Could someone draw me a picture (lol)? I have a 99 400ex. I assumed it would be like a motorcycle until I looked..and well it dont look one. All I see is 4 allen head bolts but they look like the are holding the housing together.. Sorry if this has been answered before but real could get a clear understanding of how it works....thanks for your help

 

Those 4 bolts hold a bearing carrier. It is excentric and is adjusted by a wheel with slots in it that is on the left side. Rotate the wheel toward the back to tighten chain (a large C-wrench for adjusting shocks works best), and forward to loosen it. Once you have the proper amount of chain slack, retighten the bolts.

Easiest system on the planet! Go try to adjust a Yamaha or Suzuki or a dirt bike, and you will realize what I mean.....

 

are you serious...!! that was to easy....Thank you reconranger