OK, so I've done some research on spark plugs and have listed every brand from around the world that has a plug for these 2 stroke bike engine kits. My goal is to make a list that anyone can use no matter where they live. Feel free to add any other plugs that have the physical dimensions of 14mm diameter with 1.25 Threads Per mm and 1/2" reach ( 12mm and .472" reach is acceptable). Heat range and resistance can vary but the physical dimensions should remain within above specs. Spark Plug: Accel - 0453 AC Delco - R44F Autolite - 4123, 425, 275, 4093, XS4093 Beru - 14R-7BU Bosch - WR6BC+, WR7BC+ Champion - L82YC, RL82YC, L86C Daytona Maxfire - 61490 Denso - W20FPR-U, IWF20 E3 - E3.32 Eyquem - 775SX Motorcraft - AER32 NGK - B6HS, B7HS, BP6HS, BP7HS, BPR6HS, BPR7HS, BPR6HIX, BPR7HIX SplitFire - SF265F, SF412C <--- both discontinued - Shucks!! Torch - E6TC, E6RTC Also, for those of you who are looking for a "shorty" plug for a tight fitting engine, I managed to find some 3/8" reach plugs that will fit just fine in the stock heads that came with 1/2" reach plugs. Autolite - 2974, XST2974, 254, XST254 ( The 254 has a solid terminal bud that won't work with the stock cap, if this is a problem, use the 2974 which has a threaded terminal bud. ) NGK - BM7 I've attached a picture of the stock Chinese plug that came with my engine. The picture shows a clear cross reference to a NGK BP7HS. I really learned a lot about spark plug companies while making the list. I haven't heard of some of them until now. DISCLAIMER: Not responsible for any damages. Double check my info before buying and make sure that the new plug matches up with the stock plug that came with your engine unless you're using "shorty" plugs. Have fun and ride safe.