2003 Yamaha Vino 50 Crank Bearing Replacement

[sc00ter]

That sounds weird and interesting! So, the crank split in half... I would press them out I guess, as I have never seen that happen before. Note that the bearings will (should) stay on the crank arms and they cannot be reused, no matter if you get them off and they spin smooth. We can usually reuse the old crank if needed when we split motors. So, press the crank halves out? What crank are you getting to replace it? Going stock or a slight upgrade? A upgraded crank cost a bit more and gives you the worry free option if you ever go with a bbk in the future. What sucks is we recycle the old, stock cranks after removing them. Have zero interest in stock motors.

[msiger919]

Originally Posted by cheapeto

I'm sure you found this already:http://scootermasters.com/manuals/02-05%20Zuma%20SM.pdf
section 1 6th page lists all the tools.
But I did not go through it all.
I'm not near the mechanic as many of you are, so I need a service manual myself, and prefer a good one, when I can find one.
Best wishes in your project.

Thanks for the link, I got the manual now! Noticed a special tool for pulling the crank. I split the case on this scoot and the crank came apart. Each case half has part of the crank in it. I am thinking of trying to press it out with my hydraulic press?

[msiger919]

Originally Posted by sc00ter

That sounds weird and interesting! So, the crank split in half... I would press them out I guess, as I have never seen that happen before. Note that the bearings will (should) stay on the crank arms and they cannot be reused, no matter if you get them off and they spin smooth. We can usually reuse the old crank if needed when we split motors. So, press the crank halves out? What crank are you getting to replace it? Going stock or a slight upgrade? A upgraded crank cost a bit more and gives you the worry free option if you ever go with a bbk in the future. What sucks is we recycle the old, stock cranks after removing them. Have zero interest in stock motors.

This thing was abused. I think they ran it quite a while with bad bearings. Both sides were bad. I could wiggle both the clutch shaft and magneto side. Pull on the connecting rod and you could see the crank shaft moving as well. Piston was a little scored also, but cylinder looks to be OK, cast iron I believe. I am just going to put it back to stock. If I am going to mod something it is going to be an older Zuma, like those scoots.

[msiger919]

Seals and crank are in the freezer. I got all I need to put the motor back together. Starting today.

[msiger919]

Manual does not say what to do first, put bearings on crank first or push bearings into case first.

[msiger919]

Vino is back on the road and running fine, thanks people!