There is an issue with the serialization of the width property of the minor/major ticks in RadRadialGauge - it serializes as the size property. In a scenario when the width and size properties are both set, the width has precedence over the size.
We are aware of this issue, however, I cannot provide with any time estimates for the fix, as our developers are currently working on tasks with higher priority. For the time being you can evade setting the width property.
the Telerik team
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