Longest ride since 2007

Today I took the GRR across the Dumbarton bridge to Fremont, for a loop up the Alameda Creek trail and back to the bridge on Thornton avenue through Newark.

Raft of pelicans feeding on alameda creek

The total distance was 38.2 miles. This was the longest ride I've taken since... flip flip flip through log-book... summer 2007! Then I went 38 miles; between then and now, only a few rides over 20 miles.

The weather today was classic Bay Area summer: a chilly, boisterous sea wind out of the northwest poured fog over the coast range, looking like whipped cream slopping out of a bowl. This was a quartering tail-wind going out, and a quartering head-wind coming back. I used assist level 3 for a couple of miles where the road is at water level and completely exposed to the wind, and for climbing the Dumbarton bridge. Other than that I used level 1 going out and level 2 coming home.

The BionX battery started with a full charge (Joe had charged it up while it was at Velolectric for repair) and ended indicating half-charged. The charge indicator has eight segments. So far, one segment seems to equate to about 9 miles. That's for not-very-hilly rides, mostly flattish with occasional climbs.

If that relationship holds down through the bottom segments of the display—it might not be linear, auto fuel gauges often are not—but if it holds, a full charge should be good for a 70-mile ride. Comfortably over a metric century as I guessed early on.

Regardless, the motor assist is doing exactly what I hoped it would do: make me feel like a strong, confident rider, capable of longer rides again.

Bike fixed - something learned

I found that by folding the rear seats and pushing the passenger seat all the way forward, I could just squeeze the GRR into our Prius. Monday morning I did that and ferried the bike up to Joe at Velolectric. Within a couple of minutes he had diagnosed the problem.

It seems that the motor axle has to be in a particular orientation relative to the frame. The orientation is shown by a small notch at the left end of the axle. This notch has to be vertically down. (click pics to biggenate)

Somehow, the axle had rotated a quarter-turn from this orientation, producing the failure I had. Joe expressed some puzzlement, saying that he was pretty sure he had torqued the axle properly. "The factory says 30 foot-pounds, and I have a torque wrench just for that."

I didn't say then, but I did 'fess up when I returned Wednesday to pick up the bike, that it was I who had loosened the rear axle. It was my fault it failed!

What had happened was that I received an 11-32 freewheel and wanted to install it. I removed the rear wheel, which was no more awkward than before (it is never very easy to get the rear wheel out of a Tour Easy frame) except that it weighs a bit more now.

Then I found out I couldn't get the freewheel off. This is a notorious problem with traditional freewheels, as documented by Sheldon Brown. You need to clamp the tool into the wheel with the axle nuts, then clamp the tool into a vise and turn the wheel... I couldn't get the freewheel to budge, so I put the wheel back in the bike. I didn't notice the notch or realize its significance, but it must have been in the right orientation because the bike worked fine afterward. Joe explained later that the axle is held into the hub by friction of a cone washer, and doesn't move easily even when the nuts are off.

However, I certainly didn't tighten the axle nuts to 30 ft/lb. I probably tightened it using the Easy Racers triangle-shaped socket wrench, with about 4 inches of leverage. I have strong wrists so probably put, oh... 15 ft/lb? or so ... on the nuts.

Forty miles later, about, coming downhill on regen braking on a bumpy road, the axle rotated a little bit and there we are.

OK, all fixed. But this opens a up a whole new question: suppose I have to change a flat rear tire? The only tool I carry on the road is a little multitool that incorporates a crescent wrench.

Thirty ft/lb torque off that? I don't think so. Flat tires are very rare with modern bike tires but they do happen. Well, if one does, I can perhaps lie on my back on the road and give the wrench a shove with my foot.

Longer ride - and a failure!

Today I took the longest ride I've done in quite a while. Not so very long, just 32 miles, from Palo Alto out through Woodside to the Pulgas Water Temple and back.

Returning via Mountain Home Road (a pretty, woodsy road that passes some veddy veddy exclusive estates), I engaged the regen brake to slow from 20mph for a stop sign. Just before the bike stopped there was a second of a heavy vibration out of the rear wheel, a jackhammer-y kind of buzz, as if something was clutching and un-clutching rapidly.

And when I started pedalling again—there was no assist. This was more than a bit disappointing as I still had one long and three short hills to climb.

Experimenting I found that if I selected level 4, I could get a bit of assist, but it surged, coming on and off at about 2-second intervals. Better than nothing, but not right. At level 3 there might be a trace of assist; nothing detectable at 1 or 2.

I stopped and checked that all the wires were OK and wiggled all the connectors. Nothing helped. All other functions worked, including the manual throttle (which I employed to get a quick boost over a couple of steep spots). If I had to guess I'd say something in the motor no longer senses rider torque output properly.

Once home I called Velolectric and arranged to bring the bike up to them on Monday. So we'll see.

More early experience

As of today I've ridden with "Bram" the 15-mile loop to the gym four times, and done the 20-mile "Loop" ride twice.

