So long story short, I bought a cheap chain and sprocket set for my 400EX last January and three months later, the chain is worn out. I need something that will last awhile, what do you guys recommend I buy? Also, will I need to change the sprockets on it again since the ones it has are so new?

 

DID ERT2 520 gold. In motocross at least can,t see why not on a ATV.DID ERT2 Chain review - Dirt Rider Magazine

 

DID or Diamond X ring.

 

Best chain? ....
Is it for a carb'd or efi machine?

 

What does fuel delivery have to do with the drive chain? If so, it is carbureted.

 

I was thinking the same thing.

What color is the ATV? LOL

 

Everyone knows that efi will put more strain on that chain ...

 

Care to elaborate? You lost me...

 

I don't think it really matters what type of induction system it has, unless you've gone to an aftermarket air filter.

 

How that? EFI has advanges but a increase in HP is not one of them.

Many motors switch over to EFI from carb but there power out put did not change.