JR50 Engine Problems

D

Dobey58504

Member

Feb 16, 2008

4

0

• May 27, 2008

• #1

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

***** freak.

LIFETIME SPONSOR

May 5, 2000

4,008

0

• May 27, 2008

• #2

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

 

E

eagles22793

Member

May 25, 2008

146

0

• May 27, 2008

• #3

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

 

D

Dobey58504

Member

Feb 16, 2008

4

0

• Jun 1, 2008

• Thread starter
• #4

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

***** freak.

LIFETIME SPONSOR

May 5, 2000

4,008

0

• Jun 2, 2008

• #5

Dobey58504 said:

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

Click to expand...

It's all in this thread.

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

I have nothing more.

 

D

Dobey58504

Member

Feb 16, 2008

4

0

• Jun 2, 2008

• Thread starter
• #6

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?