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Hi i am taking A level product design, as usual left all my holiday work to the last day. i am going to design a bike rack for the rear of a car, onto which you can mount the bikes onto it at ground level, or close to, and then moves the bikes up out of the way of the lights and numberplate etc. Basically i would like to know what you think would be important in the design of the product, such as security etc and any ideas would be appreciated. thanks very much, chris
 

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Ease of use. 47 levers, 5 pins and 11 springs to mess with are not worth it.

Also look into something that will help with the lift of the load. If it is a single bike rack that is not an issue but multiple bikes could start to get heavy.
 

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Yes and don't forget the acceleration loads. It might be easy to get 100 lbs and a rack and then hit a great big pot hole and put 2 or 3 Gs on the thing. That rack has to be able to withstand the 300 lbs load, both upward and downward. It also has to take some side loading for corners.
 

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ahhh cool thanks soo much would never have thought of that. I think ive set myself quite a hard task but have to live with it now :( Do you think a carrier that locks to the car would be useful, i dont thiink they have been made yet... :)
 

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Just from a ******* engineering background, I think you are going to have several problems. First to make a lift type of carrier would be helpful, but to be strong enough to handle the weight of the bikes, and still have the lifting capacity, its going to be heavy an complex. To raise that much weight with someone small of statue and maybe not in great physical condition, when you put 2 or 3 bikes the weight they might have to be able to physically lift is in the 100 lbs range. I know some moms that could lift that much with no problem, but lots that couldnt.

That means you are going to need to add some sort of way to give some mechanical advantage to lifting the bikes once on the rack. Hydraulics would likely be better, but more expensive and complex. It could be prone to leaks. A pulley system might work, but it would be prone to tangles. I can't think of a system that would be in keeping with KISS.

Now even if you did get all those solved, someone has to be able to practically pick it up and mount it on the car. Not many leave a rack on their cars all the time. Solving all the other problems could lead to a weight of just the rack that would be cumbersome and difficult to get on and off. If you solve all those problems, you have to deal with at a cost that would be competitive with what already exist.

The ******* in me tells me if you solve all the above problems, you are probably at a price point that is going to limit your market size. It might be worth a price premium to a gray haired old fart to not have to lift their bike, but is that a big enough market to really justify the expense to get it to market?

This is not to tell you not to try if you think it will work. History is filled with inventions that people thought were stupid. I remember not too long ago someone came out with a new idea on how to work. I thought it was a dumb idea, who would want one. Well the answer was me and lots of others. I thought the IPAD was the dumbest idea that ever hit the market. But Steve Jobs thought differently and proved everyone wrong again. Who is to say your idea won't do the same thing.
 

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I don't think it would be necessary to move bikes up out of the way of lights since they're relatively see-thru. Plus bikes are relatively lightweight. It'd be easier to lift them one at a time rather than a whole rack full of them.
I'd want a bike rack that's low, easy to load, simple to install, holds the bike by the tires not the frame and allows you to remove the bike nearest the car without needing to take off the outside bike. With no moving parts. But Thule already has one of those. The only problem with it is the price.

I think the simple solution is the better solution. I've made a motorcycle carrier on the front of my truck. No moving parts. It's just a simple tray, and the motorcycle drives it'self up onto it. It's only 11" off of the ground. So it's safer to load. Nothing safe about a 500# motorcycle 3' in the air!
I've seen motorcycle lifts that were electrically driven cable operated that'll hoist your cycle 3' in the air! They cost as much as the motorcycle! Holy cow! I've got $150 in my carrier and it's better!

The only possible advantage I can see with having the bikes up in the air is they would be more likely to survive if you were to get rear ended by another motorist. Now if you were to design a system to lift bikes onto a roof rack that'd be another matter.
 

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Have you considered a wheel-chair/scooter lift? If you check sites such as Independent Living Aids, and other, assistive living web-sites, You may find what you are looking for. There are a wide variety, of lifts, on the market. The units are NOT "cheap", but they are built to take a-LOT of punishment. Most can take up to 500, or 700 pounds (U.S.) and can be strapped on, or clamp down. I know of many people, who use these, and most report very little trouble with these units.

Before you ask, tha answer is: NO, you would not need a doctors permission, or note, to buy such a lift. I have purchased SEVERAL items, from Independent Living Aids, and my purchase is never questioned. All the site cares about is that you PAY for the goods, that you order.

If I may make just ONE suggestion. I suggest that you look at lift models, which can fold up, against the car body, when not in use. This will prevent accidental damage.

I hope this information helps.
 

