Originally Posted by JAG Racing
OK - Once again, I blew out the outer clutch bell bearing this past weekend. Its like clockwork, it lasts about 4 months only (or 8 - 10 races). This bearing is clearly undersized for the application in my opinion. I am going to replace it every 6 - 8 races from now on as preventive maintenance. In addition, I will start to lubricate it more frequently.
Other than that, the car was flawless this past weekend.
Are you talking about the flanged sealed bearing or the thrust bearing with the loose balls? If its the thrust bearing make sure that you are installing the smaller of the 2 races on the outside. You can't tell by looking at them, but one is smaller in diameter then the other. I couldn't tell until I used my calipers to measure. The most common reason for the clutch bell bearings to fail is a slipping clutch. If you are using a high powered engine you probably need to go to a harder clutch spring and better clutch shoes. Use either the Mugen Grey or the Delta Red shoes. People are using the harder Mugen or Kyosho springs too.
Heres a clip from a post WAYYY back in this thread.
The clutch fix. The way to make the clutch awesome is as follows:
1. Get a Mugen grey shoe or a Red rulon shoe from Delta. This will eliminate most of the slipping. The stock black shoe I estimates slips around 10000 rpm at least. With the red or grey that drops to a few thousand. Very noticable punch increase.
2. I finally trialled the new spring. I am using the Kyosho hard black spring from the Evolution. A Mugen silver will work similarly. The main advantage is that these springs have less winds and you dont need to crank down on them so hard. They are around 1mm shorter. With the HPI spring you need to crank down on it so hard to get good high engagement you start to get spring bind (the loops touch each other) and the engagement sticks. A harder spring wont get the binding.