i have an 03 kodiak 400 4x4. I replaced the belt about 4 months ago with a dayco high perf belt and i also cleaned the primary pully assembly, regreased it and put it all back together. It all worked fine until now. it feels like it is slipping under strain(in the mud) or when i take off hard. Are the dayco belts any good ? do i need a new one already?

 

Those dayco belts are better than that. But if you disassemble it, you can check for wear, and narrow areas.
Why did you replace the belt, the originals should last 10 years? Im just curious. Do you have oversize tires?
As long as the cover is off, to inspect the belt, relube the weights. If they are dry the clutching wont work right.
Whats happened lately...did the tranny get water in it?

 

the orginal belt actually snapped and shreded up. dont know how. I do get water in there somtimes but i drain it right out. I run stock size tires but the rear has itp 589's that were given to me that are half wore down. The only thing i can think of is that since it doesnt have a low gear it puts to much strain on it? I did regrease all the weights again about 2 rides ago because it wasnt working right. i wasnt getting all my speed but the motor was reving....I also notice that when the belt is working properly it feels as if there isnt enough power to spin the half worn down 589's in thick mud. When the belt was new it would bog down but now it just slips and smokes.

 

Your weight ramps could have a mud grease build up on them keeping the weights from moving like they should.......If your going to treat it like a sub you really should snorkle it.
Measure the belt and make sure its still as wide as Yamaha recommends

 

Thats a problem with the quads that dont have a low gear. When traction is increased...something else has to take up the load...and its usually the belt.
Id start with inspecting the belt, see if its worn below the low limit, or is glazed. If it measures in specs. id keep using it. 1.09 " wide is the low limit, and new the belt is about 1.185 wide.
You might want to look into the wieght and spring kit, for increaseing the rpm at lower wheel speeds. Thats not a cheap fix, but it works. If you have access to a lathe, or know someone who does, remove some of the material from the id of the weights, and itll do the same thing. Taking about 2 to 4 grams off of every other weight, should liven things up, but it might also cut down your top speed.

 

It may be slightly too long and riding too high on the sheaves. I have heard of that happening because the dayco belts aren't the exact size if the original.

 

it worked fine when i first put the belt on

 

Ive noticed that the Dayco belt is longer too, but its also wider, than a stock, new yamaha belt, so it probably evens out.
If it worked fine when you put it on, then either the belt is worn, or the weights need cleaning and lubing.
Its odd that the original belt shedded up, I havent heard of that happening on any other yamis. Im wondering if the pulleys are alined properly.