.

There were hundreds of fascinating people and projects we came to know over the long weekend, but one in particular matched the spirit of empowering science education we embrace.  Kevin Norman of the Berkeley-based ‘Science Whiz’ holds a series of summer camps to teach youth how to make their own electric bikes.  At the end of each week’s session the student emerges with a working bike of their own.  Remarkable. And even more remarkable is that one week’s session designs and funds a small solar-charged electric bike.  If you know a kid who would be dazzled by this challenge they would really enjoy going to: www.sciencewiz.org

People pointing at trailer

Guys tended to be the technical ones, explaining the device at hand to their girlfriends. Though we did talk to one woman who made electrified bikes and trikes, and was asking some detailed questions as to how she might incorporate solar power. Russell has installed Exploaratorium-style science education exhibits at Burning Man, and has found the same guy-explains-tech-to-girlfriend phenomenon. Its something the guy can do, and in the best of situations, is seen as endearing and enhancing closeness.

Family at posters

It was gratifying to see so many kids brought there by their parents. Here, three generations share interest. One little kid was crawling on his hands and knees, asking what this and that was. As Russell explained the solar charging scheme, the child understood immediately, repeating back his verbal formulation of what had been said. He could have been six or seven. The kids being at the faire indicates what kind of parents they have; the type who teach technical thinking early. There are probably both innate and learned aspects to this kind of thinking, which flourishes when natural ability is augmented with mental discipline. Making a project that has to work is the best discipline I can think of.


July 10th, 2009

In mid-May the folks at SunPower invited us to attend a major Silicon Valley bike-to-work day event held at the SunPower campus in San Jose. The afternoon promised to be full of dignitaries and biking enthusiasts. Russ and I looked at each other and realized that after years of tinkering and test rides this SunPower bike-to-work day would really be the first public debut of our little machine.

There was an awful lot to do to get ready. Our video camera to read the Outback charge controller was swamped by too much sunshine. We needed to finish wiring up the power supply for our stoker-to-captain communicator. An important shade panel over the stoker’s seat had to be cut and mounted. Both front and rear derailleurs had to be re-adjusted after we had earlier dismantled them. And we had to figure out how we could mount a special protective chain guard to the rear crank so that we didn’t accidentally shred the foot of some Silicon Valley dignitary.

But more bothersome was the dreadful surprise we got one week before we were set to take the bike to San Jose. All along our plan had been to rent one of those 6’ x 12’ enclosed trailers from U-Haul and tow it behind my Ford Explorer. We’d even designed the bike and solar trailer so that it wouldn’t be larger than the magic 11’ 7” interior length of the trailer. With careful alignment we figured we could nest the bike and trailer side-by-side inside the U-Haul, lash both down and be off and running to exhibits like the one at SunPower.

Imagine our shock when the U-Haul guy told us that his company wouldn’t rent its enclosed cargo trailers to be towed by, of all things, my Ford Explorer. I had towed a 2,000-pound popup tent trailer with the very same vehicle for years with no problem. Now we were trying to tow about 450 pounds of payload in an otherwise-empty trailer and U-Haul wouldn’t allow it. Turns out, the manager explained, someone once overfilled a U-Haul cargo trailer and while speeding in a Ford Explorer overturned and there was a fatility. After the ensuing lawsuits were settled, U-Haul, a strange privately-held firm, made the corporate decision not to rent its cargo trailers to those using Ford Explorers. Oddly enough they would rent to the same vehicle if it had the Navajo designation. The lawyers had won. We had one week to figure out how to get the solar touring bike the 120 miles from Sacramento to San Jose.

I briefly thought we could just buy an enclosed cargo trailer of our own, but I soon discovered that ones of the size we needed sold for $4,000 and more, even used. More than we were willing to spend on our out-of-pocket project. As the bike-to-work day got nearer, I cruised Craig’s List for some wheeled device which we could use. I learned about the universe of ‘toy haulers,’ designed to carry ATVs, motorcycles quads and all manner of recreational things. Amazing trailers, some even with living quarters above, with amazing prices as well.

At the last moment up popped an old 6’ by 12’ flatbed landscaper’s trailer, the ones you see gardeners using. It was perfect, especially because its 5’ rear gate could be used as a loading ramp. And at $600 it was a steal, with new tires, axles and bearings.

The day before the event we drilled some I-bolts into the floor, padded some contact points and carefully loaded the bike and trailer onboard. Would it fit? To our horror we discovered that the actual size of the flatbed was about half a foot smaller in all dimensions than the 6’ by 12’ we had assumed it was. We did some careful geometry, though, and found a way we could load the bike and trailer onboard. With the trailer and bike noses protruding a bit off the front of the trailer we slowly closed the back gate. We were amazed. There was just two fingers’ width of clearance. We were home free.

I was a bit leery if we could safely tow the whole rig at 60 mph with the large solar cell area open to the wind. Would the trailer become unstable? Would it rattle things loose? We had, after all, designed the bike and trailer for our nominal 20 mph cruise speed. But Russ was more sanguine. He’d towed bikes, canoes, kayaks and all manner of things on his Subaru roof. Everything was possible with enough lashing.

