Engine Trouble Bike ran rough, now won't run at all

Discussion in '2-Stroke Engines' started by artmaker, May 28, 2012.

  1. artmaker

    artmaker Member

    First time needing engine work. I'm no mechanic.

    So already had my bike out this year. Ran fine. (It's a few years old.)
    Today I topped off the gas, just a little, didn't need much but it was almost empty. rode it around town and planned to ride to the local events for memorial day. But... it was running bad. Mostly when I slowed down, then went to give it fuel it wanted to die. Had no power. I had to peddle to help it up to speed. NEVER Had to do that before. Once I got it moving it seemed fine. When I got it home I left it running and in neutral gunned it several times thinking maybe I had gunk collecting in the exhaust? It would fire up just fine. So ok, I shut it off. About a half hour later went to go for a short ride again only now it simply will not stay running at all. While I'm peddling the engine is running but as soon as I give it gas it dies. If I put it in neutral it does. And saying it's running while I'm peddling, isn't that like saying a car engine is on while the starter is turning it over? Not quite the same.

    I did try to find this problem but not really sure what it is or what to search for. You folks are much more likely to tell me what to try. So sorry if this is a common thing. Just point me to the thread/S if it is.

    Fuel line seems fine. I did check the obvious things like the fuel valves and such. (I've done that before.) I did look at the wire for the cut off and it too looks fine. button not sticking or anything like that.

    now the plug, might be the problem???? I don't remember the spark plug cap being loose. But it wiggles around on there. Shouldn't that snap on tight?
    I read in the first post here to turn the peddle and look for spark.
    Folks, there is no way.
    I don't have a bike stand. And turning a peddle without my leg and weight doing it is darn near impossible. I did attempt to peddle and with my hand reach down and giggle that cap but it didn't seem to make any difference.

    Would that suddenly and for no apparent reason just get loose? Other things can wiggle loose so perhaps? Should I order a new spark plug wire?
    And how does that install? It seems to wire directly into a black box attached to the bike.

    Anything else more engine internal I should be worried about? It's got (guessing since my odometer also broke) over 1600 miles on it since I bought it almost new.

    This is it when I first bought it. http://artmakersworlds.com/testing/Bike/Bike1REPLACED.jpg

    Open to suggestions.

  2. Al.Fisherman

    Al.Fisherman Active Member

    If your plug cap wiggles, I bet you have a stock spark plug. Buy a NGK and a new wire/cap. The wire is held into the CDI with a screw. Unscrew as you would normally, and their might be a little epoxy/glue holding it in, so you might have to dig it out, which is doable. If that doesn't help, read this....
  3. artmaker

    artmaker Member

    Ok, dumb question time.

    What is NKG? And wire held into the CDI????

    By stock plug do you mean bought at a car parts store? Yes it was. It's been working fine for about a year. Is there a better option?

    Also the wire cap on your site doesn't quite look the same as mine.
    Perhaps pictures would help? Let me know. I can pull it out of the garage and get some pictures of the plug and cap.

  4. artmaker

    artmaker Member


    Took it to my mechanic (car) He looked at the plug and wire, cleaned it. Said it's making connection. And that's as much as he knows about this.
    Tried to get it to run on the way back home and the engine will stay running, though I have no power. So I tend to think it's not the plug. No spark wouldn't it just quit?

    So... what would cause this loss of power? Go read my first post. It was running, sputtering and losing power only when I slowed and tried to go again. Then about a half hour later, that was it. Couldn't get it to power the bike at all. Engine on and running, just nothing when I give it gas.

    It's got to be something else.
  5. Al.Fisherman

    Al.Fisherman Active Member

    Last edited: May 30, 2012
  6. artmaker

    artmaker Member

    I did read that. Basically it could be anything. I'm trying to find someone who has had a similar issue who can at least point me in a starting point.

    Gees, if you take your car to the mechanic do they start re wiring it, then pull the head gaskets, they declog the exhaust, then clean the gas tank? Come on. someone must have a clue what is actually wrong.

    (LOVE your political correctness sig file there. lol.)
  7. artmaker

    artmaker Member

    Say, on another forum, someone else suggested head gasket. I think that might be it.
    Also the piston seems real coated in gunk.

    here... before I do anything else I need some input on what and how. Should I attempt to clean anything????

    have a look. Pictures always help.
  8. artmaker

    artmaker Member


    It's at my mechanic. RINGS!!!!! They are shot.
    So... I need to order rings.

    off to find a good parts site.
  9. BigBlue

    BigBlue Active Member


    glad that you took it to a mechanic. Good mechanics test components to try and eliminate possible problems - not throw money at buying parts to see if that solves the problem. It's a process of elimination. Either you do it yourself or pay someone to do it. Hope new rings solves the problem.

    From my experience, AI.fisherman is very good at determining solutions to members problems and is a great resource. He gave you some good advice and you read it, but didn't state that you went through testing individual components. I guess that's why you took it to a mechanic.

