America New To Me America- Lots Of Front Dive?

New to triumph, and back to riding after a long spell.

2007 America. Runs good, has had the air pump disconnected, supposedly a carb upgrade, new tires.

Problem, seems like a lot of front end dive, both when front brake applied and if I just bounce the front end while sitting still.

Seller of the bike says he put new oil in the fronts, and may have put in too light of oil.

Looking for a little advice on fork oil weight- and how to set it up. Solo riding, but I'm a little big- 6' 6" around 230lbs.

Thanks all, and here's a picture of my new to me ride

 

Thanks for the advice guys. I think I should get the forks out this weekend.