All web site content except where otherwise noted: ©2024 Bill Bushnell
Background texture courtesy of Iridia's Backgrounds.
Please send comments or questions to the .
GPS track: | GPX |
---|---|
Bike Ridden: | Power Gold Rush |
Distance: | 68.4 miles |
Cumulative climbing: | 5540 feet |
Total Time: | 6:04:49 |
Riding Time: | 4:05:32 |
Avg. Speed (moving): | 16.7 mph |
Max. Speed: | 36.2 mph |
Nominal System Voltage: | 48 |
Battery energy capacity: | 1200 wh |
Gross energy drawn: | 1008 wh |
Net energy consumed: | 739 wh |
Wh/mi: | 10.8 |
Battery Amps-Hour Used: | 19.9 |
Battery Amps-Hour Regenerated: | 5.3 |
Range extension due to regeneration: | 36.1% |
Peak Current: | 40.7 Amps |
Peak Regeneration Current: | 29.5 Amps |
Peak Motor Temperature: | 59.5 C |
Average Motor Temperature: | 32.5 C |
Mount Hamilton: | Results |
LKHC: Mount Hamilton, November 24, 2016 - Since Kevin Winterfield was unavailable to coordinate and no one else volunteered to step into his shoes, this year's climb up Mount Hamilton was timed by GPS but did not count for the overall score.
I had changed the drivetrain on my Gold Rush to use a new motor and controller and wanted to ride it for time, even if it didn't count officially. But the day before the event I discovered that my horn mount had cracked, rendering the horn un-mountable on my bike.
While one might think that a horn is useless on a bike, for this event it is essential if one is to achieve a good hybrid-electric time on the climb without taking undue risk by frequently crossing the double-yellow line to get past groups of cyclists riding socially abreast in the lane on Thanksgiving Day. Without the horn I'd either have to take risks, or I'd have to wait to pass groups when I could see that the opposing lane was clear while not losing too much momentum.
I would ride for time in spite of this setback. With any luck I wouldn't encounter too many dense groups of cyclists on the road. The weather was expected to be dry but cold at the start, and perhaps that would keep people indoors.
So, I rode from home to Alum Rock Avenue and Mount Hamilton Road, riding the first few miles under leg power only so that I would warm up. The hardest part about starting a ride on a cold morning is starting the ride. Once I warm up after the first few miles, I can be comfortable for the rest of the day, provided I don't stop and linger somewhere cold.
I arrived at the starting point with time to spare. Maybe 30 or 40 cyclists in various groups were preparing to ride, but the overall numbers were much lower than in prior years.
As the unofficial start time approached, the time at which an impromptu group had planned to start together, an idea popped into my head: I'd not ride for time and instead take photos of the group on the way up, leap-frogging them a couple of times, at least on the first climb, while the group was still somewhat together. It would be an experiment.
I wouldn't want to interfere or to provide aid to any of the un-assisted climbers. At one point while I was photographing a group, Eric Wohlberg latched onto my tail, but upon being called out by Chris Evans (who was leading the group), he didn't stay on my tail for long. I took care not to provide another opportunity.
The photos I took on the move are more snapshot in quality, but they still give a perspective that can't be captured by a stationary photographer.
I leap-frogged twice, but by then everyone had spread out enough that I couldn't afford to stop again and wait for the group to pass and still arrive at the summit to see the first finishers. I pressed on up the second and the lower part of the third climb before I encountered the leaders, Eric Wohlberg and Chris Evans at Kincaid Road.
For the remainder of the climb I mostly tailed Wohlberg and Evans until near the summit when Wohlberg severed the virtual rubberband connecting him to Evans and crossed the finish "line" about 30 seconds in the lead.
After I reached the summit I immediately descended to Mile 0 of San Antonio Valley Road to take stationary photos of cyclists rounding the corner for the next hour. Alexander Komlik had already claimed the best spot to take photos on the prow of the mountain, providing the unofficial (and excellent) finish "line" photos for this non-event.
In my set cyclists are identified where I knew the names or could discover them (other photos from the Low-Key Hill Climbs series, Strava Flybys, etc.), but many are left un-identified as the majority are other cyclists riding up the mountain that day who happened to get their photos taken as they approached the summit.
Fortunately, weather on the mountain was mild. Wearing 4 layers of clothing, two of them wool, and the outermost a wind shell, I was comfortable in the sun and did not chill.
