JR50 Engine Problems

[Dobey58504]

Hi Everyone, I'm pretty new to the minis. My son has a 2000 JR50 and the motor turns over but the piston doesn't move. Is there something behind the case cover that might have broken? I got this for him to start learning on and thought that he could move up to a Polini or KTM 50. I would appreciate any ideas, someone here told me that the crank is shot but I don't think so.

Thanks again

 

[Vic]

Take it apart and prepare for the worst. :ohmy:

 

[eagles22793]

the crank shaft or the piston rod could be broken but you would have to split the block and find out.

 

[Dobey58504]

I'm still in the process of splitting the cases, but looking for a crank and rods on ebay. Also, since I have a year or two before my son starts riding, could you also email me the 1st gear activation?

 

[Vic]

I'm still incould you also email me the 1st gear activation?

It's all in this thread.

http://www.dirtrider.net/forums3/showthread.php?t=104498

I have nothing more.

 

[Dobey58504]

I finally took the piston off and tried to move the crank and it barely moves. Could the bottom crank bearing be out and the crank maybe be good?