when ordering the driven (the rear) remember it must be a 6" for the trail bronc,otherwise the cover I made you will not fit. 20 series are almost impossible to find,I have not tried this set up yet ,but I found a 30 series with a 6" driven,you would have to purchase the driver and driven seperate.MFG in wisconsin carried them,OldMiniBikes Warehouse might have them also,have not looked yet.