5 What is the diff erence between old style and ne w style The diff erence betw een old style and ne w style is the r im bac k section design The top bac k section is old style The bottom bac k section is ne w style The top design utiliz es 2 to 4 pr y bar poc k ets f o r med into the bac k section These pr y bar poc k ets are used b y tire ser vice personnel f or breaking the tire off the tire bead area dur ing demounting The prob lem with this design is if the tire is seiz ed up real tight and the r im is suf ficiently f atigued the pr y bar poc k ets can be brok en off The bottom design utiliz es a contin uous pr y bar slot which goes 360 deg rees around the r im This slot is used with a h ydr aulic tool f or f orcing the flange bac k and to push a mounted tire off the tire bead area of the r im The adv antage of this design o v er the old design is that it has more mass than the old style which results in a stronger r im section In addition tire ser vice personal ha v e a m uch g reater ease of doing tire changes utilizing the h ydr aulic tool As a pr actice w e tr y to only stoc k the ne w design r ims in 33 to 49 siz es Old design siz es are a v ailab le b y special request Currently 25 and 29 are only a v ailab le in old design styles