Hi Naomi,

Unfortunately, there is no other way to cycle to Myrdal unless you take a ferry from one of the towns along Sognefjorden to Flåm (then cycle or train up to Myrdal).
The good news is the regional trains from Bergen to Myrdal (R45) have room for a tandem. You will need to book the train in advance (1 day in advance is fine) so the driver knows to stop at Upsete. It doesn’t always stop there (tiny station). When you book the train tickets, book one bike (you shouldn’t need to pay double for a tandem).