Is the roller bearing supposed to move around????????

Discussion in '2-Stroke Engines' started by hot70cc, Sep 25, 2007.

  1. hot70cc

    hot70cc Guest

    There seems to be alot of movement with the bearing, it the same size , I'm just wondering if it is supposed to be like that or i need a bigger bearing to make it tight
     

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  2. hot70cc

    hot70cc Guest

    guess i brought up a good question that no one knows . anyone? anyone? know?
     
  3. Butch

    Butch Guest

    It is supposed to move back and forth. The newer 70cc DAX motors with the upper roller bearing are the same way.
     
  4. azbill

    azbill Active Member

    that looks wrong
    side to side is good but it shouldn't be able to twist
     
  5. hot70cc

    hot70cc Guest

    I do have the new 70cc motor, My other needle bearing broke apart. So now i'm getting 2 different opinions. Which is it ???????? Yes Or No lollololl. Butch? or azkronic?
     
  6. Butch

    Butch Guest

    In my opinion if there's little or no up and down movement when the bearing is centered on he upper connecting rod you should be good to go.
     
  7. hot70cc

    hot70cc Guest

    i have the solution to the bearing fix, i took it to a small engine repair place and me and him worked to solve the bearing issue from moving outta place. as you can see in the pic we placed 2 washers machined within thousands on each side of the bearing so the bearing will not move out of place and stay in between the connecting rod center. I have the engine all back together and it runs smoooth and seem to hold up really well. He also honed( spell chec) the cylinder out a couple thousands. made alittle more power. new piston and rings.
     

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  8. ibeenjammin

    ibeenjammin Guest

    Please explain how he honed the cylinder to gain more power....I am very intrigued.
     
  9. hot70cc

    hot70cc Guest

    Bigger cyclinder equals more power. took about 1 1/2 hours to do with a hone tool. My gashes where that deep we had no choice to keep honeing till the cylinder was smooth enouph for the new piston and rings. hope that intrigued you more
     
  10. ibeenjammin

    ibeenjammin Guest

    I can understand new rings, but why a new piston head, is it cracked? So if their are scratches in the cylinder, should it be honed? I know that I have some scratches in my cylinder, but I thought that this is normal. I have also noticed a decrease in power, mainly climbing hills. I don't know if you can answer this for me or not, but is the cylinder supposed to be scratch free? I would think that is impossible. Hmmm... Thanks for the help. oh yeah, maybe you already answered this, but where did you get the needle bearing at and how much did it cost? How much did it cost to hone your cylinder out?
     
    Last edited by a moderator: Sep 30, 2007
  11. hot70cc

    hot70cc Guest

    ok, for 1 your never gonna have a perfect cylinder. The littlest piece of dirt can scratch you cylinder. The reason why i had to get mine honed out so much is that my cylinder was almost beyond repair due to the needle bearing braking apart into pieces. As you can see at the beginning of my Post at the top, the bearing was destroyed, all that metal went in between my piston and piston rings and smacked the head. The best way to test your cylinder is to run your fingernail along the scratches , and if your nail catches on it, its best to get it honed, if not your gonna loose power, compression, and get what they call blow bye. I got it from my local STIHL, small engine repair place. Only $9.95.
     
  12. hot70cc

    hot70cc Guest

    Pics of piston, and needle bearings

    Ok my old needle bearing is in a different forum here is a pic of them, and my piston, As you can see on the top of the piston was really hit hard around the edges. And the side of the piston has a 3/16 inch gash takin out of it from the pieces going along side of it. That is located right above the wrist pin hole. So as you can imagine what my cylinder looked like. Just to warn you all check your piston and bearings, the first unusual sound your hear check it, cause 9 outta 10 thats what it is.
     

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  13. ibeenjammin

    ibeenjammin Guest

    :shock: Holy Shnikey's!!!!! (I think I can say that here ;) ) I fully understand now. Yes, you definately needed to replace your piston. Are you able to use the same size piston? Where did you get the needle bearing? Did you buy it off RC Junky? I was thinking of picking one up off him if he still has some. Thanks for the torough update. It is much appreciated! :cool::cool::cool:
     
  14. Scottm

    Scottm Guest

    I was the 1 out of 10 with rings catching the port. A little OT, sorry. http://www.motoredbikes.com/showthread.php?t=6842

    That's a shame the bearing came apart. Hopefully the washers you had made will keep the pieces contained in the event of another failure. I'm no mechanic (yet), but will the washers prevent the bearings from getting the proper amount of lube?

    I asked Duane at Dax if he wanted the cylinder back for refurbishing and he said it couldn't be honed due to the nickle plating. Are you finding any issuses regarding that. I wouldn't mind having it honed out a bit if it would still work. Mycylinder was gouged pretty bad. See pic of my piston.
     

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  15. hot70cc

    hot70cc Guest

    It can be done, mine was pretty bad, but it all depends who you take it to. It takes alot of pumping and drilling. More and likely with the looks of your piston , your cylinder is prolly gouged pretty bad. Thats worse than mine. As long as you or someone don't remove to much of the cylinder to make the rings not be snug in there you should be ok. The guy that did mine said i almost lost my cylinder due to alot of honeing, cause it made the walls thinner, almost to the block, or caseing whatever you wanna call it lol.
     
  16. hot70cc

    hot70cc Guest

    the bearings are not affected bye the washers due to the holes in the connecting rod, still recieve the same amount of lube
     
  17. minibiker

    minibiker Guest

    hot70cc and scottm where did u get your pistons at i had a rock stuck in my engine long story short i did a lot of spacing and modifieing to make a kings piston work and they are totally different (ports and wrist pin height any info would help
     
  18. Egor

    Egor Guest

    I had the big end rollers come apart and do the same thing. I got a new cylinder kit from kings, it comes with a new piston and pin. You can't hone these cylinders the parkerizing is too thin for that. If you get it too thin it will flake off and start tearing things up. If you want to use the best wrist pin bearing check out the bearing for a Stihl chainsaw, I think it is a 035 uses a 10mm pin. Have fun, Dave
    PS: Make sure all the bits are out of the crankcase,the most tiny piece will do you in.
     
    Last edited by a moderator: Oct 2, 2007
  19. Scottm

    Scottm Guest

    PS: Make sure all the bits are out of the crankcase,the most tiny piece will do you in.[/QUOTE]

    I used the premix fuel and filled the lower unit up shook it around and dumped out 3 time to get all the garbage out of it.

    I bought my motor from www.thatsdax.com so that's where I got my parts from. Cylinder, rings and piston. For some reason it took about 2 weeks for parts to arrive. The longest two weeks ever.:-/ But the bike is better than ever.:grin:
    Good luck
     
  20. hot70cc

    hot70cc Guest

    Ok here we go, you can get pistons from dax, and yes it takes a long time to get stuff if you don't ask him to ship next day air. Even though i paid for next day air i still had to wait 4 days. DOn't know why. HMMMM?? He is still a great guy to deal with, answers you questions almost immediatly Anyway My rod bearings are From a STIHL dealer that specializes in chain saw small engine repair, and the roller/needle bearings are industrial strength. IT still only cost me $10 for the bearings. He said even though the cylinder is nicklized it still should be ok. He deals with those issues all the time. So anyone can take whoevers advise they want to. I'm just listening to him cause hes been in the business for 10 years . Iv'e learmed a great deal about these engines in a few short months, about the assembly parts and mechanical issues that need to be done for a strong and dependable engine. The way my engine is now should last 6,000 miles and more. Bye the way Try CEN-PE-CO lubricant 2 cycle. Works wonders, just follow the chart it works . Only $4.00 a quart.
     
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