.. My 400 is having some issues turning left... When i go to wheelie it pulls left horribly.. Nearly throws me off the road. When i go to turn left i have to lean all my weight.. When i turn right... Its fine.. I rode my other friends 400ex and his steering is sooo-much smoother..

I hear people saying its the tie rods-- or the stearing stem.. How can i find out which part it is.. Thanks

 

I'd first check the tire pressure. Then the rear axle bearings. Then the swing arm pivot bearings. If it pulls to the left when you wheelie, this would have nothing to do with the tie rods. The problem is in the rear somewhere.

 

stand the quad up on its rear wheels and turn the handle bars. listen for any squeaking or noise. if you feel any binding start disconnecting you front end parts till the binding goes away. that way you can isolate the problem parts.