The Loop is a popular ride around here. It has several variations, but basically it is the big sloppy triangle formed by Alpine Road, Portola Road, and Sand Hill Road. I have to ride a few miles to reach a corner of the triangle. And I come home via Stanford Shopping Center to have coffee & a roll at a pleasant cafe whose name I forgetLa Baguette.

Friday's loop ride felt really good. As before, I used assist level 1 most of the time, going to level 3 to climb the three significant hills on this route. Assist or not, I'm already getting stronger as a result of the riding. (Of course, all that will go away again when we spend 2 months in Germany next fall...)

At the start of the ride, the BionX console reported 3/8 charge in the battery. When I left the shopping center for the four-mile ride home, it still had 2/8 showing. I used juice as profligately as I could, level 3 all the way (out-dragging cars at intersections) and even using the manual throttle to golf-cart along the last half-mile, and I still couldn't get it down to the last segment.

But I put it on the charger and topped it up anyway. So today, Monday, starts a new battery-load of juice. About 5 miles into the 15-mile ride to the gym and back, the indicator had dropped to 7/8. But after shutting down at the gym and starting up again to come home, it was back to 8/8, and remained there all the way home. So I don't know.

Early days with Bram the Stoker

I've ridden about 60 miles with my new, electric stoker on behind. Since it's a bit inhuman, and brought to life by electricity, it seems appropriate to name it Bram Stoker.

So, how is Bram as a riding partner?

Weight

Well, for a start, Bram's heavy. The restored bike, before installation, felt "light and tight" to ride. The BionX battery pack weighs about 8.4 pounds (about 3.8Kg); the rear wheel with its hub motor, heavier spokes, and assorted wires adds perhaps another 5 pounds (2Kg). Not a huge amount of weight, but it is enough to make the bike feel hefty and a bit top-heavy when I wheel it out of the house.

Assist Levels

With no assist on, the bike accelerates slowly and would be hard to take up a hill. Or so I assume, since I've not tried climbing any hills with zero assist.

With assist level 1 on, the bike accelerates and climbs approximately like it did before the conversion.

According to the BionX manual, level 1 adds 35% to the rider's own torque output. While I have not yet begun to test this in any rigorous way, I would say it just about compensates for the weight of the motor. Certainly this level does not do anything to keep you from getting a good workout. The thing is, Bram doesn't voluntarily move the bike (unless you operate the manual throttle, described later). You have to apply torque to the pedals before the motor will begin to add its 35% to that torque. In order to feel it, or to get any visible indication on the console ammeter, you have to apply enough torque that would accelerate the bike in any case. Which means, you end up sweating.

There's a tiny bit of lag, maybe a quarter-second, in the motor's response, both starting and stopping. In other words, you apply pressure to the pedals and the motor kicks in a perceptible instant later. Then, when you back off, there's a tiny moment when the motor's pushing and you aren't. It isn't a problem; just noticeable.

Level 2 (the manual says) adds 75% to your efforts. I find myself dialing in level 2 when climbing a steeper hill when I'm fresh, or the other day, coming home from the gym because I felt tired, dammit, and wanted to. Again, you have to put some torque on the pedals, and then Bram adds a very noticeable boost.

I have only commanded level 3 a few times. Last friday I took a route that climbs a couple of significant hills (Sand Hill road east from Portola valley). This, I discovered, is where the 150% boost of level 3 really comes in useful, if you're not in the greatest of cycling shape. I started up the grade and punched for assist 3, and shortly I was yelling "Woot! Wow! This is the way to climb a hill!" I was still working hard, mind you, but the bike just buzzed up the hill. Climbing hills is fun?!? Good work, Bram!

Level 4 is supposed to add 300% to your own efforts. I haven't tried it except once, briefly. I have a hard time imagining when it would be useful.

Throttle Control

The manual throttle is a thumb-lever sticking out of the bottom of the BionX console. Press it when the bike is rolling, and Bram starts pedalling on his own. I've only done it a couple of times. It feels very sinful. I'm strongly opposed to the idea of the bike as an electric motorcycle. This isn't why I'm on the bike.

Range

I'd like to post here how many miles the system will go on a charge. I can't yet. I charged the battery once, when I brought it home. Now, after 60 miles, the battery gauge on the console is still reporting 3/8 charge. Tomorrow I hope to take it down close to the bottom.

Too Low the Gearz!

As I noted earlier, when I replaced the old 52-42-26 chainrings I ordered smaller ones: 48-38-24. That was when I supposed the new rear wheel would use my existing 11-30 cassette.

Well, come to find out, the BionX hub only supports the old-fashioned thread-on freewheel, and not the modern (since, like, 1980) freehub and cassette. This is a major shortcoming in an otherwise well-engineered system. I cannot fathom why they would not have designed the motor/hub as a freehub accepting a cassette.

There is a very limited choice of 8-speed freewheels; in fact, the authoritative Sheldon Brown site advises against even using them. Certainly there are none that have an 11-tooth high gear.

