The 421cc kit is designed to be used with a 4mm long rod stoker crank (58mm stroke, 115mm rods). This cylinder kit has higher port timings for riders who are wanting more mid to top end power. The port specs on these cylinders are 196 exhaust and 124 transfer durations. The exhaust port is much larger than a stock cylinder so peak H. The last bike we put on the dyno with the 421 Assassin cylinders: 93 octane, Shearer in-frame pipes, V Force reeds, 35mm PWK carbs, 6 degree timing advance = 86 HORSEPOWER!
2 cylinders Nikasil plated to a 68mm bore size. 2 Wiseco forged 68mm custom piston with a 9 degree dome angle and custom intake window design, rings, wrist pins and circlips. 2 rubber water jacket plugs. 10 stock style head studs. Our mission is to provide you with the best products and the best service in the industry.
We understand that sometimes, customers change their minds about products that they order or simply do not need them anymore. We also know that customers are cautious about Return Policies since they are often tricky and misleading. The following rules apply to new items.Products must be in original packaging and in a new and resalable condition. Any product that was used or fully/partially installed is non-returnable.
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