Engine top end rebuild and an engine stand

Discussion in 'Motorized Bicycle General Discussion' started by Norman, Jan 25, 2008.

  1. Norman

    Norman LORD VADER Moderator
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    Guys I've been working all day today first on building a bicycle engine stand and taking pictures of this then I took the bicycle engine off the bike and tore it down taking pictures and doing some mild performance things that any of you can do I was going to get wild with it but after taking it apart and seeing its a bushed rod on both ends I pussed out as this bicycle engine wouldn't last 5 minutes doing what I had in mind to do. Anyway I'll maybe start tonight on the posts but I'm still puting the engine back in the bike and almost done So when I do start the pictures could you wait until I'm done before you make any comments on this post or if you can't wait and want to ask something pm me instead ok? I'll start as soon as I get the bike going. There's I think over 30 pictures so it will take a while.
    Norman
     
  2. paul

    paul Active Member

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    cool thanks norman. what is a bushed rod? sorry if dumb question but mechanic i am not
     
  3. Norman

    Norman LORD VADER Moderator
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    A bushed rod is a rod that really tired. :confused:rotfl
    I'm yankin your chain again its a rod that instead of needle bearing or roller bearing it has a brass or bronze bushing or some form of brass bronze alloy or other metal. These engines have a sorry what ever metal it is bushing and they seem to wear out on the quick side I'll need to check into a better bushing and there's another project. I'm never going to get it done,.
     
  4. paul

    paul Active Member

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    thanks norman. i am sure that is what i have. its the cheapest kit known to man lol
     
  5. Norman

    Norman LORD VADER Moderator
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    Ater writing the opening on the board I found out my engine has bushing on both ends instead of needle bearing( I kind of figured it did) so no real hot rodding on this but we will go from off the bike to back together on the engine and that is where it will stop cause putting it all back on is only a reverse of takin it all off. I feel naughty when I say thatrotfl

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  6. Norman

    Norman LORD VADER Moderator
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    use vice grips to work arm to help get the cable out of arm same when you go to put it in, saves your fingers.

    Here is whats under the clutch arms cover a ball that alot of you loose and a short rod the ball goes in first then the rod and grease everthing before you assemble it and note the screws the long screw goes on top at the back and doubles as the front chain guard mount.

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  7. Norman

    Norman LORD VADER Moderator
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    master link notice the open end is pointing to the rear when you are looking at the link as chain goes to the front sprocket, Top chain run.

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    this is the easy way to remove the master link clip pliers are pushing the open end off or towards the front pops off the pin in the rear and to come off so easy and you will not loose it this way.

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    see the clip is off the rear pin

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    the little booger that give people fits 10-4! amen and so on.

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  8. Norman

    Norman LORD VADER Moderator
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    I'm going to take the ignitioncoil out and leave it hanging on the bike cause the wiring goes through the frame and I don;t want to fish it through again.next pic. is the coil hanging.

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    no paint under front or rear mount I think this helps to keep the engine from wearing away the paint and that would allow the mounts to come loose then you get to walk or pedal.

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    #8 Norman, Jan 25, 2008
    Last edited: Jan 25, 2008
  9. Norman

    Norman LORD VADER Moderator
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    engine is on the table and I'm going to sort of match the gaskets to the ports opening intake and exhaust using the dremel tool but not now next is a engine stand to make the engine easier to work on.

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  10. Norman

    Norman LORD VADER Moderator
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    using scrap tubing and some strap this is what i'm making what I didn't know is the strap is stainless sreel and I can't gas weld stainless so in the next couple of pic I figure this out and cut a different strap. I did try to arc weld but being out of pratice I burned through the tubing really badly so while cussing I made the changes.

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    TADA! looks like it will work and make life a little easier and its made out of scrap

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    #10 Norman, Jan 25, 2008
    Last edited: Jan 26, 2008
  11. Andyinchville1

    Andyinchville1 Manufacturer/Dealer

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    HI Norm,

    I've been meaning to have a look inside too but been sooo busy with everything.....Hey,
    While you are in there (if you have a degree wheel handy), could you measure when the intake and exhaust ports open and close (degree when each port opens and degree when each port closes)....That'd be REAL handy (i.e. necessary) to more closely calculate header and intake tube lengths for greater performance......I've been doing it by trial and error but scientific would be easier!.....If you need a degree wheel I can give you a link for one but I haven't had luck getting uit to print out properly.
    Thanks!....And good job on all your photo tutorials....They're Grrrrrreat! ;-)
    Andrew

    PS - One mod I have been thinking of was rewinding the coil for more power .....any idea how hard that would be?
     