On the descent I used the regeneration brake to keep my descending speed around 20-25 mph most of the time, not much slower than if I had been descending naturally, yet I was able to recover significant energy.
After I arrived back at Alum Rock Avenue I detoured through Alum Rock Park before returning home across northern San Jose, arriving before 1500.
GPS track: | GPX |
---|---|
Bike Ridden: | Power Gold Rush |
Distance: | 49.7 miles |
Cumulative climbing: | 4350 feet |
Total Time: | 3:10:44 |
Riding Time: | 2:43:00 |
Avg. Speed (moving): | 18.2 mph |
Max. Speed: | 34.2 mph |
Nominal System Voltage: | 48 |
Battery energy capacity: | 1200 wh |
Gross energy drawn: | 943 wh |
Net energy consumed: | 785 wh |
Wh/mi: | 15.8 |
Battery Amps-Hour Used: | 18.5 |
Battery Amps-Hour Regenerated: | 3.2 |
Range extension due to regeneration: | 20.8% |
Peak Current: | 34.1 Amps |
Peak Regeneration Current: | 36.1 Amps |
Peak Motor Temperature: | 90.4 C |
Average Motor Temperature: | 31.7 C |
Los Altos Hills Climbs: | Results |
LKHC: Los Altos Hills, November 19, 2016 - I awoke at 0445 and couldn't get back to sleep. The prior evening's weather report for Los Altos Hills was not promising fair weather, and when I quickly checked upon waking to see if the report had changed, I saw that it hadn't.
But, when I poked my head out the door I saw stars above and dry roads below. So, I decided to make preparations to ride, do a final weather check, then make a final call.
Earlier in the week I had considered leading a group on the climbs, waiting at the top for everyone, and making sure no one got lost. But, that was a fair weather plan on a day (or at least a half-day) when one could be assured of not chilling while waiting at regroups.
At 0700 I checked the weather report again. Bands of rain showed west of San Gregorio, but the storm front did not appear to be moving inland over the Santa Cruz Mountains with any sense of urgency. Most of the wet stuff was falling north of the Golden Gate. Experience has shown that this kind of storm ends up getting mostly blocked by the local mountains, Los Altos Hills being on the leeward side.
I decided to go, but it would be a fast circuit with minimal stopping. If I was to set good times on the climbs I would need dry roads. Riding before the storm seemed the best way to accomplish that.
As I left home I enjoyed the warm sun on my back. Roads were dry, but to the north the sky looked dark.
This last week I reconfigured my Gold Rush to use a new motor controller and silent direct-drive hub motor, as with the Pursuit, the bike I had ridden on this year's prior Low-Key climbs. This would be the Gold Rush's first outing using the new power drivetrain. I had hoped to finish the reconfiguration process earlier, giving me enough time for a test ride before the Low-Key climb, but I needed more time to finish my work.
Fortunately, everything ran smoothly. Aside from needing a slight rear derailleur adjustment that I did on the fly and a slightly stiff chain link that worked itself out over the first few miles, the bike operated well and gave me no trouble.
As I ran through the course, the weather gradually deteriorated. At first I enjoyed tiny water droplets swirling in the gusting wind, then slightly larger droplets. But, for the most part the roads remained dry.
I could occasionally see blue sky overhead, and at all times when I had a view to the north I enjoyed the company of a pretty rainbow.
After I finished the last climb up Altamont Road, I tried to take the bike path off Edgerton Road that Dan had put on the return route to the start. But, I could not find the start of the path he had intended, finding only driveways at the bottom of Edgerton. I didn't want to end up in someone's back yard or to get lost in the search, so I returned to Altamont Road and descended via Briones and Via Ventana to Page Mill.
I found the Wallace Stegner Path, but that looked a bit too muddy. And, earlier having had to pass horseback riders on the road with great care to avoid scaring the horses, I did not want to encounter any on a narrow trail or path.
I learned later that the path veers off one of the driveways at the bottom of Edgerton, so I'll have to return to try again.
As I descended Page Mill Road I passed the LGBRC group just starting out, and lower down I encountered Frank Paysen, Marek and Mel Dutkiewicz. Later at Elena and Purissima I encountered the LGBRC group again where I managed to get decent snapshots of most of them.
The dampest I got was near home as swirling mist became a steady drizzle.
Overall it was a successful outing, and the bike didn't even get dirty.
