Never worked on one, but I would be extremely surprised if the RC Valve assembly doesn't pull out with the motor en-situ.
It's a routine maintenance part on a (no offence) cheap learner bike... your average 125 rider isn't necessarily going to be able to afford to have a shop remove the motor just for RC Valve cleaning, and I expect many wouldn't have the tools or inclination to do it themselves either.
Again, my own assumption here, but I imagine it is very similar to the 150 (300) and 250. Look up the relevant page in the Online Parts Manual and you will see a diagram of the 250 components (the 150/300 is similar) and you will see that on those motors the assembly is held in by not much more than the oil seal! The E-clip DOES NOT retain the shaft in the cylinder - it just stops it sliding past the oil seal.
I have some scans of the 125 parts manual here somewhere. I will try to find them and that should give you an idea of what you are up against. I wouldn't expect it to be more than a 30 minute job on a single cylinder.
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Andy.
NSR-WORLD.COM
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