As the debate about the Chinese Blaster cylinders rolls on we at KOR have...


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.

%d comments
  • I have a ported Chinese jug I plan on putting on and documenting everything from leakdown to the first warm up. It was bored to a Wiseco and ported by a pro not by me.

    I can tag you when I post results of it if your curious what they are.

  • So far so good .I would have never bought this cylinder .but it was already on there .Ken took good care of me and we decided to see how long it last ..this thing runs amazing. And as ken said .my son beats the craps out of it every day 22.4 hrs still sounds tight .138 lbs of compression. Scenes day one .I'm sold Thanks KOR for all your help. We will run like we stole it until it blows itself to bits .hahahah

  • 138 is low. I bet it was at 145 twenty hours ago. Keep checking it brother.

  • Who ported it

  • i took one apart where the wrist pin had actually ripped out of the piston. i had never seen that before. i wish i had taken a picture of it before it went for scrap.

  • I took one apart where the bearing shattered. I don't know what kit it was just know it was a knockoff, bought it blown up.

    Didn't have many hours on it according to the previous owners, could have developed a leak from the cheap paper gasket, could have been a bad install, I honestly don't know.

  • . Staying tuned

  • Lol

  • I ported That cylinder hoping you were going to run it MikeHarpster. This way we would see how well a freshly bored Chinese cylinder with wiseco piston would do especially since it was ported and all cleaned up. This endurance test should answer allot of questions

  • I bought the cheap kit and it did this

  • Different gauge. Hahhaahh I guess she's doing better than I thought

  • Any updates?