Your mileage may vary, but here's my thoughts from personal experience (i'm sure this isn't the same for everyone):
- My life insurance offered at work has clauses which say that it's only valid if I am killed WHILE at work or doing work activity. Anything outside of that will not pay out to my family.
- I have term life insurance outside of my work plan and I had to answer a pretty lengthy questionnaire, take a physical, do blood work, etc. (typical stuff) They asked questions about all the risky things I do (or don't do), including racing motorcycles and even just riding motorcycles. I didn't race at the time, so was able to answer "no" to racing. I don't do bungee jumping or naked hang gliding either, so I'm sure it all factored in to the premium calculation.
- My health benefits do not exclude any activity explicitly, only certain services (i.e. no chiropractors or accupunture, which is fine with me) and I haven't had a problem yet getting injuries covered, but who knows, the ins co's can deny anything if they want to.
You might want to contact some insurance broker or agent and just talk to them, explain what you do (racing, riding, etc) and ask if there's a policy that fits, if it just means you pay more per month, etc. Even if you don't buy a policy from them, they can probably quote you with info you give over the phone to show you the difference (pending physical, etc).
Whatever you do, I'd check the fine print when it comes time to committing to ensure there's no "get out of jail" clauses in the policy for "risky activities" or stupid stuff like that.
just my $0.02