(Photos © J. Maus)
Every now and again I come across a bike on the streets of Portland that I feel is worth sharing.
Back in December 2007 we featured Gram Shipley and his scraper bike. Last night, outside the Bike Commute Challenge party at City Hall, I did a double take on a customized old-school mountain bike with an odd brake configuration. A few minutes later, its owner walked up and I realized it was Mr. Shipley yet again.
Gram calls this green beauty his “4-by-4” because it has four brakes and four chainrings. It’s a steel, 1985 Mirada (made by Schwinn). The brake levers are made for riders with only one arm an dcan pull two cables each. Gram decided to have a redundant braking system. Each wheel has a cantilever and a drum brake, which means when you pull the levers you have the stopping power of four brakes all at once.
The gearing is another fun feature of this bike. It’s got a 9-speed XTR cassette with four chainrings up front mounted to a set of 180mm Cooks Bros. cranks.
limited to his bicycles.
Gram — who volunteers at the Community Cycling Center and keeps his eye out for used parts — says he built it as an urban assault vehicle that can also tow a cargo trailer (which, of course he plans on customizing as well). Gram’s plan for the trailer is to have a telescoping hitch that pulls a brake cable as it compresses.
With its massive Fat Frank tires, the 40 lb. bike is ready for anything. Gram rode it in RAGBRAI this year, but he’s got bigger aspirations for the future: “This thing was built to survive the apocolypse — or the economic collapse, or whatever you want to call it.”
See a bit more of the 4-by-4 in the slideshow below:
Thanks for reading.
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“Gram’s plan for the trailer is to have a telescoping hitch that pulls a brake cable as it compresses.”
Gah!
“telescoping hitch that pulls a brake cable as it compresses.”
A surge brake. An excellent idea for a loaded bike trailer.
NOT AN EXCELLENT IDEA!
Has anybody ever pulled a trailer?
The harmonic resonance, the ‘bounce back‘ that happens at certain speeds when a trailer is hitched to your bike would be enough to trigger the brake. I suppose it would happen less with an inline trailer, but those aren’t exactly utility cargo trailers as they get setup for small loads. I’ve often wanted brakes on my trailer but not if it means the trailer won’t work when it bounces.
I’m not saying don’t try it, but i fall in to the categories of people who feel upset about all these front suspension forks taking over where there had been solid frames/forks. I’ll be stoked if any of this stuff ever proves my wrong.
But, watch the next trailer that comes to a bottom of a hill and how that pushes the trailer into it’s bike, wouldn’t this be a problem?
Surge brakes exist in the auto world. They work great. You just have to calibrate the telescoping resistance to the surge force that you want to trigger braking – with an elastomer bumper or a spring or something. Easier said than done, but totally within reach for an avid tinkerer. Great idea for any trailer load over 400 pounds.
With enough damping the resonance could be avoided, albeit the damping would mean the brakes would not be activated without considerable force. This I think is reasonable, though. If the mass being pulled is only 20 pounds, who cares if it brakes? But if is on the order of 100 pounds, then that is when the brakes might be activated and when they will be a huge help.
Same ideas used in suspensions of vehicles, and vital in engineering.
As for being at the bottom of a hill. Once the biker starts going forward, the trailer’s brakes will be on, holding the trailer back and allowing the bike to pull forward to release them. The damping should prevent obnoxious resonances.
I think the trailer with brakes is a great idea, and would love to hear if it is implemented.
40lbs! WOOF.
I hate this bike
Love living in the NW! Bike culture is huge among here along with the arts, music, great food and beer, and overall quality of life. Gram is just one of many bike tinker people up here that are making helping think outside the box of what is possible for the bike. Keep on Gram!
I’m sure it hates you right back there Drew! Did you see that smug look on it’s face?
“bike is ready for anything.”
Are there fenders on the market that can accommodate the generous girth of those fantastically fat tires? (and is there enough clearance in the frame for them?)
Granted getting the trailer brakes to work properly may require some design tweaks and a few test runs, but thats all part of the invention process.
I wouldn’t mind having redundant brakes on my regular bike.
Anyone know where to get some of those dual cable brake levers? One of my customers has one arm badly weakened by polio.
Pyramid Dual Cable Brake Lever
Sunlite has one also.
My bike is nicer, but those gloves!
We just got an email about a brake device of this kind. I don’t know anything about these at all, but here’s the link for your comparison shopping pleasure.
http://www.brakedirector.com/howitworks.htm
CycleTote has sold trailers with “automatic brakes” for years. The BTA has one and it works pretty well. The hitch, when compressed, engages drum brakes. I haven’t encountered any surge effect problems with it.
http://www.cycletote.com/options.html
Go Gram, go! That thing is a delightful freakshow.
i might do this braking system on my motored-bike…
Gram is one talented motherfucker. He can, and does build anything. The man is a creative and engineering genius. Pretty much anything I’ve ever seen him attempt building, in any medium has been golden. Look out for this guy, his visions are so far out that you’ll be trying to catch-up for years and never quite make it.