sunofjustice's gearbox idea...continued

Discussion in 'General Questions' started by srdavo, Nov 17, 2007.

  1. srdavo

    srdavo Active Member

    very interesting. seems do-able. using the happytime block....less head, jug, piston & connecting rod.
    Ideally, the crankshaft would be replaced with a plain shaft, but unless you are a machinest...or have one as a close friend...this would be expen$ive.

    Having a manual clutch would open up all kinds of possibilities for donor engines

    Mounting to the bike would be simple....and the whole unit is quite compact.

    does anyone see a down-side or any problems here? I'm all ears!!!

    or should I put this to sleep with the fishes:lol:

    Zomby, excellent thread & info...BTW
    Last edited: Nov 19, 2007

  2. iRide Customs

    iRide Customs Member

    BRILLIANT! Who's going to be the first to attemp this???? I wish I had an old clapped out Happy Time to play with. Looks like a great project!
  3. srdavo

    srdavo Active Member

    haha be careful what you wish for.....sometimes they "clap out" young too!! :lol:
    sorry for the off topic...couldn't resist :rolleyes:
  4. 5-7HEAVEN

    5-7HEAVEN Guest

    :cool: The happy time engine's bulk come into mind, as does the location of its mounting bosses.

    In essence, it'd be like mounting TWO engines in tandem.

    Beside the inexpensive generic jackshafts on the market, there are adjustable "pillow block" supports, pedestal mounts which look like a shaver's safety razor standing upright and others. most need a flat plate welded or secured to the frame as a mounting surface.

    Zomby, how about some links to the gearbox suppliers? I'm looking ,but not finding anything on the 'net.

    Last edited by a moderator: Nov 17, 2007
  5. srdavo

    srdavo Active Member

    as for bulk...I doubt it weighs more or takes up more room than a store-bought gearbox.
    & where/how it will mount seems like a plus. chain alignment to the rear wheel would be perfect.

    you mentioned "inexpensive" jackshafts...pillow blocks, etc.
    I mentioned "recycling". (jackshafts included....and a manual clutch.)

    Now, tell me why this won't work. :cool:
  6. Interesting reuse of parts....I like it!
  7. 5-7HEAVEN

    5-7HEAVEN Guest

    :cool:srdavo, Standing in front of me is my old bike with a very wide cruiser frame. I also have two happy time engines here for measurements/placements. Let me see if i can fit everything into place.

    Even though the engines' top halves aren't banging each other, I can't seem to fit BOTH of them in my frame in tandem.:rolleyes:

    That IS how you guys were thinking about mounting this 4.1:1 "engine-tuned-gearbox", right?

    Even if I removed the engine's top half, this new "gearbox" would be too long for the wide cruiser frame. I tried to turn it in every way possible to facilitate the connection, but no dice. The linked chain would not align with the drive and driven sprockets.

    Please clarify, as I am very interested in finding gear reduction and reverse-direction ideas.

    Hmm, do you realize that by adding another cog into the arrangement that the engine's drive direction will be reversed?

    I cannot appreciate a second clutch in the arrangement. It offers no benefit, therefore might be considered a liability.

    Brian, I'm sorry I might be wrong, because somehow I'm not visualizing what you guys are seeing.

    Last edited by a moderator: Nov 17, 2007
  8. srdavo

    srdavo Active Member

    1 happytime bottom end. (gearbox)
    1 engine of my choosing. maybe a chainsaw...maybe a weedwhacker?

    I am aware of which way engines rotate.

    what if....I use a stretched frame?
    what if...I build a frame around the gearbox & engine of my choosing?
    (would you then tell me there is no Santa Claus?)
    what if....we stop carping on Zomby's thread.

    sorry Zomby
  9. srdavo

    srdavo Active Member

    2nd clutch??
    in my daydream, there is one manual clutch.:p:lol:
  10. 5-7HEAVEN

    5-7HEAVEN Guest

    :cool:That's what I mean, srdavo. In MY daydream, I'm seeing TWO.:confused:

    Will someone kindly explain exactly how this "gearbox" links into the drivetrain ?

  11. sunofjustice

    sunofjustice Guest

    5-7.....I was considering th' same thing th' whole time I while conceptualizing! experiences with a 47cc pocketbike engine is that with a stock CENTRIFIGAL ,3-shoe, clutch.......... hookup is instantanious! Barely off would be able to rev as you like......until you let out th' happy time clutch. About using th' happy time first I thought of just butchering what you need....(transmission)....but, under further observation....leaving th' block Whole (sans cyl./head) allows a perfect platform for th' pocketbike sprocket to rotate, leaving th' block whole adds rigidity to th' gearbox. I have to get another 47cc for mock up, to see if this is really doable......but it looks like theres room to mount th' engine under th' very TOP of a mtb frame....AND still fit th' happy time donor UNDER that in th' stock position. I'm definently concerned about pedal clearance (pedal extensions?) well as WHAT SIZE pocketbike sprocket to use (55t-98t?) Using a strecth beach cruiser bike for more room DID come to mind though.......but I wanted to use th' mtb frames I have now. Got to do some measuring!
  12. 5-7HEAVEN

    5-7HEAVEN Guest

    :cool: Brian, you mean to mount the gearbox UNDER the engine?

    I'm beginning to see your concept.

    Let me do some "Spatial Visualization" and get back to you.(The upside-down puzzle parts need to be connected, just like in an aptitude test.)

  13. Don't own no carps!

    You guys know that Zack has had the same problematic symptoms as all others before. Really!! Go to SEE fo Yo SELF,,,
    We have limitataions that prevent us from from becoming genuine idealists I AM (Pardon) Anothers quote LOOKING FORWARD YO THE RIDE!!!!!!!!!!!!!!!!!!!
  14. 5-7HEAVEN

    5-7HEAVEN Guest

    :cool:Brian, time to start another thread on your pocket bike engine and happy time "gearbox".

  15. 5-7HEAVEN

    5-7HEAVEN Guest

    :cool:In my thread in PARTS&ACCESSORIES, I have a quest seeking a reverse-direction gear-reduction gearbox. Basically, this is what I say there:

    Firstly, this "gearbox" REVERSES engine direction, so cannot be used directly to link the left-side rear sprocket.:shock:

    Secondly, it is the perfect reverse-direction gear-reduction box I have been seeking. Gear selection is easy and readily affordable and available. The box actually reduces gear ratio to 14.35:1.

    HOWEVER, the box must be mounted on the right-side in an UPSIDE-DOWN position. This is so that the 10t output sprocket faces the 7-speed cassette.

    The box's mounting brackets no longer line up with the frame. Mounts must be fabbed, maybe using the box's 4 cylinder head stud bosses.

    Since a pocket bike engine is the only engine that'll fit above the gearbox in the frame, the gear ratios must be able to facilitate an 11,000 rpm range throughout the mulit-speed sprocket range.

    Here's my suggestion:

    6t engine sprocket-21t gearbox input sprocket-10t gearbox output sprocket. This links to 7-speed cassette's 34t-28t-24t-22t-20t-18t-16t sprockets.

    Mph figures at 4,000/8,000/11,000rpm use ALL the gears. They range from 4,000rpm@6.5mph with 34t sprocket, all the way to 11,000rpm@38.1mph with 16t sprocket.

    I will post a more comprehensive gear/rpm spread when I get home tonight.

    Last edited by a moderator: Nov 19, 2007