crank

[izericson]

could someone please tell me the differance between a stock crank and a stroker crank. like i always hear a +5 or +6. what are the differances? i have a banshee with alot done (carbs, reeds, port, polish, bored out, ect) and now i want a crank but i dont know shit about them.

[creamsickle]

the +4 or +7 is in regards to the length of the stroke over the stock. basically its just a longer stroke. 4mm or 7mm longer then stock. there are usually two rod setups. the long rod which is 115mm long or the 110mm rods. which is why some people say they have a 5mill rather then a 4mill. its cuase they are using a 4mill crank with 115mm rods. the longer the crank the more swept volume. and on a scavenging two stroke motor the more the better(for high rpm power output). you will need to check the degree of your ports to see if you can do a stroker crank. I am assuming you have a play port so you should be fine, but if the exhaust port is too high then, well you are kinda out of luck. you will have to get some custom cut domes though, if you want to get a stroker crank. usually its easier to get the stroked crank done then after that get the port to match, rather then the other way around. and if you go to anything bigger then a 4mill crank you are going to need to get the cases trenched out so that you can accomodate for the larger stroke.