Bike seat
- Thread starter HAROX
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Ypedal
100 TW
200 lbs. i would not risk my own 200 lbs ass on that .. rear rack mounting hardware is not suitable for much over 50 lbs imo..
MikeFairbanks
100 kW
I hope those ladies in sandals don't hold too much value for their toes.
Man, that looks like an accident waiting to happen.
And what about the bikes? Even if the rack can hold it, the weight limit on most bikes is a little over 200 pounds. Maybe if a couple jockeys ride on one it'll be okay. Most husband/wife combos are going to run about 175 + 125 or so (if they are in shape). That's 300 pounds, not counting the rack, backpacks, etc.
I'm not clicking on the pledge button.
Man, that looks like an accident waiting to happen.
And what about the bikes? Even if the rack can hold it, the weight limit on most bikes is a little over 200 pounds. Maybe if a couple jockeys ride on one it'll be okay. Most husband/wife combos are going to run about 175 + 125 or so (if they are in shape). That's 300 pounds, not counting the rack, backpacks, etc.
I'm not clicking on the pledge button.
Chalo
100 TW
It looks like a sturdy enough steel frame mounted not to the rack eyelets, but the bike's rear axle and seatpost (or seatpost collar). Mechanically, that can be made strong enough for the job. The trouble lies in the bike frame and the wheel to which it's attached. Most are not structurally sound enough to withstand such an unusual extra load without problems.
I have a Redline Monocog that might do the job. It has big beefy plate dropouts and generously sized steel frame tubing. Even in that case, I''m not so sure.
Most frames don't have what it takes, which is why they typically suffer bent axles and dropouts when folks attach axle pegs and carry riders on them. Hefty BMX type dropouts, and hubs with 14mm axles, and skirt guards (for toes) would be wise features to combine with a rack like that proposed above. To be frank, I don't think most folks would bother going to the necessary lengths to make this rack right, especially when for a similar overall cost they could just use an Xtracycle Free Radical instead.
Chalo
I have a Redline Monocog that might do the job. It has big beefy plate dropouts and generously sized steel frame tubing. Even in that case, I''m not so sure.
Most frames don't have what it takes, which is why they typically suffer bent axles and dropouts when folks attach axle pegs and carry riders on them. Hefty BMX type dropouts, and hubs with 14mm axles, and skirt guards (for toes) would be wise features to combine with a rack like that proposed above. To be frank, I don't think most folks would bother going to the necessary lengths to make this rack right, especially when for a similar overall cost they could just use an Xtracycle Free Radical instead.
Chalo
As an aside: Probably the rack is strong enough to hold the static weight claimed. The problems come with shock loading from bumps, and the wiggling/twisting/yawing/etc loads back and forth on all the joints and connections while pedalilng or turning, anythign that adds side forces.
Every rack that failed me (built by me or bought or found, etc) with a load on it over the years, both long before and after motorizing my bikes, did so during some type of shock loading, when the energy of changing G forces (usually vertical from potholes or bumps) multiplied the equivalent weight on the rack from far below it's max loading to what may have been several times it's max load.
Most of them failed at some joint, usually where they bolt together the rack to the vertical supports, often with visible stress fractures where they had been bent side to side repeatedly under load from swaying motions of the rack, despite all hardware being tight. Sometiems it was a collapse of the side vertical in a front-to-back fashion, crumpling in the middle.
At various points over the years I've modified racks to add triangulation to those points, preferably as an X across the side vertical supports, with the point of the X just over the rear tire, and the beams going as far down as possible. A curved arch can also work, but I only tried that one once with some pieces I already had from something else, that happened to be almost the right length and curve for the purpose--but it had occasional tire rub on sidewalls cuz it wasn't quite wide enough or stiff enough.
Every rack that failed me (built by me or bought or found, etc) with a load on it over the years, both long before and after motorizing my bikes, did so during some type of shock loading, when the energy of changing G forces (usually vertical from potholes or bumps) multiplied the equivalent weight on the rack from far below it's max loading to what may have been several times it's max load.
Most of them failed at some joint, usually where they bolt together the rack to the vertical supports, often with visible stress fractures where they had been bent side to side repeatedly under load from swaying motions of the rack, despite all hardware being tight. Sometiems it was a collapse of the side vertical in a front-to-back fashion, crumpling in the middle.
