hi all
i have taken both barrels of and found they both have a crack on the thin exhaust port webs(i think i have explained this probally) does this mean they need to be thrown?they dont look to bad apart from the small cracks.
not happy,it keeps getting worse

Not impossible to repair, but too expensive? Yes.
That crack left as is will eventually catch the ring and potentially destroy the whole motor. Defiantly don't put them back in, get some new barrels, rings, bearings etc. Don't forget to check the service limit of the crank thrust while the barrels are off.

Not quite a real problem nowadays.
The crack needs tig welding and then a new cylinder replating...

Aptec in UK is making a nice job on that matter. They will also send the cylinder with the ports tidied up and the exhaust bridge relieved. Prices are great though you could check for a local option since you are in Au.