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How does building your own complete custom road legal car(atleast for the US) work?

  1. Jul 15, 2003 #1


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    Ok, awfully long subject, but its an attention getter.

    Anyhow, my friends and I have been wanting to build small, 1 - 2 seater transport vehicles. I've got some basics on my ideas, hoping to get as light of a vehicle as possible, while meeting modern safety and emmission standards.

    So for starters, I need some information on welding and tubing. I'm wanting to build these vehicles out of tube framed chasis. I assume some type of pipe bending device would be needed, and I'm curious as to how powerfull of a welder I might need.

    I'm not talking about anything more then built by hand, custom suited personal transport vehicles. I planned on using a twin cylinder street bike engine for the prototype, with a drive shaft into a custom rearend.

    Now, for the hard part.

    How do I go about getting such a vehicle road legal? I know with totaled vehicles you apply for a salvage title with DMV. They inspect the car, make sure its road worthy and your good to go.

    But with a completly custom fabricated vehicle, what measures would a person have to take to get something legal?

    I mean, my main design kinda borrows from jets and indy cars, using an almost indestructible cockpit which the driver sits in. Would I have to meet standards, such as airbags?

    I don't think emmisions will be much of a problem, as I plan on using a yamaha engine, some of the most efficient on earth.

    Probably my biggest problems would be getting it approved through modern safety regulations. Any advice???
  2. jcsd
  3. Jul 15, 2003 #2
    Let's start with the most obvious: What are you going to do for insurance? In California, insurance is required to register a personal car. It's probably the same in many states.

    Otherwise, check with those national solar car racing groups for advice. Find out how they were alowed to drive roads in custom cars.
  4. Jul 16, 2003 #3


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    Thats a good idea, I'll have to do that. Thanks for the suggestion.

    About insurance though, seems you can insure anything, so long as your willing to pay the price. And if DMV approves it as a road worthy vehicle, and I can get it to pass the various safety standards, then it seems I should have no more problem getting insured then a person with a street legal dune buggy.

    Plus the fact I only intend on this vehicle having a top speed at maybe 100 mph. And honestly, it wouldn't need to be that fast. I'm more concerned with acceleration.
  5. Jul 17, 2003 #4
    To begin with you will probably need to do a lot of research at your local library to determine the vehicle codes necessary for custom vehicles to be declared road worthy.

    For example: You will need to have at least two rear view mirrors, the headlights will need to be at least 24" up from the ground, the engine must pass emissions (typically), there must be safety restraints (not necessarily air bags, but definitely seat belts), Safety glass for the front windshield, etc...

    You will need to determine the design of the chasis to support the loads encountered. Such as compression, tension, and torque.

    It might be easier to begin with studying about how to build a dune buggy because they will have all the bases covered for building a custom rod and you will not have to worry about street legality issues.
  6. Jul 17, 2003 #5
    I only remember snipits...

    The place; DMV staion in PHX, AZ (I think)
    The date; 1970ish
    The official word at that time;
    "You have to have lights, brakes (including park brake), wipers,..."

    I forget what else, but it wasn't very much really. I would check with your local DMV.
  7. Jul 17, 2003 #6


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    Although there will be a number of things required for getting a vehicle like this road worthy, I wouldn't expect emissions to be one of them. On a one-off situation they cannot do much about it unless you live in California. There MAY be other states that have similar laws but I am not aware of them. I highly doubt windshields are an issue since motorcyles are not required to have them. One other thing to consider is to check into getting a VIN from a vehicle in the 30's or 40's. There are alot of street-rods out there that don't even look close to what is on the title and don't have a single original part on them. I would say the first place to stop is the DMV.
  8. Jul 18, 2003 #7


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    I've got a lil exp in racing and custom cars. Well, karts to be specific, but I believe we've got a pretty solid design.

    As far as emmisions go, I think a single cylinder 4 stroke 250 or even 500 cc engine would blow any car out the water in emmisions test.

    Thanks for all the suggestions and information, hopefully I'll come up with something cool. I'm working on a 3d model right now, perhaps I'll post some pics of it in the near future.
  9. Jul 19, 2003 #8
    Suggestions, Shawn your going to want to tig weld that frame for maximum strength and penetration. Although a good DC arc welder would do the trick also. You need to aquire a VIN number and it needs to be stamped on the frame. Go to your DMV and ask for one. Then you will need a MSO for the motor and transmission, and need to create one for the frame (manufacturers statement of origin). Since you are the manufacturer of the frame you will have to produce one. Then take all three mso's into the dmv to get a title. Then get worried about the saftey regulations for making it road worthy. I am unsure how financialy secure you are, but crash testing and other testing to prove it's reliability may be out of the question, You may get pulled over just because a police officer doesn't know what it is even so you have mirrors and turn signals etc.
  10. Jun 13, 2004 #9
    road legal transport

    I was wondering if you have found any information that helps with the legality of building this type of transport. I live in Australia and have an off raod buggy and was wonder what it would take to get it road legal? Any information would be excellant
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