Alternators and Starters | Bosch Auto Parts Alternators and Starters. 100% New Alternators . Bosch has been a major supplier of new alternators to Original Equipment vehicle manufacturers since 1913. Securing OE certification requires strict adherence to stringent precision and performance criteria. These same exacting criteria are also applied in the manufacturing of all Bosch100% New Alternators · 100% New Starters · View Product Bosch internal regulator alternator wiring diagram The Last VK Sixes had a rigid Alternator upper mounting bracket which means that, unmodified, they can only take Alternators with a smaller radius for the pinch bolt and lower mount, like the Bosch 55 Amp BXH1236A. The Bosch 70 Amp BXH1238A Alternator won't because the pinch bolt centre is 5mm too far away to fit the upper bracket.