At various points over the years I've modified racks to add triangulation to those points, preferably as an X across the side vertical supports, with the point of the X just over the rear tire, and the beams going as far down as possible. A curved arch can also work, but I only tried that one once with some pieces I already had from something else, that happened to be almost the right length and curve for the purpose--but it had occasional tire rub on sidewalls cuz it wasn't quite wide enough or stiff enough.
friendly1uk
1 MW
Chalo said:It looks like a sturdy enough steel frame mounted not to the rack eyelets, but the bike's rear axle and seatpost (or seatpost collar). Mechanically, that can be made strong enough for the job. The trouble lies in the bike frame and the wheel to which it's attached. Most are not structurally sound enough to withstand such an unusual extra load without problems.
I have a Redline Monocog that might do the job. It has big beefy plate dropouts and generously sized steel frame tubing. Even in that case, I''m not so sure.
Most frames don't have what it takes, which is why they typically suffer bent axles and dropouts when folks attach axle pegs and carry riders on them. Hefty BMX type dropouts, and hubs with 14mm axles, and skirt guards (for toes) would be wise features to combine with a rack like that proposed above. To be frank, I don't think most folks would bother going to the necessary lengths to make this rack right, especially when for a similar overall cost they could just use an Xtracycle Free Radical instead.
Chalo
If it is indeed sat on the axle, then the frame and dropout's have an insignificant part to play.
Anyone have data surrounding wheel strength? As kids if we gave a lift on a racer, the back wheel generally failed. It was not a done thing. However a bmx could land such a weight off a curb, and I have seen video's of tricksters dropping off roofs. I just don't know what sort of weight a mountain bike wheel will take.
Most bikes say around 100kg, but that's all bikes. On a racer, they mean on smooth ground. On a mountain bike, they mean crashing it. It's no guide to what a wheel might take. I bet spokes are rated in a manner that might help...
Chalo
100 TW
Single vertical rack stays only work in a few limited circumstances, where a relatively rigid rack top is firmly affixed at two or more points so it can't yaw.
In most circumstances, vertical stays should form a V (as viewed from the side). It also helps stability if one of the pairs tapers inwards when viewed from the back. The Tubus Cargo rack is an example of everything done pretty much the right way:
It has that arch Amberwolf was talking about, but it is less the arch and more the A-frame that the stays form that contributes stability to the rack. It's also made of tubular chromoly steel, which is a great material choice. As a result, the rack is rated for 88 pounds-- more than any other bicycle rack I am aware of.
But a rack does not have to be nearly as optimized as the Tubus Cargo to be plenty stable, if it has four solid mounting points to the bike frame. Three solid points aren't nearly as good, and four points where two of them are soft (as when mounting a rack on a racing bike or suspension bike, with p-clips) are worse yet. In those situations, the rack must provide its own rigidity the way the Tubus Cargo does.
In most circumstances, vertical stays should form a V (as viewed from the side). It also helps stability if one of the pairs tapers inwards when viewed from the back. The Tubus Cargo rack is an example of everything done pretty much the right way:
It has that arch Amberwolf was talking about, but it is less the arch and more the A-frame that the stays form that contributes stability to the rack. It's also made of tubular chromoly steel, which is a great material choice. As a result, the rack is rated for 88 pounds-- more than any other bicycle rack I am aware of.
But a rack does not have to be nearly as optimized as the Tubus Cargo to be plenty stable, if it has four solid mounting points to the bike frame. Three solid points aren't nearly as good, and four points where two of them are soft (as when mounting a rack on a racing bike or suspension bike, with p-clips) are worse yet. In those situations, the rack must provide its own rigidity the way the Tubus Cargo does.
chalo i agree. The A frame is king. It may have precedence over/under the arch, in construction. The Tubus is much more well designed. Well then, Tubus is the winner in this weeks' special question from the barnyard..Chalo said:...a V (as viewed from the side) helps stability, if one of the pairs tapers inwards when viewed from the back. The Tubus Cargo rack is an example of everything done pretty much the right way:
and it is less "arch" and more "A-frame" that contributes stability to the rack.
if it has four solid mounting points to the bike frame. Three solid points aren't nearly as good.
Sketch o' rama.
The seat mounting point will tug at the seat post tube, potentially snapping it if there is enough weight hanging off the poor thing.
Also, why is the rear rider raised up so high? this is the worst place for center of gravity! You want your rear rider as low as possible!
And since bikes are designed for one person, do they really think any ordinary bike would just happily take two riders on the back of the bike?
Yuba's Boda Boda is much better.
Xtracycle edgerunner would be best
The juicedriders ODK would be great as well. I rode one the other day with the electric setup - not bad!
The seat mounting point will tug at the seat post tube, potentially snapping it if there is enough weight hanging off the poor thing.
Also, why is the rear rider raised up so high? this is the worst place for center of gravity! You want your rear rider as low as possible!
