Two trail boss Polaris atvs. they have sat for about 4 years. I put in new batterys no power going to any thing. Is there any type of fuse or any thing that could have go bad by sitting too long.

My guess is that Chinese carburetor is not jetted or set up right. It may not even be opening fully. Ask in the Polaris forums. Top speed should be 45 mph.

https://www.google.com/search?q=2001+Trailboss+325

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Polaris won't start!! Lights don't work!! Fix for 2001 Polaris Trailboss 325 left handlebar switch. - YouTube

Polaris won't start!! Lights don't work!! Fix for 2001 Polaris Trailboss 325 left handlebar switch. - YouTube

2002 Trail Boss NO ELECTRIC at all... ' Polaris ATV Forum (polarisatvforums.com)

below show circuit breakers page 32
Electrical/Taillight Parts List - Polaris 325 MAGNUM 4X4 HDS A00CD32FA Parts Manual [Page 32] ' ManualsLib

Question edited for clarity, plus full make model (what it is).
Question moved to our only Polaris Trail Boss category.

That is a lot of stuff to change all in one go. One of those items has caused the issue in what was presumably a running ATV? Always best to swap out one item as a time and check everything runs as expected before moving onto the next, checking after each replacement.

The last sentence is confusing even with my edit. I take it you mean it turns over, it catches the odd time, but won't run. In that scenario, and with all the parts you changed, I would check the spark plug gap and that it has a good fat, blue spark. The other thing is the carburetor settings as per the service manual. Engines only need fuel, compression and a spark at the right time.

I am working on the same machine that has not been running for quite awhile. I'll let you know what I learn. Did you find a manual? Gus

Does the slide move up and down in the carb? It should move freely up and down.. Have a professional clean and set the carb!!!

Here are a couple of posts.
Polaris trail boss fuse box location
This is different year but might help,
http://atvconnection.com/forums/polaris/336771-06-trail-boss-330-a.html

DOWNLOAD POLARIS TRAIL BOSS REPAIR MANUAL

trailboss-manual.blogspot.com/
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if its similar to my polaris it doesnt have a main fuse it has a 'short preventer' which I assume is a thermal fuse of some type. its in a black plastic bag off the red wire coming off the battery.

prob needs a new thermostat