GPS track: | GPX |
---|---|
Bike Ridden: | Power Pursuit F2 |
Distance: | 83.6 miles |
Cumulative climbing: | 6640 feet |
Total Time: | 6:41:26 |
Riding Time: | 4:39:33 |
Avg. Speed (moving): | 17.9 mph |
Max. Speed: | 44.1 mph |
Nominal System Voltage: | 48 |
Battery energy capacity: | 1600 wh |
Gross energy drawn: | 1214 wh |
Net energy consumed: | 1028 wh |
Wh/mi: | 12.3 |
Battery Amps-Hour Used: | 23.4 |
Battery Amps-Hour Regenerated: | 3.6 |
Range extension due to regeneration: | 18.1% |
Peak Current: | 36.9 Amps |
Peak Regeneration Current: | 35.7 Amps |
Peak Motor Temperature: | 72.3 C |
Average Motor Temperature: | 39.4 C |
Tunitas Creek Road Climb: | Results |
LKHC: Tunitas Creek Road, November 12, 2016 - For the second week in a row I rose early, but not quite as early as the prior week's ride out to Livermore. I took a direct route to San Gregorio via Old La Honda Road, then through the fog and drizzle on Skyline, the chilly forest of La Honda, and out into the warm sun in San Gregorio. I rode at a moderate pace as I had extra time, and not knowing the weather at the coast, I didn't fancy sitting around at The Bike Hut any longer than necessary. My fears of cold, damp weather were unfounded.
As I climbed Stage Road I ran into Andrea Ivan who appeared to have survived her adventure last Saturday, riding up Mount Hamilton from Livermore and back.
We continued to The Bike Hut, where other Low-Key'ers were gathering for the climb up Tunitas Creek Road.
When it was time to get started we all promenaded up Tunitas Creek Road as far as Lobitos Cutoff Road, the same start location as our slightly longer climb in 2009, when we finished at Swett Road and Skyline Blvd. In 1997 the climb started a couple hundred yards in from CA1, so times from today's climb are not directly comparable.
After a short speech from Dan Connelly the horn was honked, and we were off.
Because the E-Bike category scoring handicap is severe on courses with flatter terrain, I rode as fast as I could on the flatter, lower portions of the course.
Above Lobitos Creek Road the county roads crew had recently laid down a tar and gravel job. Gravel stood on the road in places. Most of the time the extra gravel caused only disconcerting crunching noises under my tires, but at one spot near the top I fishtailed momentarily. I don't think I could have ridden it faster and still allowed for opposing traffic in the corners.
After I crossed the finish line I returned a hundred yards down the road and set up for shooting photos. Light was fairly uniform on my subjects, but the backgrounds featured some blown-out highlights. The overall light level was low, and my camera had to crank up the gain so that I could use 1/320 second for most of the shots. A larger lens or a more sensitive sensor would help, but I had to use what I had.
None of the photos is excellent or good, some of the photos are OK, but a significant number lack resolution due to noise, noise reduction, cropping, or some combination of the three. Most of these are best viewed un-zoomed with an impressionistic mindset.
I included at least one photo of everyone in the event. Some participants got two OK photos, and I included both when they were available.
After the event I rode north on CA35, then descended CA92 to Canada Road without much concern for maximizing regenerated energy—On the downhills I coasted up to the bike's terminal velocity or natural regeneration speed—and took the scenic route home through Portola Valley and Los Altos Hills.
GPS track: | GPX |
---|---|
Bike Ridden: | Power Pursuit F2 |
Distance: | 126.3 miles |
Cumulative climbing: | 8260 feet |
Total Time: | 11:01:25 |
Riding Time: | 6:57:37 |
Avg. Speed (moving): | 18.1 mph |
Max. Speed: | 36.6 mph |
Nominal System Voltage: | 48 |
Battery energy capacity: | 1600 wh |
Gross energy drawn: | 1865 wh |
Net energy consumed: | 1351 wh |
Wh/mi: | 10.7 |
Battery Amps-Hour Used: | 37.8 |
Battery Amps-Hour Regenerated: | 10.4 |
Range extension due to regeneration: | 38% |
Peak Current: | 34.5 Amps |
Peak Regeneration Current: | 36.2 Amps |
Peak Motor Temperature: | 85.2 C |
Average Motor Temperature: | 45.2 C |
Mines Road Climb: | Results |
Mines Road + San Antonio Valley Road Climb: | Results |
LKHC: Mines Road, November 5, 2016 - After seeing that Mines Road was on this year's schedule, I knew this would be an interesting climb. Not only is the climb long, but it is also very gradual over most of its length. Moreover, if I planned to ride to the start from home, I'd have to put in a decent-length ride before the event, some of it in the dark.
