66/80cc Flying Horse Engine Trouble SPARK PLUG? CDI?

Discussion in 'Electrical' started by BHI420Nati, Jul 21, 2013.

  1. BHI420Nati

    BHI420Nati New Member

    Okay so I got this flying horse engine from china it was running good then started to bog down and then it stopped. If I let the clutch out back tire will lock up. So I took plug out to see if I still had compression. I do. Went to 3 different stores to try and find a spark plug, but all didn't have one and said if I got the wrong one my engine could seize up. I tried the closest one that the 3 stores found, and nothing. What plug do I need? Don't really want another cheap Chinese plug. Also my cdi seems all jacked up. The black part of plug has come undone from wire, which I still rode with it. My gas can leaks. I have a 10 mile ride to work and made it twice in two weeks bc it seems to always break down. So basically I knew it was cheap going in but can I get this thing to ride me to work everyday or should I just go back to a bike.

  2. crassius

    crassius Well-Known Member

    assuming it is the 66cc motor, NGK B6HS will work OK

    the black boot just screws into the wire coming out of the CDI - if it is broken, you can screw on a new one
    BHI420Nati likes this.
  3. BHI420Nati

    BHI420Nati New Member

    thanks hopefully that's all it is
  4. Will122391

    Will122391 New Member

    Try doing a plug test to see if you're getting spark. http://youtu.be/YJFyDYIkElI
    The stock plug wires that come with the CDI fall apart easily. The brass part that attaches to the spark plug often falls out when you take if off the plug along with the small spring behind it, resulting in no circuit/power; so doing a plug test will help you narrow down your problems. In the meantime, order or find some NGK B6HS spark plugs.
  5. HeadSmess

    HeadSmess Well-Known Member

    dont go back to the shop that said it will sieze up with the wrong plug ;) while a recent thread here did prove plugs do affect operating temps to some degree, there is no way the incorrect plug can sieze an engine other than due to mechanical interference. ie, its hitting the piston... or you put something like a 4 in where a 13 is specified... in which case the plug will melt first. once again, mechanical interference :)

    theres always a few things to do first to these dirty contraptions..

    the plug cap will last all of three miles. replace it. either use an eyelet on the end of the wire and (preferably) an ngk bR6hs. note the
    R for resistor. and the terminal needs to be a screw on type, not solid...

    either that or change the cap for a decent one from a standard motorbike. ngk being top choice again. get a resistor version. 5k max.

    plenty of ways to fix that issue. springs, caps, etc.

    the plug itself. the heat number, at first, is irrelevant. stay with ngk 5-7. thread size is a B. projected tip has a P, resistor version has an R, plus a few other letters for variant hex's etc then the heat numbers. followed by a H for the 12mm length of thread. an E has 19mm and wont fit. then S for standard, and other letters for electrode patterns and metals...ie, IX is an iridium tip.

    so B(P,R)5-7HS(or ix etc).

    the number is how hot the plug gets and whether it cleans itself or constantly fouls. cold weather, short rides, low throttle, run a lower number. hot weather, long rides, full throttle, run a higher number...

    you mention your tank leaks. this is usually around the studs. an idea to solder them on, with a washer for extra strength. use acid core solder and a hot iron.

    the symptoms you describe, bogging down and losing power...check under the magneto/clutch cover for oil. sounds like your crank seals are leaking.

    spark is either running or not running. maybe the occasional splutter cough and surge as somethings burning out...

    to check for spark, just hold the plug on the cylinder and spin the engine. it will be apparent if its there or not :)