Brad The Bike Boy: Rebuilding MV Agusta F4 mirror mount posts AKA when those stupid little knobs on the bottom break off and the bloody indicators won't work anymore.

Sunday, July 31, 2016

Rebuilding MV Agusta F4 mirror mount posts AKA when those stupid little knobs on the bottom break off and the bloody indicators won't work anymore.

I had an MV F4 come in with one of the front indicators not working unless the screw was almost loose because the stupid little cast on lugs had broken off the bottom of the mirror mount. If you've worked on an F4 you've probably had it happen as you tighten the front fairing mount bolts. Do them up tight on some - no problemo. Gentle as can be on the next one - break. They truly give me the hibbidyjibbidies.

On this occasion I thought I might do some thing about it. I measured the knobs on the other side and they were 5mm diameter, so I drilled the mirror mount at the broken points, tapped some M5 threads into the holes, loctited some M5 screws in (long shank ones with the threaded section precut to the desired short length) and then cut the end off the screws so the desired shank length was left. As per the photos below. I was rather impressed with the results I must say, even if one is a bit angled. It's all done freehand due to the impossibility of holding anything in a fixture. Unless, of course, you'd made a custom fixture beforehand. I didn't have that much time to hand. And yes, the indicator now worked with the screw tight.

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