    To save yourself some problems in the future, take some time to learn the basics of engine repair. It's cheaper in the long run.

    On a positive note, you've gotten a lot of bang for your buck without any problems - so feel yourself lucky! Others haven't been so lucky. Some haven't taken the advice from AI.fisherman and ended up throwing their bikes in the trash after becoming frustrated.

    Good Luck,

    AKA: BigBlue
  10. artmaker

    artmaker Member

    Al may be very good. But I'm not. And don't really have time to sit down and in one day try to dismantle and learn an entire motor. It's why I bought my bike with motor already on. One part at a time though I will learn. Already managed to change the exhaust gasket without any problems. It's a start.

    Sending me to a page that starts with check pretty much everything one part at a time is exactly why I came here to avoid! And even with my limited experience with fixing motors I've had cars long enough. I know if it's getting fire and turning it's NOT electrical. Safe to rule that one out. safe to rule out exhaust clogs since before it stopped idoling I was able to rev it up high without any backfires or sputters. So not that. Loss of compression though, that's internal and out of my level of knowledge.
    (Until today.)

    And... my mechanic did NOT have to trouble shoot. It's because he's good!
    I simply explained what it was doing, and literally before I could finish the sentence, and without hearing or seeing the bike, he said the rings are shot. Sure enough. One was in pieces.

    And now, I've seen the whole top section of this thing dismantled and was able to pick the brains of the people who know. Now I know. Should this ever come up again (and we all know it will) I'll know what to look at.

    Haven't yet had the carb apart, let alone clutch or any of that. So at some point I'll be back. Hoping someone doesn't send me a list of every part ever invented and tells me to read it all.

    By the way, I was reading somewhere the explanation of how to put new rings on. And by Al. So yes, he does know his stuff. But he never once suggested look up fixing the rings. Or mentioned symptoms of bad rings. That would have helped. It's ok though. some of the best mechanics aren't necessarily good at diagnostics. Kinda like the younger mechanic over there. Did fine at removing the part. Once the older guy said rings and he knew what to do.

    make any sense?
  11. BigBlue

    BigBlue Active Member


    Glad it worked out for you. As long as your happy, that's all that matters!

    Good luck,

    AKA: BigBlue
  12. Al.Fisherman

    Al.Fisherman Active Member

    Here are answers to both of your questions. Your mechanic got lucky, personally I wouldn't pull the cylinder before I did a compression test. There are a number of things that can cause problems with these engines, and that is why I took the time to write up this document. It could of been easily a blown crankshaft seal.

    Attached Files:

    Last edited: May 31, 2012
  13. motorpsycho

    motorpsycho Active Member

    it could also have been something as simple as a plugged vent in the gas cap.
    he got lucky guessing that it was the rings.
  14. Lunardog

    Lunardog Member

    I'm inclined to agree with Al and Motorpsycho. One issue with an engine can be the result of ten different causes. A clogged fuel filter is a simple check where removing a jug and inspecting rings can sometimes cause other issues during inspection. Common sense dictates, assess the problem....list possible causes....seek out the experts....start at the simplest point and work up from there.
  15. artmaker

    artmaker Member

    Time will tell if he "got lucky." I doubt that. But will hold anything further until after the bike is running. I'll post a follow up then.
  16. cosworth

    cosworth Member

    You have provided a wealth of information both for the new and experienced rider. I could use a little help myself. My bike,with only 50 miles on it is starting to run rough and down on power at the low end. Picks up nicely at 1/2 to full throttle. I'm still running 20:1 gas mixture and changed to plug to an NGK one step hotter. I've checked for air leaks and found none. Don't want to spend the money on the Jaguar CDI set up so do you have any recommendations to cure the jerky and rough low speed power?
  17. artmaker

    artmaker Member

    I should probably post a follow up to this.

    Yes my rings were bad. One was almost completely gone when we took it out. SO I don't feel bad about replacing those.

    But the bike still ran horribly.
    So I tried another mechanic. This one was actually the son of the guy who owned the shop and he had a real interest in small engines.
    Got it running like a top. Mentioned changing the gas but I didn't pay much attention.

    Got home, ran great. Until I topped of the tank and suddenly here we go again.

    This gas was fresh (prior at least to changing the rings.) Brand new gas. Brand new oil.
    But.... apparently it was simply bad gas. I took another can, got new gas and oil, drained the old and replaced it.
    bike is fine. Ran many miles last summer with no issues what so ever.

    And that bad gas? I use it on our fire pit outside now.
    It BOILS!!!!! God I wish I knew where my husband got that. He doesn't remember. But gas should not sizzle when you dump some on a raging fire. All this started when I got that gas.

    Though the rings were bad. Good thing we changed those regardless.

    Anyway mine is fixed. Hope you get help with yours.
  18. Fabian

    Fabian Well-Known Member

    I have read this thread with great interest, but it's best if i just keep my schnabel halten.