I Really Dont Want 2 Split The Case In 2!!!

Discussion in '2-Stroke Engines' started by Cyclelogic83, Jun 20, 2011.

  1. Cyclelogic83

    Cyclelogic83 New Member

    Fellow M'bikers of the world, I have a dilema.
    Let me run it by you, to get some opinions.
    I have 2 ht engines.
    Engine No.1 (F80b) is only a few months old, but recently began making fairly loud geartrain noises on the clutch side, & upon investigation I found that the crankshaft has about 1.5-2mm side 2 side play, & there is slight gas\oil mixture on & around the magneto, not a whole lot, but enough to see its there. So from my homework here on MBc, I assume the bearings are shot, & as far as i can tell I need to split the case in 2, to replace the bearings.

    Engine No.2 (a $10 unknown origin special) needs a new top end, but the bottom end seems solid, although it looks to be a few millenia old!!

    Is it ok to take the top end off engine No.1 & put it on engine No.2???
    Should engine No.2 be considered a ticking time bomb because of it apparent age???
    Or should I stop being such a cheapskate and rebuild No.1??
    I will be ordering a new RSE, either 49cc hp stge 2 or a 66cc hp stge 1 in the coming weeks for my cruiser build, but I would like to keep my old thrasher alive for the occaisional dirt track thrash!!!
    Any sugestions/advice would be greatly appreciated as I'm travelling by pedal-power at the mo!!!
    Also any recommendations on the RSE 49/66 will be taken on board.
    Thanks, Chris.......

  2. HeadSmess

    HeadSmess Well-Known Member


    ha ha ha ha ha ha ha :jester: get a new one. not like they cost the earth. fleabay...160...hmmmm
  3. Mountainman

    Mountainman Active Member

    if the parts are the same
    sounds like a fun project just for the heck of it
    sounds as if THINGS are worn and torn
    kind of like
    Rode Hard and Put Away Wet if you know what I mean

    if you know what I mean
    I perfer a tight machine
    don't want one burnt out that burns too much oil
    better young and fast
    with a very hot coil
    Last edited: Jun 20, 2011
  4. BoltsMissing

    BoltsMissing Active Member

    Suggestion: Build one good engine from the 2, from scratch.
    But as far as bearings and seals go, replace with quality.
    Use new gaskets all round. Head gasket and cylinder-to-case gasket might be best to get new from the local aussie distributors cos the thickness sort of gotta be right, if you understand 2-strokes.
    You'll gain experience at least and probably work out of your own mods along the way.

    If it all fails, yeah, buy a new one, at least you'll know the engine and be able to offer advice on here from your own expriences!

    The problem with re-building a old or broken engine is getting it cleaned to start with. Scrubbing old gaskets, washing up afterwards. These are added hidden costs, and time. Versus the cost of a new engine, or a full kit cos the parts break down eventually, so ya use what works and a full new kit is stored as spares.
  5. q999

    q999 Member

    new engine if you can swing the cash..

    for under 100 a new motor that's not even a tank of gas for a suv,
    also note that the price will probably drop in the winter months.
    I noticed that http://stores.ebay.com/BoyGoFast on ebay was temp sold out ,he was the cheepest I know of..
    he does sell jugs,pistons ,ect ..
    good luck....