After the climb the logical return home would be over Mount Hamilton, so I was pleased to see the "6x" climb up San Antonio Valley Road, the "backside" of Mount Hamilton, added as a bonus climb.
The morning of the climb I rose early and was out the door at 0615 before even the faintest suggestion of sunrise glowed in the east. There was something exotic and a bit mad about starting a long bike ride in the middle of the night. It had been a number of years since I had embarked thus.
The roads were quiet near home, but as I continued across north San Jose I noticed the traffic density increase. As I left the suburbs and started up Calaveras Road, the eastern sky began to glow.
Calaveras Road itself was quiet. No auto passed me traveling in my direction, but traveling opposite I saw several.
At Calaveras and Felter one large sign warned of Calaveras Road being closed to traffic during business hours on weekdays, another warned that the road was closed. If I had discovered the road closed at the county line, I would not have enough time to ride around the long way to arrive at the start in time. It was not until I reached the county line and coincidentally saw a small group of cyclists riding the other way that I could be sure the gates had been opened for the weekend.
Temperature started at 9C at home, then warmed to 15C near Calaveras Reservoir, then dropped to 5C in Sunol Valley. I kept moving and didn't stop to put on another layer.
At I-680 I took the ramp onto the freeway, but the lanes for CA84 heading toward Livermore were coned off. A CHP car with its lights flashing was parked ahead, so I rode up to the car's window to inquire if it was possible for me to get through.
I learned that CA84 was being repaved this weekend, and that the entire road was closed. I was further informed by the officer that I was not allowed to bicycle on the freeway.
I attempted to explain that bicyclists are allowed on freeways unless signs are posted otherwise†, that no prohibition had been posted on this section from Calaveras Road to CA84, but it was to no avail. My explanation didn't fit with the officer's simple black and white view on the matter, and he stubbornly maintained that bicyclists are banned from all freeways without exception.
"You see that sign that says, 'End Freeway 1/2 mile'?", he pointed ahead. "That means you can't ride your bike here. This is a freeway."
"Freeways are for cars and trucks," he added.
Whether or not I was able to convince the officer that bicyclists were permitted on this section during normal times, I would have to turn back this morning due to the repaving project. So, I turned around and rode the shoulder against traffic back to Calaveras Road.
Instead of a straight shot over Pigeon Pass into Livermore I would have to ride through Pleasanton, adding about 15-20 minutes to my trip. Fortunately, I had some slack in my schedule, so I would not be late.
I continued through Pleasanton then took Vineyard Road east to Vallecitos Road. Then I took the southern route across Livermore, stopping at South Livermore Avenue to eat a snack and to check the Low-Key Hill Climbs web site for the actual check-in location. But with my distance-vision contact lenses I could not read the black text against a dark blue background on my smartphone screen.
I was about to continue on at least as far as Mines Road and Del Valle Road when a group of LGBRC cyclists heading for the start passed me. I followed them and assumed they were riding to the start.
We assembled at a turnout near the bridge over Arroyo Mocho. After making our re-acquaintances, we assembled again on the far side of the bridge to be released in small groups.
After the first few miles of climbing Mines Road levels off and contours for several more miles, dipping and rising occasionally. At maximum power I found my speed too high to safely negotiate the blind corners, a couple of times having to slow suddenly to allow a different line through the corner due to rocks or gravel on the road.
At the fourteen mile mark the road resumes a gradual climb alongside Arroyo Mocho. A number of sharp curves counseled caution, but where I could see within my stopping/maneuvering distance that the road was clear I applied full power.
A few miles from the summit I passed Janet and Dan in the car. Fortunately, they caught up to me as I crested the summit, so I figured they had marked my finishing time.
After taking a brief moment to catch my breath, I walked a hundred yards down the road to find a good spot to take photos.
The best photo spot was on the opposite side of the road under a digger pine laden with mace-like pine cones. Fortunately, no wind blew.
To get the same motion blur with a zoomed lens from the opposite side of the road I used a faster shutter speed than I use with a wide-angle lens. 1/400 second seemed to be about right.
After the last Low-Key'er had passed through I rode down to The Junction Bar & Grill for lunch, coasting slowly around 20 mph to maximize regenerated energy.
