create change request of type "Risk" using OSLC-java client api

Question

I am using eclipse lyo java api to create work item in RTC , I am able to create the work items of type task/defect using the below code:

            CreationFactory taskCreation = client.lookupCreationFactoryResource(serviceProviderUrl,
                    OSLCConstants.OSLC_CM_V2, task.getRdfTypes()[0].toString(), OSLCConstants.OSLC_CM_V2 + "task");

            CreationFactory taskCreation = client.lookupCreationFactoryResource(serviceProviderUrl,
                    OSLCConstants.OSLC_CM_V2, task.getRdfTypes()[0].toString(), OSLCConstants.OSLC_CM_V2 + "defect");

But I am unable to create the change request of type Risk, Please help