I can't seem to conclude from your post, if you wanna race, or do track days, or both..???
Racing is EXSPENSIVE...especially on a 600 or bigger cuzz you'll go through tires so fast...at about 350.00 a set..plus fees, lodging, food, gas ect, ect, ect...and that's if you buy a race preppedbike...and yup there are dangers..
track days is a tad more relaxed, not as dangerous, and cerianly not as exspensive, though it is ADDICTING..
Normally at most rack days, 125cc twin is the smallest bike allowed, and whthere your racing, or doin track days, no one will be laughing....you should see the 2 stroke 125's hat regularly pass 600's, 750's, and yup, even the 1k's, in the turns...
I've seen some fugly bikes at the track, but if you ridie he ride, ain't no one gonna laugh...
While I'd suggest at least doing some track days before even thinking about racing, to ge the feel of higher speeds, riding a close quarters, and gettin passed and passing at close quarters, some people freak out when they ge passed in a turn..
At 57...I sill get SOOOOOOOOO much enjoyment out of riding on the track...I don't race anymore, haven't for about 20 years, but I plan on geting my race license in Nov..and racing a few times each year..I'm self employeed, and can't afford to be laid up for any length of time.....or take off work too much..
There's always some inexpesive race / track bikes for sale on the various MC sites...which can aid in keepin he cost down..i.e., I picked up a race prepped 02 gixxer 600 for 3k with extras...
So...NO your not to old, hell at 41, life has jus begun for you..enjoy it while you can....get out there and have FUN..
Here, show this to your doubters...this OLD geezer is 57 and still draggin knees..