Yz 125 stator fix - 2003 Yamaha YZ 125

SOURCE: I have a 95 yz 125 head and 98 yz 125 bottom end.

You have a 50/50 chance that they will work okay. All the mounting holes need to line up and the cooling holes as well. Get a head gasket for the '98 and see if all lines up. Will the exhaust pipe fit the '95?

SOURCE: how do i decode yamaha yz 125 engin id number

You don't decode it. It is only a production run series number. Mororcycles are like cars in that respect. It is the frame number, AKA the "VIN number", is what carries all the information. Call a dealer with the frame number and he can tell you year, paint color, specific model and more. They may have a problem if the bike is too old. Yamaha changed to a newer code system a few years back.
Can I get a “very helpful” rating on this answer?

SOURCE: YZ 125 kick starter doesn't spring back

Spring is busted. If you aren't comfortable with piles of extraneous parts floating around, take it to the shop.

SOURCE: yz 125 1990 clutch spring diagram

www.bikebandit.com
It's one of the few that has a diagram.
Not sure what you mean by anti-rattle? The springs are for the pressure plate, and allow the clutch to grab, so you can go.

SOURCE: how much oil to put in yz 125 1999 front forks

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