And since bikes are designed for one person, do they really think any ordinary bike would just happily take two riders on the back of the bike?
Yuba's Boda Boda is much better.
Xtracycle edgerunner would be best
The juicedriders ODK would be great as well. I rode one the other day with the electric setup - not bad!
The ODK, that's great! Your Bomb is beautiful. I actually started grinning on your ride.neptronix said:Sketch o' rama.
Yuba's Boda Boda is much better.
Xtracycle edgerunner would be best
The juicedriders ODK would be great as well. I rode one the other day with the electric setup - not bad!
Side note: You might could use some "A frame" mojo on the bomb, so you can fill the void under the seat with amps. That said, It's a cool ride.
That ODK bike is seriously nice. Looking at their website the design is very impressive too - so clean and well-thought out.
I'd prefer an A123 or B456 as they call themselves these days 2,000 cycle battery over the manganese but you can't have everything.
Edit: I see Justin in one of their pictures. So this is the bike he test rode in one of the videos documenting his trip to China.
I'd prefer an A123 or B456 as they call themselves these days 2,000 cycle battery over the manganese but you can't have everything.
Edit: I see Justin in one of their pictures. So this is the bike he test rode in one of the videos documenting his trip to China.
The fingers
10 TW
Two people on a bike in Cali requires 2 seats, 2 sets of handlebars, and 2 sets of functioning pedals to be legal. Putting a child on the back like that might get you arrested for child endangerment. A monkey or a chimpanzee could sit on it, but how many people take their pet primate out for a ride? :lol:
Chalo
100 TW
The fingers said:
Dutch people carry their kids (and each other) around on bikes all the time. But Californians kill cyclists a whole lot more. They also kill a whole lot more children who are in cars. Coincidence? I think not.
Backwardsness manifests itself in many ways; California excels at it. But carrying people on bikes is not backwards. It just takes bikes, and people, that are up to the task.
Wow, so that makes hauling people around on cargo bikes illegal... out in the state with the best weather in the USA..
Nothing surprises me about California. I ran away from there 4 years ago and haven't looked back.
Nothing surprises me about California. I ran away from there 4 years ago and haven't looked back.
lbz5mc12
10 kW
I had a cool rack idea one time. It wasn't for people just cargo. My idea was a kind of universal rack. The rack idea had built in leafs kind of like a dinner table. The leafs could either be pulled out and locked into place for flat and wider stuff or pulled out, folded up and locked into place to work like a basket. This way when it's not in use it doesn't look too bulky or off balance the rear of the bike.
I used to see people riding around with kids in those rear kid seats all the time around here. I never thought they were very safe even when I was little and rode around in one.
I used to see people riding around with kids in those rear kid seats all the time around here. I never thought they were very safe even when I was little and rode around in one.
Just imagining... kind of like a drop-leaf table that can also form a basket...hm, also reminiscent of the VW dropside flatbed, a sort of convertible trucking solution?
This dinner table I'm sitting at is expandable. Making it collapse like a folding basket boggles the mind presently... If you have a pencil maybe you could etch-a-scratch hehe.
aw hell, i have a pencil. of course don't let that stop you if you have a pencil...now, how to fold up the dining room table in three easy pieces... yup this is a brain drain.
One thing for sure if it works it will prob'ly be ill-legal in Cali
Part 2: OK...So I drew the "triangles double diamonds and A frames" which are evident in a bicycle. I came away speechless. The drawings didn't describe it much better.
Upon finding a Weber grill cover in some alley last year, I solved the drop down pickup truck aspect of the 'package rack'. Thanks to whoever threw it out, It cleaned up nice.View attachment 2
Makes a complete skirt around a padded hard floor, removable, no welding, no grief. I use innertubes, cut to make "bungee cord". Works fine for what it is.
harox
This dinner table I'm sitting at is expandable. Making it collapse like a folding basket boggles the mind presently... If you have a pencil maybe you could etch-a-scratch hehe.
aw hell, i have a pencil. of course don't let that stop you if you have a pencil...now, how to fold up the dining room table in three easy pieces... yup this is a brain drain.
One thing for sure if it works it will prob'ly be ill-legal in Cali
Part 2: OK...So I drew the "triangles double diamonds and A frames" which are evident in a bicycle. I came away speechless. The drawings didn't describe it much better.
Upon finding a Weber grill cover in some alley last year, I solved the drop down pickup truck aspect of the 'package rack'. Thanks to whoever threw it out, It cleaned up nice.View attachment 2
Makes a complete skirt around a padded hard floor, removable, no welding, no grief. I use innertubes, cut to make "bungee cord". Works fine for what it is.
harox
