Need help

Discussion in 'General Questions' started by JD 4020, Jul 21, 2016.

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  1. JD 4020

    JD 4020 Guest

    Hi everyone I just received a EL cheapo roadmaster mountain bike with three front speeds and 7 rear speeds. I would like to mount a 3hp flat head Briggs engine on her above the rear wheel (won't fit in the frame) I'm going from a #40 chain 10 tooth centrifugal clutch to a 30 tooth on a jackshaft from there I want to have a 14 tooth #415 sprocket to my hub adapter one from MM. A few questions is the wheel sturdy enough for the torque (14g)? And you might ask how the engine will be mounted? well I'm making a bracket that will weld onto the steel frame. Thank you anything will belp.

  2. Steve Best

    Steve Best Well-Known Member

    Man, I am using 410 (BMX single speed) 1/8" chain on everything now.
    Love it. Light, quiet, cheap, strong.
    GIANT is my favourite brand. Just put a SRAM on tonight and hated it. Clip sideplate didn't fit. Chain wore significantly in the first 10 minutes of use and again in the next 30 min. The GIANT brand chain was better quality and cheaper. By my figures I am making 3hp or more on my 66cc single speed, although less torque. I've burnt 2 wheels out in the last 6 months of riding, mainly from dirt, low lube and speed. Get the bike shop's opinion and get them to lube up the bearings.

  3. Frankfort MB's

    Frankfort MB's Well-Known Member

    Loosen up the hub a little, just enough to get a finger in, then put as much High Temp suspension grease as you can in there....
    It's the right consistency for these bikes too roll smooth but not too burn up the grease from heat
    (I've had experiences with regular wheel lube getting too hot and getting sticky so the hub wouldn't roll)

    That will severely prolong the life of your wheel

    (A high quality wheel and parts would help too, but I can only afford so much just like everyone else)
    Steve Best likes this.