Here we have the six shoe, friction lined 090 clutch. One of the strongest, clutches you will find on any saw period. If your clutch is worn you with been losing drive (traction) to your chain. So a replacement may be what you need.
This is the cheapest you will find this part anywhere in the world. Keeping your classic saws running... The item "STIHL 090, 090G Genuine Clutch Assy. # 1109 160 2200" is in sale since Tuesday, August 28, 2018. This item is in the category "Home & Garden\Yard, Garden & Outdoor Living\Outdoor Power Equipment\Chainsaws".
The seller is "outbushman" and is located in Bunbury, WA. This item can be shipped worldwide.