I got my son this mini bike from a garage sale with this JF168 engine like others in this board i cant find a repair manual on it he was riding and it just quit running now all it does is backfire into the carb. it was running good i have check all the basic 4 stroke engine stuff air filter,plug,fuel,fuel filter,oil it fires every time you pull it but will not start. If we do happen to get it to start it will run for a few seconds at the most and starts backfiring and acts like it is not getting any gas the guy i got it from said it was sitting for a while so we did the whole new fluid thing oil,fuel filter,dumped old gas added fresh was running good for days then this i have also pulled the bowl off the carb.checking for junk in there and it was clean and fuel flow seemed fine

could this be a shear pin timing issue with the flywheel

also if anybody out there has this engine on anything could you plz post the spark plug number here
not sure if the one we have is the right one looks really long for this small engine but i'm more up on B.&S.
P.S. i found the manual online at the companys web site BUT you need a username and password to get it http://jdshanghai.com/DownloadCenter.asp#

I also emailed the name on the dowload center for some help with maybe getting the manual

thank you for your time and help

Wizard1

Try a new spark plug, I would bet that will take care of it. A fouled spark plug will cause this exact problem, so even if your plug looks good, try a new one.

I would like to know if i have the right spark plug too so if any body has this engine with a spark plug # so i can cross ref. to make sure i got the right one i just replaced the one in the engine with a new one of the same number as the old one but guy i got it from said to was his grandsons and not sure what he did to it like i said this plug looks very long for this small of a engine

thank you again

Wizard1

The correct spark plug for your engine should be an NGK BPR6ES, Champion RN9YC, Autolite 3923, or equivalent.

Thank you very much 30yeartech :)for the info. and help you have giving me i will give it a try a report back

Thank you again

Wizard1

I also needed the book so I ask for a user id and password from the company. This was what they gave me for generic login...
user:jd001
pp:jdsh001

The correct spark plug for your engine should be an NGK BPR6ES, Champion RN9YC, Autolite 3923, or equivalent.

Hi 30 year veteran, I have one of these 5.5 jdong motors and the pull start broke and I want to know where to find parts for this thing. I live in phoenix az, but if you know the specs of that spring thing that makes the rope recoil after pull I would be deeply gratful.
Mike

Hi 30 year veteran, I have one of these 5.5 jdong motors and the pull start broke and I want to know where to find parts for this thing. I live in phoenix az, but if you know the specs of that spring thing that makes the rope recoil after pull I would be deeply gratful.
Mike

Many of the parts on those engines are interchangeable with Honda engine parts, as they are basically clones of the Honda GX engine. If there is a lawn mower dealer in your area that handles Stens parts, they offer many parts that will fit the Clone engines as well.