Tuono V4

The pin sizes are listed because of inconsistencies by Aprilia on the steering tube across the range of RSV4 models. Exact pin specs are proprietary information, but use the #31 pin if your steering stem hole is roughly 19-20mm(on up to the '20 model year). Use the #47 pin on 20mm holes(on the '21+ models). Use #25 if it is roughly 16mm. Use #15A if it is roughly 27mm. If you are not sure, give us a call at 256-533-1977.