I got round to doing a few jobs on one of my bikes the other day one of which was replacing the crankcase breather valve. 1984 R80ST. I’ve never needed to do this before despite countless airhead bikes owned. Still, it was making the classic ‘Turkey Gobble’ noise I’d heard about. Getting the old one out was a struggle. I ended up making a tool and using a slide hammer to jerk it out. Heating the casing had no effect too much metal to heat I guess. The new one, same style as the old one, Reed valve, just plopped in! Still buttoned it all up. Test ride, still making the same noise. Any thoughts? It’s clearly a one way valve opening and shutting due to crankcase pressure allowing excess pressure to vent via the air box but why one way?
