Saturday, April 9, 2011
One week with a wooden cargo bicycle
Jeff & I (well mainly I) have now been riding model No.1 for a week and as we become more familiar with it we become aware of it's idiosyncrasies and it's shortcomings. This is enormously educational and has spurred a good deal of discussion about future iterations.
The bike performs excellently overall. It is light, responsive and comfortable. I am most proud of the handling, basically we nailed the geometry and all the hours I spent sweating the head angle/ fork offset/ trail equation were worth it. Todd at Clever Cycles rode it today and said; "It handles better than ninety per cent of cargo bikes out there and beats the pants of a Bullit". And that from someone who knows his cargo bikes. The response on the street has been overwhelmingly positive. Some people have scratched there heads as to the why until I tell them how much it weighs, then they have that 'aha' moment. Ed the Plumber from down the street suggested I take it to someone and have it made out of aluminum.........I guess the whole wood thing was lost on him. I have ridden the little man (68lbs) to and from school three times this week. I discovered I could carry him and keep up with the wife riding the Bakfeits with the electric assist pegged all the way. Not bad considering it has one gear. It's strong too which is good because Jeff has seen fit to jump it of curbs on his late night rambles with Essie. "Haven't bunny hopped it up a curb yet", he says encouragingly at which point I cover my ears and shout lalalalalala!".
On the down side there is an odd sideways judder that occurs when hitting a bump. The whole forward end shimmers like a tuning fork but to the right.....weird. I attribute this to sloppy alignment of the frame. I was also experiencing some wheel wobble particularly when standing on the pedals and negotiating a curve (like climbing up to the Hawthorne bridge from the esplanade). This was largely solved by letting some air out of the front tire as I had over inflated it a tad. From a design perspective a total flat bed cargo area is a pain. You can't just throw something on there and go with out it sliding around and threatening to fall of. Next version will have a nice generous lip with convenient hand holds for bungees and, well, hands. Not including a slot for a d-lock was another forehead slapping 'duh' moment. That too has been added to the list of really obvious things to do next time. Also under discussion are the cut outs on the side panels. My feeling is they add nothing aesthetically and certainly don't save a lot of weight. They either need to go or get more sexy. From a production standpoint cutting all those holes ate up time tool pathing & cutting on the CNC.
What is encouraging is that all these shortcomings are understandable and solvable and that future versions can only get better. For know we take a deep breath and prepare to move forward.
Oh, and also, I swapped out the gas pipe BMX bars for a sweet blue anodized pair in aluminum. Probably shed two pounds right there..........
The bike performs excellently overall. It is light, responsive and comfortable. I am most proud of the handling, basically we nailed the geometry and all the hours I spent sweating the head angle/ fork offset/ trail equation were worth it. Todd at Clever Cycles rode it today and said; "It handles better than ninety per cent of cargo bikes out there and beats the pants of a Bullit". And that from someone who knows his cargo bikes. The response on the street has been overwhelmingly positive. Some people have scratched there heads as to the why until I tell them how much it weighs, then they have that 'aha' moment. Ed the Plumber from down the street suggested I take it to someone and have it made out of aluminum.........I guess the whole wood thing was lost on him. I have ridden the little man (68lbs) to and from school three times this week. I discovered I could carry him and keep up with the wife riding the Bakfeits with the electric assist pegged all the way. Not bad considering it has one gear. It's strong too which is good because Jeff has seen fit to jump it of curbs on his late night rambles with Essie. "Haven't bunny hopped it up a curb yet", he says encouragingly at which point I cover my ears and shout lalalalalala!".
On the down side there is an odd sideways judder that occurs when hitting a bump. The whole forward end shimmers like a tuning fork but to the right.....weird. I attribute this to sloppy alignment of the frame. I was also experiencing some wheel wobble particularly when standing on the pedals and negotiating a curve (like climbing up to the Hawthorne bridge from the esplanade). This was largely solved by letting some air out of the front tire as I had over inflated it a tad. From a design perspective a total flat bed cargo area is a pain. You can't just throw something on there and go with out it sliding around and threatening to fall of. Next version will have a nice generous lip with convenient hand holds for bungees and, well, hands. Not including a slot for a d-lock was another forehead slapping 'duh' moment. That too has been added to the list of really obvious things to do next time. Also under discussion are the cut outs on the side panels. My feeling is they add nothing aesthetically and certainly don't save a lot of weight. They either need to go or get more sexy. From a production standpoint cutting all those holes ate up time tool pathing & cutting on the CNC.
What is encouraging is that all these shortcomings are understandable and solvable and that future versions can only get better. For know we take a deep breath and prepare to move forward.
Oh, and also, I swapped out the gas pipe BMX bars for a sweet blue anodized pair in aluminum. Probably shed two pounds right there..........
Wednesday, April 6, 2011
Model No.1....what we have learned
Now that model No.1 is done and on the road (bar some minor tweaking) what have we learned and how will that inform our process going forward?
1) It works....our plywood & epoxy concept is entirely viable as a way of constructing a bicycle from the point of view of weight, rigidity & resilience.
2) It is incredibly labor intensive even with CNC machining.
3) We are still lacking in ultimate strength & rigidity as witnessed when I rode with Jeff on the front......but not by much. We are closer than we expected.
4) I would rather gnaw my leg off than pull fillets.
5) Jeff & I have achieved a high level of synergy in our collective efforts.
6) We need to get better manipulating metal.
7) We need to figure out how to ensure proper alignment of the frame.
8) The current prototype, even with butt ugly franken-steering and boat anchor bmx handlebars, still weighs only 49lbs which is about 4lbs lighter than a Harry vs. Larry Bullitt (currently the worlds lightest production Bakfiets style cargo bicycle).
test ride............
Monday night we got to the shop early determined to finish. This involved welding which is not our strength but we got it done and brainstormed the quickest way to get the steering hooked up. What we came up with is one of the ugliest junk yard bodges ever but it works. Around midnight we peered out of the shop to see that the rain had stopped. There was no way we were going home without riding it. Jeff's shop is too small and the muddy, potholed track outside was a no-no so we wrapped the bike up in a large brown tarp, lashed it to the top of the Scion, and drove down to the intersection of SE 3rd & Madison in the lea of the Hawthorne bridge. It was perfect, no traffic, no gawkers and a slight incline allowing us to assess handling gently. So how did it perform? Absolutely awesome! The bike has exceeded our expectations by a long shot. The ride is butter smooth, the geometry dialed and the handling confident and predictable. I even rode it some distance with Jeff sitting on it. Jeff weighs in at 180lbs fully clothed and while we were short on torsional rigidity with that load it was still ride-able. Standing on the pedals and riding hard uphill failed to induce any significant noodling of the frame. We have succeeded, first time out of the gate, to produce a functional wooden cargo bike and we couldn't be more excited. I was jumping up and down like a hyper active eight year old. The only thing that failed us that evening was our cameras. Jeff's ran out of batteries and my card was full so we were unable to record the glorious moment. This morning we finally got out on the street with a camera and committed it to film.
In the video Jeff is carrying Essie (75lbs) around Brooklyn. The music track is Fallahi by Hossam Ramzy shamelessly cribbed from the CD Passion Sources on Real World Records.
In the video Jeff is carrying Essie (75lbs) around Brooklyn. The music track is Fallahi by Hossam Ramzy shamelessly cribbed from the CD Passion Sources on Real World Records.
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