My fast ride up Mines Road had consumed much battery energy, as I had expected. I had arranged with The Junction to use one of their outdoor 120VAC outlets to charge my battery enough to keep me out of the worry zone.
This all worked initially.
I flipped the adjacent switch to "On" and plugged into the outlet on the wall. The battery began to charge.
But I noticed that the switch also turned on a set of outdoor lights, four that I could see, but possibly others. I thought perhaps the switch controlled only the lights. I attempted to flip the switch to "Off", but it would not click into the "Off" position. So when I went inside to place my lunch order and to introduce myself. I told the woman behind the counter that I had accidentally turned on the outdoor lights and that the switch wouldn't go off.
"Oh, don't worry about it. I'll fix it. The switch is sometimes stubborn," she added.
So, I waited with other Low-Key'ers enjoying lunch, then ate my lunch and relaxed for a short time. Meanwhile I had not checked on the progress of my charging.
When I was ready to depart I walked over to my bike and discovered that the charger was off. I checked on the battery's charge, and learned that only 1/2 Ah had been added during lunch. I had expected somewhere around 6-7 Ah.
I realized now that either the switch controlled both the lights and the power outlet or that my charger had tripped a breaker. The latter was less likely as my charger draws only 400 watts.
I could remain at The Junction to get the charge I expected, but then I'd be racing darkness at the end of the ride, and I'd have to fuss with the sticky power switch and possibly enlist help from the overwhelmed Junction staff—the place was busy serving many customers— to debug the problem. Or I could depart now and get home on the energy I had in the battery. I calculated that I would have enough to get home, but I'd have little margin. The battery would be nearly depleted.
I decided to depart and take my chances. The next time I needed to charge at The Junction I would monitor the process more often.
So that I'd have enough battery energy to pull full power up the final climb to the summit, I conserved battery energy on my ride south through San Antonio Valley and down Arroyo Bayo, using more leg energy than I would have otherwise.
When I got to the bottom of the bonus climb I stopped for several minutes to recover before making the final push. I observed "three dots" on my battery gauge, which was enough to get me to the top. But would I be able to pull full power for the entire climb, or would my system reduce power as battery voltage fell below a critical 44 volts?
In the end I was able to pull full power until one mile before the summit, where my controller rolled back power to keep the battery from falling below 44.0 volts. By the time I crested the summit I was able to pull only 600 watts from the battery. My time up the climb would not be my shortest.
I continued across the ridge to the summit of Mount Hamilton to enjoy the hazy view to the west. While I waited, other Low-Key'ers, Adem, Andrea, and Rupesh arrived. I also spoke with some other folks who had seen me elsewhere along the road.
Andrea was starting to fade and was hoping to call her sister to collect her from somewhere between the summit and Fremont, but her sister didn't answer her phone. Andrea had started in Livermore, so her return distance would be similar whichever direction she chose to go, through San Jose and Sunol or back along the course via The Junction.
I advised her that if she thought she might be caught by darkness—she had left her headlamp in her car—that it would be safer on lightly-traveled Mines Road than on the roads between Sunol and Livermore. I wonder how her day ended.
My battery was nearly depleted, but I was not worried about my battery running flat as I had over 4000 feet of glorious downhill over which to regenerate. Yet, by the time I got home my battery was almost as depleted as it had been at the summit of Mount Hamilton.
On the usually uneventful ride home through north San Jose I glimpsed something unusual in the sky: the left half of a sundog, a halo consisting of an image of the sun refracted through ice crystals high in the atmosphere. When I got to the top of the Trimble Road bridge over US101 I stopped to photograph both halves, the right half of which was barely visible.
The remainder of my ride home passed uneventfully.
†See the following for more information:
Caltrans FAQ
Google Street View of I680 ramp
Google Street View image of CA84 ramp confirming that bicyclists are expected at this location
GPS track: | GPX |
---|---|
Bike Ridden: | Power Pursuit F2 |
Distance: | 93.4 miles |
Cumulative climbing: | 8440 feet |
Total Time: | 9:53:43 |
Riding Time: | 5:49:24 |
Avg. Speed (moving): | 16.0 mph |
Max. Speed: | 33.4 mph |
Nominal System Voltage: | 48 |
Battery energy capacity: | 1200 wh |
Gross energy drawn: | 1361 wh |
Net energy consumed: | 981 wh |
Wh/mi: | 10.5 |
Battery Amps-Hour Used: | 27.1 |
Battery Amps-Hour Regenerated: | 7.6 |
Range extension due to regeneration: | 39% |
Peak Current: | 80.0 Amps |
Peak Regeneration Current: | 25.6 Amps |
LKHC: | Results |
LKHC: Old Santa Cruz Highway, October 22, 2015 - My approach to the start of this week's climb took the shortest route from home. I thought that the last part on the trail alongside Lexington Reservoir might be muddy due to the recent rains, but I was happy to find the trail in reasonably good shape, although a few short sections were borderline gumbo. If we hadn't had several days of dry weather, those sections could have been messy and slick. The hardest part of the trail was getting my bike past the barrier at the end.