In fact, Joe stocked only a 14-32 freewheel, and that's what was installed. This reduced the top gear an additional 20% for a total reduction of something like a third in the available top speed.

The result is that now I'm spending all my time in the big ring, and I cannot pedal faster than about 27mph—on a downhill where before I could pedal to 35.

The 24-tooth inner ring is just useless, I haven't even tried it. The middle ring is good from about 8 to 20mph, and with the electric assist, I can't imagine a hill that would need the granny.

So far as I can see the only cure is to buy three new chainrings, at least the old 52-42-26 sizes, and perhaps larger. Which will be a bit of an expense. Sigh.

Update: A correspondent at the Easy Racers forum pointed me to comcycleusa.com where they do stock 8-speed freewheels with 11-32 gearing. I ordered one instantly and will post when it arrives.

First impressions

Speed Cut-off

One of the first things I noticed on the ride home was that the motor cut off the assist at 15mph. Below 15mph, when I pedalled, the motor would help. The help was noticeable to my legs, and visible as a current drain on the console. But at 15mph, it cut off.

Reading the manual, it turns out this is a feature; but the speed limit for models sold in the US and Canada should be 19mph. The European models are supposed to cut off at 15 (goodness knows why). I've emailed Joe, and he has replied that this could be changed easily on the bike, and I will make the change as soon as he tells me how.

Assist Levels

When any assist level is selected, the motor cuts in and starts helping as soon as the wheel begins turning. Assist level 1 is just perceptible. Level 2 is quite definitely noticeable, and makes my takeoff from a red light competitive with the average car. Provided I can click-in the SPD cleat on the free foot on the first pedal revolution, I can really zip across an intersection at level 2.

Level 3 gets spooky, and level 4 is just ridiculous—I'm past the 15mph cutoff before I can really appreciate it.

When climbing a hill, each level is worth about one gear. That is, I can climb the hill in the next higher gear, with the same perceived effort, if I engage the next higher assist. Well, I haven't tried climbing a hill with level 4 yet. Maybe it's worth two gears (for a total of 5).

I've only ridden this system on some pretty short and gentle hills: the climb on Foothill expressway from Page Mill up to El Monte, and a couple of freeway overpasses. Tomorrow I think I'll take it up something more demanding.

Generate Levels

I was initially skeptical of the BionX feature of regenerating on braking, but in fact it works quite well. There is a magnet on the rear-brake lever, and a sensor wire from the console sticky-taped near it. When you operate the brake, the console senses it instantly, and does two things: stops assisting (if it was assisting), and starts regenerating at the maximum level. This retards the bike quite noticeably, about like a light brake application, but without the pads hitting the rim.

You can also select regenerative levels 1 (slight) to 4 with the console. You would only do this if you were looking at a long downhill run, or if you wanted resistance training. What a concept: you can make pedalling harder, electronically. Biking not enough of a workout? Turn on a virtual head-wind!

Regeneration is allowed at any speed, it isn't subject to the cutoff speed that applies to assist. Some postings on V Is For Voltage (an active electric-vehicle forum site) suggest that the system will force regeneration above some maximum speed. I haven't had it over 24mph yet, so don't know if that's true.

Range

I can't say much about range yet. One 8-mile level ride with assist-1 on made no dent in the battery-level indicator. A 15-mile ride with a few easy hills and assist-1 or -2 on, dropped the indicator one segment of 8. So it looks good so far; a metric century with assist on should be feasible.

BionX arrives

Tuesday Marian drove me to the Velolectric shop to pick up the completed conversion. Joe Robinson showed me the details.

Then I took a ride around the parking lot.

Everything seemed to work so I rode the bike the 8 miles home, down Middlefield road.

At home I had  closer look. As I expected, the rear rack mount makes a very tidy installation.

The lock visible at the leading edge of the battery holds it in. When the lock is operated by the key, it pops out and then the battery can be slid out of the frame.

You can take it inside for charging, or for security. Or I suppose, you could swap it out for another, charged battery, if you were on an endurance run of some kind.

The back of the battery has a large reflector and one tiny red LED taillight.

This is pretty useless. It doesn't have a blink mode, for instance. BionX could easily have incorporated a 3-LED or 5-LED blinking light in this case at nominal cost. As it is, I am going to have to find a way to reinstall the nice blinker that I bought, below or beside the battery.

The BionX console is readable and informative. (click this or any other picture to enlarge) The arc-shaped pattern in the center is basically an ammeter: lines appear from the right to show current going into the motor when it is assisting, and lines appear from the left to show current being generated by the motor when it is braking.

The big digit 0 on the right is the assist or generate level. Pressing "+A" raises the assist level from 1 to 4; "+G" lowers it. Lowering past zero commands generate levels 1 to 4. I'll talk more about these levels in the next post.

On the left is a speed readout; the motor knows just what speed it's going. The smaller readout below can be set to max speed, time of day, average speed.

Next entry: first impressions of the ride.