I don't know if it has been shared before. But I wonder this. Will the Z4 spark plugs in the stock kits be able to withstand high revs? Will it work if I buy NGK B6HS? Transport + Oko carb + Reed valve + Windowed piston. I did these. I made the adjustments correctly. But I guess I don't see high revs. I was doing 50km with 36t on the stock engine. Now I'm speeding 55km. This is ridiculous.