The start crew let me go a minute ahead of Group 1. Due to the shortness of the climb I was hoping for several minutes of a head-start to give me more time to find a good photo shooting spot near the top of the climb, but as it was I had just enough time to get ready for the first finishers.
Hazards on this climb were two stop signs along the route, both of them monitored by course marshalls, and an unexpected Recycling Day at Holy City, where we could expect to find more than the usual traffic. These were also monitored by course marshalls. As it turned out none of these presented any problems. Thanks to Will von Kaenel, Lynn Sestak, and the rest of the Los Gatos Bicycle Racing Team for pulling this off. My biggest challenge was getting past other cyclists who were just riding up the road and couldn't move out of my way between the moment they heard my approach and when I was upon them.
After I crossed the finish line, I returned down the course to find a spot that offered reasonably good conditions: giving me some warning before cyclists passed me, space on the shoulder for me to park my bike and to sit, and usable if not good light.
On the latter point, the light was not as good as for the Highway 9 climb. Subjects were in shadow and backgrounds were bright. I was able to compensate enough in post-processing, but the results are not quite as good as when light is ideal. Photos are a bit more grainy, and light/dark boundaries are slightly fuzzy and prone to fringing. They work well enough if you don't zoom them too much.
If I had had more time to set up I would have continued further down the road to a spot that offered light similar to that on Highway 9. But, if I had tried to reach that spot this time, I might have missed the first finishers.
I kept the lens wide and the shutterspeed near 1/200 second, drive mode in continuous shooting, and focus in continuous tracking mode.
After the LKHC event I rode into Santa Cruz via Soquel-San Jose Road, spending a couple of hours with my sister, her partner, and her two large dogs. By the time I left her house I was covered in dog hair, hair that somehow managed to detach itself from my clothing by the time I got home.
I explored one new route on my return from Santa Cruz. As I rode Mount Hermon Road into Felton, I did a U-turn at Covenant Lane—no left turn across a double yellow line—then turned right on Sycamore Lane. At the first junction I turned right and descended to Woodwardia Road that I took to its old wooden bridge over Zayante Creek. The bridge is closed to auto traffic, but is apparently still open for bicycles or pedestrians. This cuts off a large loop into Felton or an even more adventurous loop on Covenant/McAdams/Hihn/Bahr/Moon Meadow/West Zayante. I doubt it saved much time, but it was nice to get off the main road for a while.
As I was climbing Zayante Road I lost one of the bungee cords holding my left side panel. This particular cord had come detached in the past, so I was not surprised to make this discovery, but I was slightly annoyed with myself for not discovering the loss before I had reaached the top of Upper Zayante Road. I turned around and descended about a mile in a fruitless search for the missing bungee cord. Failing to find it, I rigged a temporary closure, then continued toward home.
I did not have enough battery capacity to climb Zayante twice, and as it was the battery was nearly flat by the time I crested Castle Rock Summit. But, I did not worry as I had over 2000 feet of descending to put some charge† back into the battery, more than enough to reach home from Saratoga.
†I maximize regeneration on the descents by using the regen brake to keep my speed under 50 kph and can recover about 1.25 Amps-hour per 1000 feet descended. Energy recovery per unit distance is constant (as near as I can measure) between about 25 and 50 kph. I suspect the efficiency of the motor and controller used as a generator increases as speed increases, compensating for the additional aero losses within this speed range. Outside of this speed range energy recovered per unit distance declines measurably.
