I use a local guy here within 30 minutes of my home, he owns a small ski / cycle repair business. He has a boring machine and can run down to the .25mm range. He will hone it and chamfer the ports, some machine shops will not do this, be sure and ask. If you want to send your jug to TN he can turn it around in a couple of days. Quality work & quick turnaround at a fair price. LMK if you are interested, he has bored many cyls for me and all of our local riding group. Never had any problems.