I am going to do my third sprint distance triathlon in the fall. I do not have a bike, and probably will not use a bike other than for this tri. I need a road bike to ride 2x per week and for the race.
I do not have the money to buy a nice bike, or really even a nice used bike.

My mother in law has a 1979 Raleigh Men's Road bike that she paid $900 for and used only once.

It is the right size for me...is there any reason why I shouldn't get this bike tuned and use it?

Thanks,
Robin