frame help?

Discussion in 'Motorized Bicycle General Discussion' started by racing fan, Mar 7, 2012.

  1. racing fan

    racing fan New Member

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    I have a frame I really want to use but I don't think it will handle what I want to do with it, I need some advise on that aspect. Here is some info on the frame, it's a banana bike frame from the 70's made of steel with 3/4 in tubing used in construction. I was wondering if you guys think it will hold together at 30+ mph? (definitely higher than 30) Another note is the engine will be no less than 7 hp and will probability be 10 hp with a variator for a trans set up. In short it will accelerate hard and also top out at a high speed too. With that kind of power I have doubts about the frame and the forks.


    sorry forgot this part:
    The forks are stock and some 16+ in in length and the taper from about 3/4 of an in. to about 1/2 in and are slightly oval not round. (factory)

    Do you guys think monark forks will hold up to it too?
     
    #1 racing fan, Mar 7, 2012
    Last edited: Mar 7, 2012
  2. mapbike

    mapbike Active Member

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    racing fan

    30-45MPH I wouldn't be that concerned, much above that with the HP you are talking about and I'm concerned....LOL!

    Sounds to me like you're itching to build a death trap.......LOL, a bicycle doesn't require 10+ hp to cruise at a very nice speed and have plenty of power for using a bicycle frame to it's limits, a 6.5hp Honda clone HF engine will push a bike to 50+ mph if set up right and that would be beyond what is safe for most bike frames and the small axles.

    Just giving personal opinions here, not trying to shoot you down in any way, I have three bikes that will hit around 40 mph which is good enough for me on my bikes, I also have a 150cc scooter that will run 60mph which is good enough for a small scooter, I have a 1982 inline 4 cyl. Yamaha Maxim that will go way faster than I will ever want to go, point is that a typical bicycle that will cruise 35-40 mph is what I consider a safe speed as long as all things are good and right, 10+HP engine that will put loads of torque on a bike frame........I'm out, not safe, bike frames are NOT designed for that, I know some may disagree and that's fine, but to me Motorized Bikes should be Fun but also Safe NOT Fun & potentialy Lethal from being to fast & over powered.

    I wish you the very best with what ever you do, but just keep in mind, It's a little underbuilt Bicycle Frame when it comes to putting BIG HP on it.

    Peace, map

    .shft.






     
  3. Allen_Wrench

    Allen_Wrench Resident Mad Scientist

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    The old Schwinn Stingray frames (and even some of the period copy-cats) are pretty solid steel beasts. To be frank, I'd worry less about the frame and more about whatever wheels you use. Especially with the HP you're considering. Mounting such an engine in this kind of frame can be loads of fun too, I've heard. That said, I confess to being curious to see the end result though.
     
  4. haste

    haste New Member

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    Are prewar frames decent? They have horizontal dropouts, looks cool and the steel looks thick
     
  5. culvercityclassic

    culvercityclassic Well-Known Member

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    I have a prewar frame and its a beast, the china girl fits real nice in it also...
     
  6. The_Aleman

    The_Aleman New Member

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    If you doubt pre-war frames, take a look at bairdco's builds, too. Some here seen Baird do over 50 on a prewar.

    The very fact they are around is testament. Honestly, can you see a Huffy Cranbrook being suitable for anything in 60 years? :D
     
  7. racing fan

    racing fan New Member

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    Well it's not prewar unless your talking about desert storm or Iraq.
    I looked more into the frame its a huffy frame and it's weight is considerable for the size. I guess I will beef up the frame and put some other forks on it.
    Thanks to all !!!!!
     

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