Triumph Exhaust Cam Tach Drive Thimble (1) - 70-4700 12-55742 Boots have 15 ribs and

Boots have 15 ribs and measure (not stretching) 7 3/4" long

Bracket is the "Rear" type which your rectifier and rubber grommet

M Part number is 70-6853 & 70-6854

I will decode this below

Triumph Exhaust Cam Tach Drive Thimble (1) - 70-4700 12-55742 Boots have 15 ribs andUp for grabs today is a new Triumph exhaust camshaft tachometer drive thimble. This thimble fits on the end of the exhaust camshaft to drive the tachometer drive box. With out this part your tach drive will not work! Thimble will replace Triumph part number 70 4700 and E4700. Fits various Triumph twins (TR6, T120, T100, etc). Check your parts book to ensure the best fitment. Please note that this tach drive thimble is sold individually **Features**