they used the same flywheel setup as in the WR untill 1955 when they changed to the new stronger 55R setup.if you're going to race it i would recommend the S&S flywheels with either stock sportster rods or S&S rods. you have to use their crankpin as the taper is different. the sprocket and pinion shaft are available thru a couple of different companies such as eastern. the pinion shaft for a WR is different than a KR in that they oil differently from each other. one oils thru the side and the other on the end if i recall properly.one of the problems with the WR flywheels is that they tend to get cracks around the crankpin area. always get them magnafluxed during assembly
barry so very true. i have put togeaher 4 s@s flywheels with r shafts. and sportster rods. best way. then u can get parts for crank pin. r stuff getting hard to find mostley wore out. also tapers for shafts and pin lot of times in old wheels they r egg shaped. wr stuff pretty weak.