The next step for the GS550 is to relieve the crankcases slightly so that the bigger diameter liners will fit inside. I'd just ordered a new Dremel as my old Draper version was getting a bit tired. That thing has been amazing and I've had it almost twenty years — it's done lots of porting and polishing. Anyway, i was in the process of grinding out some of the casing when the Draper tool finally gave up and spat chunks of plastic out the side. The Dremel came just in time!
If you're wondering about the quality of the deburring tools, sandpaper barrels etc., the Dremel ones are superb! I've always bought the cheaper versions and they wear out in seconds, The Dremel ones are worth the extra cost.
But on with the job.
I found it easier to slip the cylinders over the studs, turn the case upside down and mark where the liners were touching. Then remove the cylinders and start grinding. Bit by bit, they went lower and lower.