GPS track: | GPX |
---|---|
Bike Ridden: | Power Pursuit F2 |
Distance: | 89.7 miles |
Cumulative climbing: | 7740 feet |
Total Time: | 7:36:44 |
Riding Time: | 5:14:26 |
Avg. Speed (moving): | 17.0 mph |
Max. Speed: | 41.6 mph |
Nominal System Voltage: | 48 |
Battery energy capacity: | 1200 wh |
Gross energy drawn: | 1309 wh |
Net energy consumed: | 950 wh |
Wh/mi: | 10.6 |
Battery Amps-Hour Used: | 25.6 |
Battery Amps-Hour Regenerated: | 7.0 |
Range extension due to regeneration: | 37% |
Peak Current: | 34.0 Amps |
Peak Regeneration Current: | 22.4 Amps |
LKHC: | Results |
LKHC: Highway 9, October 8, 2015 - The climb up CA9 from Saratoga to CA35 is more gradual than the prior week's climb up Montebello Road. I did not expect the bike to run into difficulty on this climb, and I was not surprised on that count.
I was pleasantly surprised that I managed the climb in under 20 minutes at an average speed of just over 20 mph. This speed allowed the direct-drive hub motor to operate in its most efficient zone, its maximum temperature staying below 70C all the while.
I use this climb as a test climb up Highway 9 when testing e-bike drive systems and modifications. The grade is long and fairly constant, and even lower-powered hub motors have just enough torque not to stall on its grade. When I do these tests I never pedal as doing so would confound any results with my pedaling input. But today on the LKHC event pedaling is strongly encouraged, and I pedaled as vigorously as I could.
When I climbed this hill recently with this very same power system in its current configuration, without pedaling, the motor overheated once near the top of the climb, and I had to wait 5 minutes for it too cool down before resuming. The moving time on that occasion was 44 minutes, more than twice as long. Human power input makes a significant contribution on a climb like this by adding just enough additional power to the system to keep forward speed in the motor's efficient zone, which allows more motor power to be converted into forward motion and less into heat. The effect is one of positive feedback.
I reached the top of the climb just as Cara Coburn was crossing the finish line. After chatting briefly with her and others, I descended a couple tenths of a mile to a large turnout I had espied earlier from where I snapped the other participants' photos as they rode by.
Light was good. Although I was aiming the lens nominally toward the sun, direct sun was shaded by trees. Sunlight on the road acted like a diffuse reflector lighting the faces of the cyclists, and the sunlight filtering through the changing big leaf maples cast a pleasing background glow.
Today I slowed down the shutter to 1/160-1/250 second. I used the faster shutter for the faster riders passing early on, and the slower shutter for the slower riders so that, to the degree that I could create the illusion, all riders would appear to be traveling as fast past the camera.
Not all faces are as crisply in focus as I would like, and this I attribute mostly to the subjects bobbing or otherwise moving relative to their bicycles. To judge whether I tracked my subjects well, examine the degree of blur on non-rotating parts of the bicycle.
As a roadside spectator one tends to focus on the leader of a small group of cyclists riding together. On this occasion, and with mixed results, I made an effort to get good shots of the wheelsuckers.
After the LKHC event was finished I continued south on CA35, then Summit Road and down Soquel-San Jose Rd. toward Soquel. I was planning to drop-in on my sister who lives in Santa Cruz, but whe was busy, so I modified my route and turned toward home.
While riding down into Los Gatos I descended Mountain Charlie and Old Santa Cruz Highway, a route featured by LKHC later in the season. I discovered that the roads were in the same condition they were the last time I had ridden them and that there did not appear to be any reason to think this would change before the actual event.
Instead of taking Old Santa Cruz Highway down to Bear Creek Road and then CA17 into Los Gatos as I usually do, I descended Aldercroft Heights Road to Alma Bridge Road and rode the long way around the reservoir before joining CA17 and dropping into Los Gatos.
While I was regenerating (20-25mph) on the descent to Alma Bridge a couple of autos caught up to me and followed me down to the bridge, a descent that took about a minute. The lead auto turned right into Aldercroft Heights, but the second followed me onto Alma Bridge Road then pulled alongside.
Its male driver yelled something unintelligible out the open passenger-side window, then sped ahead before I could respond or acknowledge. After the auto pulled ahead an arm emerged from the driver's side window, its fist held high. I waved back in a friendly manner, and again an arm emerged. Its fist jutted violently upward in a "Power to the People" gesture. I waved again, this time more broadly, and the auto roared off.
At this point it occurred to me that the driver might have intended a gesture of obscenity rather than one of solidarity. Maybe he had unusually small fingers. If so, I wondered briefly what my "offense" had been.