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I looked at different types of carriers when I bought my recumbent. One was just a bit too short. One I got it long enough but just a flat platform makes it extremely difficult to secure a bicycle. I actually was thinking of wheelchair lifts type systems modified to deal with bikes, but I have my doubts as to whether it can be made cheap enough to be effective for bikes. With wheelchairs its a must and the price is not as important.

Forget mounting anything to the front of a car and it does need to up over the bumper height. If you let a bike ride at 11 inches off the ground, every piece of road debris and gravel is going to be slung up to hit your bike. The lowest part of the bike needs to be bumper high. I wouldn't want anything mounted to the front of any vehicle I owned. If for some reason a strap ever broke, something slipped, or you just forgot to attach something in a hurry, if the bike comes off the front, your bike has almost 0 chance of being repairable at any speed. Not only that after you run over it with your car, you car just might have some expensive damage to fix as well.
 

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I have been using a tray style carrier made by a company called Sport Works for my recumbent. Sport Works switched to only making bike carriers for city buses, trains, etc. Thule took over where Sport Works left off for regular motor vehicles.

I have modified my original Sport Works carrier a bit to where you would not even call a Sport Works any more. Sport works made the carries like mine modular with bolt on options. things like additional trays, etc. I made a set of the holes that would be used for a bolt on addition larger so I could add my own custom made bike carrier module to it.

The module I am talking about is an old half hoop shaped bike carrier used to transport diamond frame bikes. Back when cars actually had steel bumpers the hoop shaped carrier would clamp on to a steel bumper. It was modified to now be used with a receiver hitch. The holes on my original Sport Works that I drilled to be larger are now used to attach the hoop carrier with the pin you would use with a receiver hitch. The tray part of it, or what was the original Sport Works carrier is what attaches to my actual receiver hitch on my vehicle. I also painted the entire thing safety cone orange.

When I only have to carry my recumbent I only use the tray part of it which is never removed from my hitch until I stop riding in the winter. I only attach the hoop module to the tray when I have to carry diamond frame bikes.
 

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Forget mounting anything to the front of a car and it does need to up over the bumper height. If you let a bike ride at 11 inches off the ground, every piece of road debris and gravel is going to be slung up to hit your bike. The lowest part of the bike needs to be bumper high. I wouldn't want anything mounted to the front of any vehicle I owned. If for some reason a strap ever broke, something slipped, or you just forgot to attach something in a hurry, if the bike comes off the front, your bike has almost 0 chance of being repairable at any speed. Not only that after you run over it with your car, you car just might have some expensive damage to fix as well.
In application that isn't necessarily true. Your stuff only needs to be higher than the lowest portion of the vehicle. On my wife's Civic, my 3" floor jack just fits under it so anything higher than that would be protected.
And as far as mounting stuff on the rear verses the front, I've tried mounts on the rear of my camper. Just about lost two bicycles off of the back of a camper. I just happened to see a bike hanging over the side in my mirrors when making a turn. All the motion back there had broken the ladder they were attached to. I'd have lost them somewhere in Kentucky and never even known where to look.
Another time I hd a motorcycle on a platform mounted to the back of another camper. A semi driver flagged me down. Mostly I think because he didn't want to run over a motorcycle in the middle of the road. The straps had worked loose and the cycle was bouncing around on it's suspension "like popcorn in a popper".
In 4 years with the cycle on the front of the truck I can see it's safe. my kayak on the roof sticks out 6' in front of my front bumper. I just about ran it into a quickie mart one day, but I could see it and stopped in time.
I can't really see putting a bicycle on the front of a car because you'd have to drive looking thru a bicycle. I can see over my motorcycle in my truck. The worse debris I ever picked up were a few bugs. It's kind of wierd cleaning bug guts off of the side of a motorcycle.
So from my experience I'd have to say mounting stuff up high and on the rear of a vehicle is the worst option. Although sometimes it's the only option.
 

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Well the lowest point of the vehicle behind the car is usually the bumper. Mud flaps or something like that would protect it from loose stones, but any kind of road debris that could move the flaps could still get to the bike. Higher the car itself is the protection.

Yes you lost two bikes off the back of the camper, but the damage was JUST the bikes. Lose one off the front and you very easily could have damage to the camper. Putting it on the front might help you in some ways, but it also exposes it to damage from debris kicked up by the car in front of you. Here on the freeways a 3 car length space has 4 cars in it. A tread off a semi could do a great deal of damage. Still its your stuff, your choice and no one gave me the divine right to dictate how others should live.

The original poster had a good idea, but its going to really be tough to make it work
 

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That Wizard carrier is not an approach I would take for this reason. IF you had a failure in a the attach point to the rack, with the bike riding in that position gravity will assure you have a bike in pieces. It HAS to fall. If a strap breaks on a more conventional riding rack or flat bed, gravity gives you a chance of keeping the bike in place.
 
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