Crankshaft Doppler ER1 Minarelli AM6

Crankshaft Doppler ER1 Minarelli AM6

The Doppler ER1 is an affordable full-circle crankshaft with acceptable build quality. According to Doppler, the ER1 is rated to withstand up to 15,000 rpm. In the past, however, a weakness in the connecting-rod bearing has been observed.

For that reason, we recommend using this crankshaft only in 50cc–70cc sport engines. For 50cc–80cc mid-race and high-end setups, it’s better to choose a Barikit crankshaft or the Doppler Competition instead.