MY YS .53 was in a crash recently. I bent the needle valve, and sheared off the threaded portion of the crankshaft that the prop nut would thread on. I ordered a new needle valve and prop washers, etc. but didn 't notice that the threaded part of the crankshaft was gone. This may be a dumb question, but is there any way to replace just that portion without getting a complete new crankshaft assembly? Thanks, Jim