How to get piston back into cylinder?

Discussion in '2-Stroke Engines' started by dancycle, Dec 9, 2007.

  1. dancycle

    dancycle Guest

    Hey, I had to take the cylinder casing off to replace a gasket and now i'm trying to figure out how to get the pison back into it. I've tried squeezing and messing with the rings, but I just haven't been able to get them to fit back inside the cylinder. I looked for previous posts but couldn't find anything relevant. Any help would be much appreciated.



  2. azbill

    azbill Active Member

    it sounds like the locating pins are what were giving you the problem...

    each ring slot has a little pin
    the opening in the ring fits over the locating pin
    as you are pushing cylinder down, compress bottom ring, then top
  3. kenspice

    kenspice Guest

    If you can't compress the rings enough to get them into the cylinder you can take it to any small eng repair. They should have a ring compressor that will fit your small piston rings.
  4. dancycle

    dancycle Guest

    Ok, thanks guys. I have one other question. I was just wondering, is it possible to run safely with only one piston ring?
  5. ibdennyak

    ibdennyak Guest

    install rings

    I've been known to use a hose clamp with grease to install rings upon occasion.

  6. Abeagle

    Abeagle Guest

    Running only one piston ring can cause compression loss and the piston riding incorrectly in the cylinder bore, not to mention possible cylinder and piston galling. I would not recommend it.
  7. azbill

    azbill Active Member

    these rings are very easy to do with just fingers
    I have done it at least half a dozen times with both dax and livefast heads
    the hard part is not getting any permatex copper on your hand while doing it :D :lol:
    (put the gasketmaker on the block and won't be as messy !)
    Last edited: Dec 9, 2007
  8. dancycle

    dancycle Guest

    thanks for the help guys :cool:
  9. kevbo

    kevbo Guest

    I've not yet had to pull the jug on my HT yet. On BMW motorcyles, I've pulled the jug off just far enough to take the wrist pin out of the piston, leaving the rings seated in jug. Is this possible with the HT?
  10. Egor

    Egor Guest

    Answer YES. A lot of the racing pistons I have put in my bikes over the years only have one piston ring. I have a happy engine now with only one ring on the piston, I have a lot of miles on it, It actually is easier to start, it does not fight compression. the rings only keep compression and combustion gases on top to do work. Oil keeps things from sticking. Have fun, Dave
  11. dancycle

    dancycle Guest

    yeah, I figured out that the piston has the little pins a bit too late. I was trying so hard to compress the top ring that it snapped on the pin. :( So now I have to get another set, but at least I know how to do it now. Again, my impatience biting me :(
  12. kenspice

    kenspice Guest

    Definitely get a new set of rings! Installing one ring is asking for future trouble and expense. You should be able to install them with your fingers. If not, a hose clamp and a drop of oil as suggested will do the trick. Putting one ring on your piston is kind of like putting a small wheel on the front of your bike so you will always be going down hill.....
  13. Egor

    Egor Guest

    Just for a giggle give it a try. Move the ring to the top slot put it together and try it out, like I said I have one that way for over a year. The small pin is gone for that ring land so the ring would just move over and get in the port. So this is the fix for now, I have a new barrel and piston to replace it but why, it runs good, I leave it alone. You could do this till the new one arrives. Let us know how it runs. 45 years as a motorcycle mechanic you learn tricks. Have fun Dave
  14. kenspice

    kenspice Guest

    Could be an expensive giggle. Unless its an emergency, try to put your engine back together with all its parts. ABeagle summed up the reasons why. 51 years as a mechanic and still find it best follow the book.:smile:
    Last edited by a moderator: Dec 11, 2007
  15. locoWelder

    locoWelder Guest

  16. dancycle

    dancycle Guest

    So I take it that there are different opinions on the subject. I'm not sure what to do though. Like I said, one ring is still intact, but the other broke in one spot. I'm just not sure I can find another ring to fit my piston. Is it possible to use somekind of "steel-bonding" product to mend the broken ring, or is that just asking for trouble?
  17. azbill

    azbill Active Member

    who did you buy your kit from?
    they may sell rings
    or, somebody here might be able to tell you where else to get them
  18. dancycle

    dancycle Guest

    I bought my kit from a guy on ebay. I emailed him asking if I could buy the parts, but haven't gotten a reply yet. The ones I saw on looked like they might work. It is called "Precision High performance Piston Ring Set 70/80cc." The fact that it says 70/80cc makes me think they are a generic/standard size, and my engine appears to be the standard chinese engine.
  19. Alaskavan

    Alaskavan Guest

    Last edited by a moderator: Dec 11, 2007
  20. Egor

    Egor Guest

    Kings and Dax have rings. Kings has a barrel kit, with a piston fitted.

    Attached Files:

    Last edited by a moderator: Dec 11, 2007