Over the last 10 years I have witnessed fewer incidents of rudeness or road rage (as opposed to incidents of incompetent driving) directed at me as a cyclist, making occasions like this notable exceptions. I continued home reflecting with some amusement on the exchange.
GPS track: | GPX |
---|---|
Bike Ridden: | Power Pursuit F2 |
Distance: | 87.6 miles |
Cumulative climbing: | 9180 feet |
Total Time: | 9:14:54 |
Riding Time: | 5:16:29 |
Avg. Speed (moving): | 16.6 mph |
Max. Speed: | 34.8 mph |
Nominal System Voltage: | 48 |
Battery energy capacity: | 1200 wh |
Battery energy drawn: | 1452 wh |
Net energy consumed: | 981 wh |
Wh/mi: | 11.2 |
Battery Amps-Hour Used: | 28.6 |
Battery Amps-Hour Regenerated: | 9.2 |
Range extension due to regeneration: | 47% |
Peak Current: | 22.4 Amps |
Peak Regeneration Current: | 26.6 Amps |
LKHC: | Results |
LKHC: Montebello, October 1, 2016 - The night before the climb I decided to see how a direct-drive (DD) hub motor would manage on this benchmark climb. In all prior years I have used a geared motor that applies power at the bottom bracket and uses the bicycle's gears so that I could be assured that the motor was operating efficiently and applying maximum power.
Over the last few months I've been fine-tuning the performance of a Nine Continents M3006RC direct-drive hub motor, a relatively inexpensive hub motor made in China sold for export. After switching to a high-quality field-oriented programmable controller, injecting ferro-fluid (Statoraid) into the magnet-stator gap, and attaching heatsinks (Hubsinks) to the exterior motor shell, I discovered that this system runs more efficiently overall than my geared motor on all but the most demanding terrain.
The most difficult terrain for a direct-drive hub motor involves steep climbs at low speed. Just how steep and low one can go depends on the winding configuration of the motor, the applied power, and the motor's ability to shed excess heat.
For the Low-Key Hill Climbs I limit input power to 1000 watts, and this results in reasonably efficient operation up to about 10% grade, where I can keep my speed above about 15 kph. On steeper stuff the motor can't maintain speed and slips into a less-efficient operating zone. (i.e. The motor becomes a heater.) Without the ferro-fluid and heatsinks the motor would quickly overheat.
Montebello Road has some sections that exceed 10% grade, but fortunately, these sections do not persist without breaks. There are easier sections over which the motor can "recover" (cool down) while running at higher speed that see more air flowing over the heatsinks.
If one judges efficiency only on the climb, then the DD hub motor is less efficient than the geared motor. The key to high overall efficiency is to recover energy on the downhills, an amount that usually extends my range from 15 to 30%. On this occasion, due to the high climbing density and my willingness to descend at a relatively relaxed speed of 35-40 kph most of the time so as not to lose too much energy to air friction, I was able to recover enough energy to extend my range almost 50%, a figure I did not beforehand believe was attainable.
On this first occasion running a DD hub motor I was somewhat concerned with the first mile of the climb where the grade exceeds 10%. I did not want to block other cylists. Fortunately, I was able to pull ahead of the leaders on the first couple of switchbacks and not become a rolling roadblock, although I did bog down on the steepest part of the climb about 1.6 km from the bottom, which is why I could not quite beat my time from last year when I rode my geared motor limited to 1000 watts input. Only by applying vigorous human power input was I able to make progress on the steepest parts of the climb.
In spite of that I was pleased overall with the system's performance. Motor temperature rose to a maximum of 70C, well within its normal operating range up to 100C.
After the climb I descended to the bottom and then proceeded on a loop that checked road conditions on two climbs scheduled for later in the season.
The photos were more of an afterthought this week. I found a spot near the top that offered a view of the valley below. I set shutter speed high, but in spite of that, many of the photos were slightly out of focus. Whether due to the high shutter speed or the shallow depth-of-field, the camera's tracking focus had trouble tracking the subjects, especially as they passed before the bright background that offered a view of the valley. Only a few of the images turned out as I had intended. I had to fall back to my backup images in most cases, and these had the subject farther from the camera, resulting in loss of resolution when the image was subsequently cropped. Don't zoom the images too much.
All web site content except where otherwise noted: ©2024 Bill Bushnell
Background texture courtesy of Iridia's Backgrounds.
Please send comments or questions to the .