Paul asked: What’s the brightest in lumens my light can be? Just got a one that’s 8000 lumens and it seems to be too bright.
There is a minimum distance for visibility for required bike lights.
s. 316.2065 – Bicycle Regulations
(7) Every bicycle in use between sunset and sunrise shall be equipped with a lamp on the front exhibiting a white light visible from a distance of at least 500 feet to the front and a lamp and reflector on the rear each exhibiting a red light visible from a distance of 600 feet to the rear. A bicycle or its rider may be equipped with lights or reflectors in addition to those required by this section.
Apparently there is no maximum intensity. Please see these posts, which include the FHP’s comments in response to the same question.
Other statutes prescribe lighting requirements, but they are for motor vehicles, not bicycles.