Disappointed! Bike running slow

Discussion in '2-Stroke Engines' started by painkiller, Jun 6, 2008.

  1. painkiller

    painkiller New Member

    Trying to ride my bike this weekend to save some money on gas and all of a sudden it will hardly break 20 mph. Like it has a rev limiter that it is bouncing off of or something. It is a BGF 80cc and I just got it broke in (barely) was running good the other night and would zip right up to 35mph but was starting to notice that it seemed like it starved out a bit up there. Didn't do that when it was first broke in. Now it is gutless and even seems like it starves out at 20.:cry: Someday's it feels like I can't win for loosin'
    Last edited: Jun 6, 2008

  2. Pablo

    Pablo Motored Bikes Sponsor

    Start with the basics - what does your plug look like?
  3. painkiller

    painkiller New Member

    the plug was a descent med brown, not too rich or too lean. I cleaned it up on a wire wheel just to take the light carbon off it but it made no difference at all. It was in the rain a couple of times this week but I would not think that has affected it. It does run smooth up to that 20 mph mark, but again, it feels like it starts bouncing off a rev limiter or a governor.

    Also, I am still running the original plug, it came with 2 but I can't find the other one at the moment. Does anyone know the AC equivalent # or of some brand interchange?
    Last edited: Jun 6, 2008
  4. Check your exhaust for any carbon buildup. That happened to mine earlier on then decided to do the DAX mod and opened it up. It's a bit louder now but the power is there.

    (Dang. The Dax page with the muffler mod isn't there any more. Basically take off the cap,drill holes in the tube or just cut half of the tube off enough so that the tube doesn't go in that little hole anymore (You'll see what I'm talking about when you take that cap off),install just the cap back on if you cut it off. Then some people added some steel wool to muffle it somewhat. Mine's all open and loud. Remember to put that cap back on. Leaving the cap off is bad. The engine needs back pressure.)
    Last edited by a moderator: Jun 6, 2008
  5. Pablo

    Pablo Motored Bikes Sponsor

    Have you taken your air cleaner off and made sure the throttle slide opens all the way?

    Also Maybe you have a fuel constriction - or your tank is not venting.

    Large has a good suggestion - exhaust blockage will give similar symptoms.
  6. Might want to check the magneto for moisture.....
  7. painkiller

    painkiller New Member

    I blew out the coil and plug wire, test drive fine until 20 mph, took baffle out, test drive = fine until 20 mph. is there a pick up coil or something in the motor that I should blow out?
  8. srdavo

    srdavo Active Member

  9. Yep the cover on the front left hand side, where the wires come out of the engine. Famous for collecting water and shorting magneto out...
  10. Pablo

    Pablo Motored Bikes Sponsor

    NGK B5HS or B6HS and currently I'm running a B7HS and it does just fine.
  11. painkiller

    painkiller New Member

    Thanks for the plug info guys, I might as well pick one up and try it. I blew out the magneto and got just a teensie bit of water, but still cuts out at the same speed. It does sound cool as **** with the baffle out, I was really suprised how loud this is!! Cops would be all over me if I drove it like that!
    Last edited: Jun 7, 2008
  12. I would take a hair dryer or heat gun and completly dry it out. I would also seal it up with silicone on the entry for the wires and the cover gasket. I also run NGK plugs and have in all my metric bikes. I am currently using the B6HS, have changed the plug wire as well as the cap. Big difference....
  13. painkiller

    painkiller New Member

    ok, I installed the NGK B6HS and it made no difference what-so-ever, I will try the hair dryer trick, maybe drain the gas and put new gas in it. I can't imagine the fuel being the problem because it runs too good up to that point. could I being sucking air somewhere? I wish something i have tried would at least have made it worse so that I might have a clue as to what it is.
  14. Need to keep checking things, have you checked the screen in the petcock? Junk in the tank will plug the screen. Take the hose off and see if gas comes out. You can spray carb cleaner around intake while its running to check for air leak, just be careful. being flammable.
  15. painkiller

    painkiller New Member

    Do you see any problems with the magneto components?

    Attached Files:

  16. Well it looks ok except where the wires go into the engine should be sealed with silicone or RTV. The water can get right in there. You might also check the conections from the magneto to the CDI. I see some rust on other things maybe those connections got rusty or are loose. Did you try checking the intake for leaks?

    Oh and by the way I did see another problem, not with the bike but with the camera, the date is wrong....

    Let us know what you find, and Good Luck....
  17. painkiller

    painkiller New Member

    lol. found the problem, it was the cheezy *** bullit connectors on the wiring. I stripped of the plastic covers and soldered them together and then taped them. Runs like a champ again! Thanks so much for everyones help!!!!
  18. COOL..... Time to ride!!!!!!!!!!
  19. Good to hear.:grin:

    Have fun.