SteveSr
Addicted to ArboristSite
"Upgrade" can mean many things. I was thinking spur to rim.On the 026 they did not do an "upgrade" to use a larger bearing, it's just you need to buy a whole kit to get a 026 Stihl OEM clutch drum.
The clutch drum is different 1121 series (026) vs 1125 series (034/036).Interesting thought though, would the 036 upgrade kit fit a 026? I'm not sure if the drum would be compatible with the 026 clutch/oil pump. The bearing is the same on 026 and the original small 036 bearing (10 X 13 X 10). Drawback would be you must use rims with more pins ( e.g. 9-pin 0.325). Maybe for a hot rodded 026 that would pull it.