OIL PUMP PROBLEMS 139QMB?

[playinrent]

Hi everyone, new to the forum and have a question about a 50cc I just bought. The guy had done some mods ...big bore kit and 44 mm sroker crank. The bike has a slight knocking. not loud, you cant evem hear it when its revved. I was going to pull the jug and maybe replace the big bore that was on it. Anyway the guy said he was told it needed an oil pump. What is the easiest way to check if an oil pump is working without pulling the crankcase and stator? I started it and pulled the dipstick out and oil would splash out of the hole onto the exhaust. this leads me to believe that the oil is circulating in the motor.ANY THOUGHTS


Also the tail running light does not work, but will come on when the brake lever is pulled. I checked the buld, its good. Ground seems to be good, one of the turn signals is out, could that have caused it?


Next to the battery there was a small circuit board with a bunch of push buttons and a thin rd and black wire, do you know what this is?


The knock seems to be coming from the top end. Does anyone have any experience with the 44mm stroker crank and a big bore kit? Are their clearance issues?


The moped is a basic Chinese 139 qmb I guess the body style would be like a VIP with a tank front, the flat front with a headlight in the middle.


THANKS FOR YOUR RESPONSES, HAPPY TO BE HERE

[Rebel]

Yeah don't know of any way to check the oil pump without pulling it apart.

Historically putting a large BBK in the 50cc motor makes the crank bearing wear out sooner.

Can you post a pic of that electronic board your battery is connected to.

[velociraptor]

Run pre mix pump should put out a set number of drips per time period I have to look in my lil manual lol

[velociraptor]

With a bbk BTW you need a better oil pump esp that big or just run pre mix fuel the "knocking" could be a bad wrist pin bearing piston slap from a worn or cracked skirt ect

[Rebel]

I think he posted about a 139qmb, that would be a four stroke and not need the oil/fuel mix pump.

[velociraptor]

Ah lol god I miss just Honda ecr motors all these number codes drive me batty