I have some knocking noise coming from my engine and the wheeler smokes as well so from what i can gather the piston rings are probably worn thus creating slap from the piston and the smoke being created as well. There is no water in gas so this is my conclusion on noise.

Anyways, i am doing this myself and am about to order some new rings, maybe a piston to, but how do i know which rings to get. I see all over ebay and elsewhere rings for a 450s (2004) that fit the factory specs but there are so many differences in the rings that all claim to fit the stock oem piston. Like .90mm, .025mm, .075mm. Not sure if these numbers are correct, but will all the rings work, should there be a certain size or measurement i am looking for, etc? Thanks

 

I'd say it's best to order it from here to make sure you get the right parts...

http://www.oem-hondaparts.com/

 

well you will want to measure the size of the piston and the bore using a micrometer or vernier caliper and once you get the piston and rings ect you will want to check the ring gap by putting them into the cyclinder by themselves without the piston...you will also need to get a ring compressor along with a torque wrench,snap ring pliers, feeler gauge, and spring compressors for the valves