Bearings and seals work perfectly for all Yamaha enduro 175's from 69-81

and enduro 125's from 69-81 as well.

Is it possible to split the case and just change the bearing on the mag side without removing everything from the clutch side? If I remember correctly, the screws are on the mag side, so this should be possible, just don't know if it is advised.

I think it's far easier to put the transmission back in on the mag side on a traditional assembly so if you can split the case from the clutch side and you are able to keep everything in the mag side you might be able to pull it off. I'd guess you'd leave the neutral detent in but others who do these with regularity could clarify. I personally, think it would be better to go ahead and tear it all down so you can clean all the mating surfaces up and clean dropped debris up better with both case sides empty. hopefully, you've invested in a proper splitter and bearing installation tool I used the freeze method but would have liked to have an install tool (TUSK) so as not to throw the crankshaft d out of true.

Thanks MarkT I wasn’t 100% sure on the bearings 

On a 175 I always install the trans into right case...  almost impossible for me to install in left case.

I have also removed left case half with right side remaining assembled...  Remove detent spring and ball first. 

Must use a tool to press crank from case...  mag bearing often stays on crank...  go slow and keep case as level as possible when removing.