Don't let all these guys worry you, you don't HAVE to get a Hot Rods stroker crank balanced. Sure, if you have the money and time, by all means, get it balanced, but it is not required, your motor won't be a ticking time bomb if you don't.
I installed a +3 crank in one of my 450R's back in 2007. Didn't balance it, just pulled it out of the box and installed. Have hundreds of hours on that quad, still runs great with no problems. Has a little more vibration then my other 450R with a oem crank, but not a large amount. The only reason I notice it is because I do switch back and forth between the two.
For sure use OEM main bearings though, the one thing I would not use is the Hot Rods bearings, heard of way to many problems with them.
2004 TRX450R, 2008 TRX700XX
(BITD #639 Quad Ironman Expert)
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