Thank you for your question.
I can understand wanting to repair you Dyson vacuum drive belt.
This is a complete system and it is not designed for the consumer to repair. The clutch drive system is designed to service by a Dyson repair station.
If you have taken the bottom plate off then you can examine if the clutch has seized up or if the roller belt is broken and needs to be changed.
The part number for the belt is: 902514-01.
What can happen are the bearings on the end of the roller get bound up with debris and if you take the bottom sole plate off you should be able to get the roller out and remove the end cap bearings and clean them and return to the vacuum.
If you do not feel confident repairing this problem yourself, then you can have it repaired by a Sears technician. Here is a link that will provide the nearest drop-off locations:
Sears Home Services
I hope this will help
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