Market timing is really hard. So like everyone says, your odds are better to plunge in than wait, but there are no guarantees - you won't know the "right" answer until it's too late.
Fwiw, 40 is good in that if you keep your skills sharp, you can work and invest year after year until you reach your goals. Experiencing a crash early during that process is good because it means you'll invest at better prices for a while. Allocating your existing savings is a move that you simply do to get a further edge on that as best you can. Good luck!
The real value is in committing to wise action. It's hard to control results, but easy to control your actions. Over time, wise action will pay.