I recently got a 1997 Yamaha RT100. Need some help

[Yamaha1997]

So recently I got a 97 Yamaha RT100, and it seems that whenever I put it into gear, the clutch is slipping. I’m using SAE 90 gear oil. It seems like it might not be good for a wet clutch. The slipping seems even worse when I shift up. Any advice on what oil I should use would be great. I also don’t really want to replace the clutch either.

 

[Okiewan]

How long has that clutch been in the bike?

You can try different weight/type of oil, but it's likely not your problem. As far as what oil, ATF type F (like Mobile One). You can also try adjusting the cable. It's not a big deal to replace the clutch. Open it up and take a look at the basket, any rounded-off edges? How do the plates look? Do the metal plates show any discoloration?

 

[Yamaha1997]

The clutch has more than likely never been replaced. There are two stuck screws on the clutch cover that are stripped, so I can’t really remove them unless I have the tool to remove them with.