As the debate about the Chinese Blaster cylinders rolls on, we at KOR have decided to do some proactive research on them. We already know a few things about them. The supplied pistons, top end bearings, and gaskets are absolute garbage. The liners are soft and can be porous on some of them. The cylinder is 10 ounces heavier than a stock cylinder. The port specs are different. The ports need to be chamfered as they don't do this at the factory. The piston to cylinder clearance needs to be checked. My great friend Ron Bushey is running one of these beauties on his sons Blaster. He bought the Blaster with the cylinder already installed. It was loud so we pulled it. We ported the cylinder and modified the head to our normal trail ride specs. We also changed the top end bearing, used OE Yamaha gaskets, bored the cylinder, and installed a Wiseco piston and set the clearance at .003”. The flywheel was lightened and the jetting is spot on. Currently, it's running like a scalded dog. For those of you that don't know Ron, he's a factory mechanic with deep roots at Pro Circuit. He's worked at the highest levels of this sport with some of the best riders in the country. His son is a sponsored rider at KOR and has been beating this bike like an ugly step child for the past few weeks. So far, (20 hours) no problems. I'll continue to keep you informed of the longevity and performance of these cylinders. If this thing holds up as well as a OE cylinder (it won't), you really need to consider the amount of work and parts that went into it. In my opinion, you're buying a cylinder that needs work for $100 and it's substandard to Yamahas product. I understand how these kits can look very appealing to the budget savvy rider but personally I don't see the value when you consider all of the work and parts you need to buy. Stay tuned.