Ducati Revcounter worm drive /gear drive for Veglia / Smith Tachometer set up.
Ducati Bevel worm tachdrive (1:2 gear ratio ) for Veglia Tachometer set up.
The worm drive gear set will work on all tach drive covers round case 750 ccm / square case engine 900 SS HR 900.
Squarecase tower cover, internal gear can be removed and replaced with this worm drive. When you plan to use a white face Veglia Borletti Tachometer the 1- 2 gear ratio will be the proper setup. Also works setting up Smiths instrument.