Frequently, people ask me about the limit, in terms of grade of incline, that a Cruzbike recumbent bike can climb up a steep hill. I personally have ridden a CB Silvio up short 25% grade sections and recently, during a New York Cycle Club ride, I climbed a fairly long, steep hill with grades ranging between 20-25%. Skill and finesse are required to prevent the front drive-wheel from slipping, but the technique* can be mastered by most Cruzbike riders. (*Consistent, slow, steady pressure on the pedals while leaning forward over the handlebars.)
Here in New York City, since few of us carry clinometers, it is useful to refer to a specific hill and incline that many cyclists know in order to explain how steep a Cruzbike can climb. My hill of choice is the incline on the West Side Hudson River Bikepath, north of the George Washington Bridge, at that place where the path S-curves inland, up and away from the river and begins following right next to the highway. It's an ugly stretch. While the hill isn't long, three things make it hard: it's crazily steep, it's very narrow, it curves tightly at the steepest section, and -- four things -- there's a traffic barrier in the middle of the narrow bike path that you have to squeeze past. Cyclists tend to think it's barely climbable on any bike, let alone on a recumbent bike.
I've climbed this hill on a Cruzbike Quest 20 when the asphalt was slick due to a drizzling rain. And I did not put down a foot. So, I can say with total confidence that this hill is climbable on a Cruzbike. In addition, I point to this example as one of the reasons I like Cruzbikes for extended long rides where you don't have the privilege of choosing your route to avoid the hills.
Several months ago, I was having a conversation with a customer about how the Cruzbike climbs. This guy now owns a Cruzbike Silvio in addition to a Volae Team rear-wheel-drive recumbent bike he bought from me several years ago. We were talking about this hill so we'd have a common reference point. He went out later and measured the hill with a clinometer app that he has on his smart phone. Here is his note.
L___b
10/22/14
Robert,
Recall that you told me that on your Cruzbike you were able to climb that steep climb on the bike trail by George Washington bridge. I've never been able to climb it on my Volae.
Last weekend I measured that hill with my phone clinometer.
The bottom 20 feet or so are at an 18% grade.
The next 20 feet or so are at a 20% grade.
The next 20 feet or so are at a 12% grade.
The top 10 feet or so are at a 21% grade, going around a sharp left hand turn to the flat crest of the hill, and I measured on the outside of the turn where the bike would be.
Now you know exactly what you climbed.
Even though I ran the App calibration sequence, which is a 2-step process turning the phone 180 degrees to cancel out the phone being thicker at the camera end, I found that the app still measured 2 degrees different on the hill depending on which end of the phone was uphill. I measured both ways and averaged to get the numbers above.
This App from plaincode is the only free clinometer App I have found that has an option (still free) to measure in percent grade (after one-time setup in the configuration dialog to switch from degrees to percent) the way cycling people like to do. Plaincode makes their money on paid upgrades for advanced features.
This app is available on Apple, Android, and Windows phones and tablets. Website with links to each of the three App stores: http://www.plaincode.com/products/clinometer/
My ride was a 90-mile round trip from Yorktown Heights to Stinky Cheese on 20th street and back. Their Caveman Blue is beyond way out there. Just enough daylight for it at my all-day, 11 mph rate.
Regards,
J__ L____
(By the way, this same customer set up his Cruzbike Silvio with a Rohloff Speedhub. I'll post a note about that sometime in the near future.)
Have fun, stay healthy, and go enjoy yourself on some steep hills,
Robert
------------
Robert Matson
New York City Recumbent Supply
The Innovation Works, Inc.
copyright 2015 Robert Matson
No comments:
Post a Comment