The B7 idler gears are machined out of self-lubricating plastic so they are perfectly true and allow the transmission to spin much more freely. 

Information 

We have tested these for a couple of months with amazing success. The only time we could strip them was on a very high bite carpet track, with a direct drive, and the gear diff in the highest 3 position. The way the AE transmission is designed is that in the higher positions you are increasing the gear mesh gap and the removal of the slipper put a lot of strain on them when landing at full throttle. They were also tested on the same track in mod with a slipper and there were no issues. 

Details

• Machined from self-lubricating plastic for a completely true spinning gear.
• 26 Tooth.
• Uses the standard 5x10x4 bearings.
• Direct replacement for AS92421
• Includes 3 idler gears.