My Spindle bolt fell out of my crank on my 2009 kink roc?

what specific spindle bolt do i needMy Spindle bolt fell out of my crank on my 2009 kink roc?
If the bolt fell out, it was never correctly installed in the first place. Without the bolt secured, the crank arm has the opportunity to move on the spindle, thus destroying the precise taper of the crank arm. Take it to a shop and have them reinstall the crank arm properly with a new bolt. If the crank arm's taper has been compromised, the mechanic will be able to tell. I suspect you will be in the market for a replacement arm.