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.