Exaust Bridge

[wmc83]

I'm rebuilding my 89 RMX250 and noticed the new cylinder has an exaust bridge are these relieved from the factory now? Also I'm using a std suzuki piston is it nessary to drill holes to cool the exaust bridge or is that a bit of a wiesco only thing? I would rather not do it as I've allready put it all together and I don't lke the idea of drilling holes in cast pistons!

[Lozza]

Drill the holes as you will be buying a new piston AND then redrilling the holes if you don't. Have done this and enlarged bridge oiling holes about 100 times on forged and cast pistons.
Too much oil never killed a 2 stroke.

[wmc83]

How do you go about it? I was thinking of drilling 2 3mm holes about 10mm below the ring and 10mm apart down the piston does that sound right?

[Lozza]

straight to the top of the class, just trace the bridge onto the piston with a pencil. place in V blocks and drill,

[wmc83]

Thanks again lozza looks like the top ends going to have to come off oh well I needed an excuse to put in the rm head gasket I bought