I have just recently installed a new crank shaft in my Jinling 250 quad with Loncin 250cc watercooled engine. The only trouble is i cant seem to align the gear shafts back into the blind holes when i put the crank case back together hence i cant get the case to fully close up. Is there any tip or method of getting these little beggers back in line. Many Thanks in advance.

 

When you got the crank shaft, did you check to make sure that it was trued? Just because it is new, don't take it for granted that it was trued correctly at the factory or that it stayed trued durring shipping. Also, are you sure you have the correct crank shaft for the vehicle?

 

UPDATE---- Have managed to get the gears lined up and got case back together but now have problems with the gears. It is either very hard to change gear or it locks up in some of the gears. i havnt put it back in the frame yet i just tried changing the gears on the bench but as i have already said it locks up in some gears stopping the shafts from rotating. Any help or diagrams of gear set up would be a great help.
Thanks in Advance.

 

Make sure that the gears are perfectly lined up in the case. Just a couple of mm's off can cause problems. If you are having trouble closing the case after putting the gears in, chances are they are not lined up correctly. I'll look through some of my books and see if I can post a pic of the gear set-up for you as soon as I can.

 

Definitely sounds like a shim is out of order