muffles

Do these normally require someone to take the engine out, take it apart, and rebuild it?

I've got a slight oil leak on the CBR at the bottom of the engine, it seems to be coming from the join between the sump and the rest of the engine. Assuming the bolts are tightened to the correct torque, is the only way to fix this to take it apart and re-seal (I think there is some sort of sealing paste or something used, which is what would be missing if the bolts were tight enough)?

It's very slight and seems to only happen when I leave the bike on the side stand, i.e. leaning over on the side the leak is coming from. But it's at the bottom of the engine so I'd have thought it'd always be below the oil level - but that's another question which I will investigate tomorrow at the earliest...

Can you get any kind of radweld type stuff for engines perhaps?!