  12. Norman

    Norman LORD VADER Moderator
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    off with its head and a look in the cylinder a little tapping on the side of the head and cylinder with your hand will free it up do not take a screw driver and pry it apart or a hammer as you will tear something up and thats not the idea of what we are doing if you got a stuck piston in the cylinder use a wooden dowel or hammer handle and tap on the piston while pullin up on the cylinder get inventive but don't tear it up

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  13. Andyinchville1

    Andyinchville1 Manufacturer/Dealer

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    Oh.....I like the engine stand....better and more compact than mine (I took an old diamond frame, removed the fork and sawed off the rear triangle).
    two thumbs up rating!
    Andrew
     
  14. Norman

    Norman LORD VADER Moderator
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    I'm using a .004 thinner head gasket bumps up the compression a little.

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    put shop rags in place before you pull piston completely out of cylinder that way you won't loose anything in the crankcase good idea for rags when working on the rings or piston so stuff doesn't jump into the crankcase when you aren't looking (gremlins you know)

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    #14 Norman, Jan 25, 2008
    Last edited: Jan 26, 2008
  15. Norman

    Norman LORD VADER Moderator
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    How the rings fit on the piston and where the ring locator pin are and how the rings fit etc.

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    Pulling out all of the studs I'm doing this to make it easier to clean the surface where the cylinder base gasket will go the old one is toast when you clean the surface don't gouge the surface. I use a gasket scraper and the dremels wire wheel.

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    #15 Norman, Jan 25, 2008
    Last edited: Jan 25, 2008
  16. Norman

    Norman LORD VADER Moderator
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    another tool to make life a little easier and to protect the piston form being broke and when you put the cylinder back on this is very handy. Would this be a pain to try and describe by words alone. just a piece of wood with a slot for the rod and it steadies the piston like a third hand

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    clean up gasket areas and wash cylinder and head with warm water and dishsoap to degrease it

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    There is no machining on the cylinders top and its a good spot for a head to start leaking from in the next pic I'm lapping the cylinder to clean it up for a better seal at least it makes me feel better. I also did the seal ring on the head no need to get carried away as soon as the rasied ring turns a little dull form the sanding stop and clean it.

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    using 320 wet/dry sand paper glued to glass and soapy water to keep sandpaper from clogging just smooth it up

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    #16 Norman, Jan 25, 2008
    Last edited: Jan 26, 2008
  17. Norman

    Norman LORD VADER Moderator
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    after all lapping gringing etc. clean with warm soap and water.

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    this is one way to make a pattern for a gasket I'm using the studs to hold the paper in place which is computer paper and then I rub my grubby fingers on the paper transfering the grunge on to the paper.

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    explains itself

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    as you can see this is one way to make a pattern and not use a ball peen hammer and risk damaging something

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    #17 Norman, Jan 25, 2008
    Last edited: Jan 26, 2008
  18. Andyinchville1

    Andyinchville1 Manufacturer/Dealer

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    Lol....I like the grunge method!.....Too funny....But oh so effective!.....I'm just curious, how much of a compression boost do you think you got with the thinner gasket?

    FWIW- I have read somewhere (maybe on the pocket bike or moped forum) where some people said you can try running without a head gasket at all provided you lap the surfaces a little to ensure a good mating surface.....I would think that that would cause leaks but then again maybe not?

    Andrew
     
  19. Norman

    Norman LORD VADER Moderator
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    knocking out the base gasket cutting the excess with my punch then on to the scissors

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    some info on what I found on this engine

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    I only smoothed out this area and another out of focus pic. pointing to the transfer ports shoulder.

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  20. Norman

    Norman LORD VADER Moderator
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    got the studs in and the base gasket in place and the little wooden helper inplace I also cleaned the crankcase in the solvent tank blew it out with compressed air and shot some oil on all the bearing surfaces no pic. on that as you can do it with out pic.
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    oiled piston and cylinder indexed the rings so I won't break a ring and the cylinder almost falls in place.

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    I spray a very light coat of cheap aluminum spray paint on the head gasket before I install it. No I didn't paint it there I did it out side.

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