Originally Posted by Fire Escape
You could probably get by without changing anything, perhaps not elegant but functional. The second (and third?) digit of chain size is chain width*, originally in 1/8s. 530 is 3/8" wide, 520 is 1/4", 525 fits in the middle at 5/16". If you wanted to line it up precisely you would add 1/2 of the difference, 1/32" (0.031") as a spacer inside the sprocket. That, assuming that the factory got the engine, chassis & swingarm put together that closely. I will predict that your chain will never know you changed sprocket width.
* Disclaimer: I have no idea what the 8 in 428 chain size means!
Good info, but others that have done the conversion report that they were unable to get the nut tight enough on the shaft to hold the sprocket tight without a washer being added.
Hoping to get the change done today. Was going to work on it this a.m., but my wife wants to go the Super Bowl Village this morning. What I saw last night was enough to make me a bit reluctant. Maybe the rain will keep the crowds down.