well you dont need bearings for the j arms if your just gonna use em for a month, go to yamaha and just buy 4 new plastic bushings that'll hold you over, wait and go right to the extended aarms, save you some time and money from gettin the stockers first, there are afew people on here that have dont the j - a arm conversion, meat makes and sells the kits, 89 bansheedude's workin one a conversion right now and i did one in fall. you can use 1 inch pipe like 1/4 thick. i made it with flat pieces instead of piping, ill try to get up some pics, but for meats go to www.thebansheezone.com and he's got it on there, good luck