Livefast Motors 49cc rear mount issues...

Discussion in 'Rack Mounted Engines' started by brujahboy2004, Nov 4, 2012.

  1. brujahboy2004

    brujahboy2004 New Member

    So here I have my first build attempt at a motorized bike. Needless to say, there were quite a few issues that needed resolving to get it to the point of running properly.

    First and foremost, to anyone considering purchasing one of these kits, replace ALL of the nuts and bolts (including the allthread rods for the mount) with higher quality parts (I got mine at Lowe's). These are very poor quality, and you're in for a headache if you don't.
    Second, replace the gearbox's small sprocket with one that he sells (22 tooth) for the #25H chain, as well as the chain itself. The chain included was very weak and ended up losing/destroying the rollers on it, which resulted in skipping and intense popping, causing the integrity of the entire setup to be comprimised.
    The only other issue I have with construction is the support arm, which is an L-shaped threaded rod (allthread). It just doesn't seem to me that it gives enough support to the engine mount to compensate for much vibration. That being the case, for the time being, I'm in the process of fabricating an additional support from another length of rod and a heavy steel, weather-treated L bracket to mount on the opposite side, until I come up with something better.

    Which brings me to my next concern, gear noise.
    Everything is now in working order, to the point of where I can ride it normally without any fear of something else going wrong. However there seems to be ALOT of noise coming from the gearbox. I'm unsure, but it looks to be a box that is custom made specifically for this setup, as I have failed in all attempts to find any kind of details on it. It is a very simple setup with a 3.66:1 (6T to 22T) reduction on the small sprocket, and a 5.33:1 (9T to 48T) reduction on the drive chain. Which would give me (please correct me if I'm wrong; I'm new at this :dunce:) about a 19.5:1 final gear reduction, which seems about right.
    I've lubed both chains well and, initially, it helped immensly. But after about a 15 minute ride, the noisiness noticibly increases till it returns to it's previous state. It really doesn't seem like something's wrong persé, but there sure seems to be more noise coming from the gearbox than it should be normally. The kit even comes with decent quality foam to deaden the sound, but it almost seems like it's quieter with the gearbox cover off than it is on :huh2:.

    Any suggestions or opinions to help get rid of my loud gears would be greatly appreciated. Thanks.:grin5:
    Last edited by a moderator: Dec 18, 2015

  2. Maverick Matt Carty

    Maverick Matt Carty New Member

    rear suspension bicycle

    I have a bicycle with rear suspension that I want to convert to gas powered/assisted. All the conversion kits I have come across are for bicycles without rear suspension, I have however, seen a bicycle with a gas engine mounted on the non-drive side (side opposite of chain), the engine was mounted on the rear fork, next to the tire. I have not been able to find any kits that are like this, any ideas, anyone?
  3. brujahboy2004

    brujahboy2004 New Member

    The most EFFECTIVE way I've seen so far, when it comes to mounting an engine on a bike with full suspension, is to utilize a Jack-Shaft Kit. That way chain tension isn't a problem.
    Otherwise every time the suspension recoils, you're going to have the chain jumping off the sprocket and possibly causing serious damage to the bike components and/or yourself! Wouldn't be good having that happen at speeds approaching 30mph. VERY scary!
    If you have the necessary tools, know-how, and patience, you might be able to fabricate a custom mount that would eliminate tension issues. Just be safe out there. There's more "Raging Cagers" than you can wave a stick at, and most of them won't think twice about running you off the road.
  4. brujahboy2004

    brujahboy2004 New Member

    This might help with some ideas as well. I know, Dax sells a chain drive kit that's compatible with his friction mounting hardware as well. If you're looking specifically for a rear mount setup, friction drive OR chain drive, that you can possibly switch between depending on preference, that might be the way to go.
    Universal friction drive
  5. darwin

    darwin Well-Known Member

    Checkout the axle mount at staton.