So we loaded up the trailer with precisely 11 straps, each one with a 2,000-pound working capacity. “That should be sufficient,” Russell said. And it was. We have a certain adjective we use on this project whenever we want something fastened down to absurd tightness. Things are ‘Russellized’ in this manner. I see it all the time. After he’ll borrow my toothpaste I’ll need a vice-grip to remove the cap. Same thing with anything else that turns, like a spigot or a butterfly nut. Now with the 11 1-ton straps the precious solar cargo was lashed down and ready for the road. The wheels would fly off before our solar bike.

trailered up rear

Our improvised trailer transport system worked beautifully.

Our improvised trailer transport system worked beautifully.


The trailer and bike towed like a dream. We were in San Jose ahead of schedule, and Russell’s strap design was so good that in ten minutes from our arrival we had rolled off the bike and solar trailer, connected the electrical systems and were ready to go. As we did a test ride around the SunPower parking lot we realized that something was making a repeating loud grinding noise. It turned out to be the protective foot disk we’d installed on the stoker crank, just a bit too close to the motor drive chain when under drive. It made our sleek quiet machine sound like an embarrassing squeaky shopping cart. We scoured our toolbox for something we could press into service to fix the scraping sound and we found that a strategic bit of electrical tape would quiet the racket…or at least until we got back home to make the proper fix. Five minutes later we were again whooshing along silently.

As we cycled in the noon sunshine we realized that the SunPower panels had finally made it back to where they had originated in 2008. We heard employees chuckle to see the very panels they had been installing on rooftops now zipping along on our strange contraption. We got lots of hi-fives and laughter. We also got stuck in a small hill of newly-plowed dirt we had tried to cross to get to the event. SunPower employees helped push our bike backward onto the blacktop so we could take our place just next to the main stage.

Our bike’s first public debut at the SunPower San Jose headquarters.  We were at the green tech ground zero, admired by CEOs and  tycoons.  We had a blast.

Our bike’s first public debut at the SunPower San Jose headquarters. We were at the green tech ground zero, admired by CEOs and tycoons. We had a blast.

Soon we met Bobby Ram, the first SunPower executive we came to know, an early believer in our project. Bobby was delighted to see our recent improvements in the bike and trailer and he soon was bringing other executives over to have a look.

SunPower Vice-President Bobby Ram  sits at the controls of our bike.

SunPower Vice-President Bobby Ram sits at the controls of our bike.

We spent a good amount of time chatting with San Jose Mayor Chuck Reed, a strong supporter of the development of alternative energy. Mayor Reed asked us some technical questions about the motors and energy budget for the bike and was very upbeat about the prospects for solar electricity in San Jose, the nation’s 10th largest city.

San Jose Mayor Chuck Reed talks about solar energy with Russ and Bryan.

San Jose Mayor Chuck Reed talks about solar energy with Russ and Bryan.

Because Silicon Valley has one of the world’s largest concentrations of green technology companies it wasn’t surprising how upbeat Mayor Reed is on renewable energy. His top ten goals in the next 15 years are impressive indeed. Here they are:
Green Vision Goals
Within 15 years, the City of San José in tandem with its residents and businesses will:
1. Create 25,000 Clean Tech jobs as the World Center of Clean Tech Innovation
2. Reduce per capita energy use by 50 percent
3. Receive 100 percent of our electrical power from clean renewable sources
4. Build or retrofit 50 million square feet of green buildings
5. Divert 100 percent of the waste from our landfill and convert waste to energy
6. Recycle or beneficially reuse 100 percent of our wastewater (100 million gallons per day)
7. Adopt a General Plan with measurable standards for sustainable development
8. Ensure that 100 percent of public fleet vehicles run on alternative fuels
9. Plant 100,000 new trees and replace 100 percent of our streetlights with smart, zero-emission lighting
10. Create 100 miles of interconnected trails

Mayor Reed wasn’t the only visionary executive at the bike-to-work day. Tom Werner, SunPower’s CEO, spent time examining our bike with his company’s donated solar panels. Werner is a huge bicycling enthusiast, regularly riding to work and staying fit. As he looked over the bike I thought of a challenge. “Hey Tom,” I asked, “Would you be willing to race against our bike and your own solar panels?” He paused for a moment and then asked, “What’s your top speed?” When I told him 22 mph he chuckled and told us he didn’t think he could outlast his own panels. We agree. In strong sunlight our panels produce the power of three Lance Armstrongs, an unfair advantage against a lone CEO. We took this opportunity to thank the entire SunPower team for their support and enthusiasm.

SunPower CEO Tom Werner,(l)  an avid cyclist, admires his firm’s panels on the solar touring bike – but gamely declined to race against us.

SunPower CEO Tom Werner,(l) an avid cyclist, admires his firm’s panels on the solar touring bike – but gamely declined to race against us.

After all the speeches, after all the questions and answers when the crowd thinned out and went back to work, Russ and I took a quick quiet ride in the neighborhood just to enjoy the pleasure of it. The bike was smooth, the weather perfect. We’d designed a way to take our little machine to shows and exhibits, important because in just two weeks we were set to spend a long weekend showing off what we made for 80,000 attendees at the Bay Area Maker Fair.

Love your blog!

April 2nd, 2009

Bryan & Russ:

Cool new blog!  Keep up the good work.