Welcome to the forum and your project. If you start a build thread, you'll get some input from members that may be quite handy. There's a ton of sound knowledge from some of the top members on this forum.
Stock form is fine, but for the track I'd suggest one thing: suspension.
The RC51 is capable of a lot more with properly sprung Ohlins or other aftermarket forks/internals/springs.
I had my forks rebuilt by Kyle, for about a grand they go thru them, put ohlins valving in, proper springs for your weight, and just a little extra for seals and bushings. Best service anywhere.
I think they might still have some rear Ohlins shocks too.
It really takes the bike to the next level, and the support from Kyle is incredible.
Oh yeah, a 55 series for the rear tire too. Lots of folks like a 190/55, I loved it too, but get even better grip with the newer RS10 in a 200/55. On my second one now.
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