CAUTION- PLEASE READ

Discussion in 'GAS POWERED BIKES' started by Beau, Feb 13, 2013.

  1. Beau

    Beau

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    When the "Bikes with motors" section was first built, there were only a few people building these MOTORCYCLES.

    Only two of us were using the 4-stroke Briggs style engines on here, and Cobrafreak once he figured out the little Chinese engines were junk. When the pedals don't propel the bicycle, it's a motorcycle. Not a moped, not a bicycle. These are no longer the basic, light duty Chinese kits that will work on a bicycle for a short period of time. I suggest everyone build a bike with a Chinese kit for practice.

    PLEASE remember that a 3 hp Briggs style engine is a totally different beast than the little Chinese engines. Anything over a 3hp engine is beyond overkill for one of these. Even with a 3hp engine, bicycle tubing is rarely up to the task of handling this.

    They are heavier, have more torque, vibrate more, will go faster, and will need a lot of braking power.

    Adding suspension in the front or rear without knowing what you are doing is very dangerous.

    Using low pressure tires on cheap rims is dangerous. These engines, when properly geared can reach 40-50 mph. Cheap tires can come off the rims.

    Which brings me to wheels. You want good quality rims, with HIGH QUALITY hubs. Spoke gauge is up to you.

    I understand that Briggs style engines are cheaper and easier to come by, but it does not mean the build will be cheaper. In fact, it's going to cost you far more to have a safe, reliable motorcycle.

    Oh and always wear you safety glasses. :)

    Feel free to add to this, or make me look like an a-hole.
     
    AlfredJ and Flying Zombie like this.
  2. Sphinx

    Sphinx

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    Well said. It ain't fun gettin' crippled or dyin'.
     
    Pop.Cycle likes this.
  3. deorman

    deorman

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  4. curtisfox

    curtisfox

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    AMEN to that threr are a lot of builds were they just don't consider Rake and Trail and just think they can tip the front out and think they can go. Then if you add a motor you are looking at a desaster,total lack of control......Curt
     
    dave420 likes this.
  5. JohThomas Sorrels

    JohThomas Sorrels

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    +1000, is there any way for this to be stickied at the top of this forum or something? There are a few builds on here that scare me and it would be nice to make sure others know not to copy them. All we need is a bad crash and home built motor bikes will become illegal.
     
  6. curtisfox

    curtisfox

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    Another amen another thing is that they want to put to big of motors on them and they are just bikes 2 or 3 Hp is a great plenty for a bike. I was brought up in the 50's and all we has were washingmachine motors they were about 5/8 hp and did good at making the old bikes go around town. Most states say 20 mph top so anything faster is eventually going to worent more control and laws. Just this last year they changed so now we have to register them as a moped never used to.........Curt
     
  7. pholTmonx

    pholTmonx

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    I'm a just leave this here..
    natural selection...
     
  8. RollinLow

    RollinLow

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    I agree this needs to be a sticky and people should build a china 2 stroke first to get a feel what 30 feels like in a bike. It doesn't feel like 30 on a motorcycle. Just remember if you put front suspension on a bike and it fails, you are gonna go over the bars and weather it's at 10 mph or 50 it never feels good. I know i can't speak for everyone but I'm sure if anyone has questions people like beau or me would be glad as help answer a question.
     
  9. wheelbender6

    wheelbender6

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    Some people start a motorized bicycle build, wanting to go 40 of 50 mph. They don't understand that they will not be able to make safe emergency stops from those speeds without a brakeset from a high quality downhill mountain bike. Downhill mountain bikes are designed for higher speeds and make a good source for wheels, brakes and forks. I am content to cruise at 25mph. Going faster requires more expensive parts.
     
  10. iven

    iven

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    Good Advice here..
    I seen people put Briggs over 3hp motor on stock WCC's
    & OCC's with the stock wheels, that are junk.

    I gotta get sealed bearing hubs for my motor builds!
     
  11. Beau

    Beau

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    Yes, 20-30 is fast enough.

    My Moped friends hit 50-60 and that is fast for them. A basic moped is built a lot tougher.
     
  12. murraymadman

    murraymadman

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    glad you posted this beau! :wink: i agree folks need to start out with a smaller engine first. the murray motobike i built started with a briggs motor less than 1hp. did great for flat stuff, but it is a far cry from the 4hp that is on it now. the bike i am building now with the 6.5hp briggs will without a doubt be more power that anyone will ever need on a bike. it will be geared for more the torque than top end. lets face it, a 6.5hp geared high? you could reach speeds around 70mph+ if you wanted but that is crazy! heavier rims, tires, tubes, brakes are a must! a couple things i want to throw out is "welds"! i see alot of welding on here that scares the crap out of me! i claim to be no master welder but i feel comfortable with what i do. also, go over the factory "heat" welds on the frames with a welder or braze. don't trust them. and when you can use gussetts, especially where the tubes meet the steer tube. i could go on and on, but just take your time, think it through and ask questions. i would be more than glad to share things i've learned on my projects. :wink:
     
  13. Beau

    Beau

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    I forgot to mention MMM in the first post. He had a Briggs 5s on his, and his build was on here.
     
  14. isaiah3g

    isaiah3g

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    Good idea to get this thread up here.

    Its a dangerous/exciting/ feeling going 60mph flat on bicycle wheels & tires. We did a top speed test and that was the one and only....for that day ;)
    But seriously, if your going for speed, even on a non-par bike, its dangerous. So at least wear an overload of protection.

    Ask me why I say this. I speak for quite a few experiences.
     

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