How can I remove a broken internal circlip? ?

Although the circlip is located in a motor cycle gearbox, where it retains a small ball bearing within the outer cover, I guess this is a common problem across many engineering aplications. Basically, one of the eyes of the internal circlip has broken off and I am unable to remove the old circlip from within its groove. At the moment, one eye is still in place but it is very difficult to push any small point through the eye because the bearing race is almost flush with the circlip. The overall size is about 37 mm open diameter, judging by the new circlip supplied with a new bearing. Any suggestions, please?