I look at things a little different than other people, that being said, I have not bought a new new motorcycle since 1993 and that bike cost $3999 (the good old days.) So, my used 1991 used VFR with 4000+ miles cost me $4500 26-27 years ago and I am still running it (can you say, "Ahead of the game?") That particular bike I have bought things without looking at prices so much (I get things at 10% over dealer cost and have Fun funds set aside on Ebay.) Without getting into networth ect it is cheap to keep an older bike on the road compared to buying a 15,000 dollar Busa or some other higher dollar new bike (which could possibly get me into trouble here.) BTW I do ride fast here and have a clean zero point license (hope I dont jinx myself LOL.)
When you get a new used bike its pretty automatic that your going to have to lay out some cash for a least tyres, battery, and other ancillary stuff. My 93 had a dead regulator/rectifier out of the box, it had new tyres and chain and sprockets on it (bad master link that was replaced at a cost of ten dollars.) You get the picture, I am not penurious when it comes to spending money on these bikes because once your done, you have something that (sounds like a cliche) you can't buy for money. The build quality of these bikes is really good, they did not cheap out what-so-ever. I like what you did with the fuel lines and how you repaired the tatty carburetor plastic tray. I was able to get OEM replacement fuel lines when I needed them and ended up getting Samco radiator hoses from the UK for both of my bikes.
I did club level racing here in South FL when I first moved down here, did a light weight sportsman and a heavy weight sportsman class. Had fun, they did not have track days when I was involved with it. If I was going to do a track day, one of my VFRs would be the last bikes I would go out on, (and this is where my head is) if you even have a low side accident on one of these bikes, you basically going to be screwed for parts. Plus one of these bikes that I own is called, "First Wife" can you imagine flogging your poor first wife on a track day? I think not LOL. I would get a dedicated track bike if you wanted to go that route, Ninja something or other or maybe a nice 600cc inline 4.