Am having problems with new SL. Have a range extender and did a 20 mile ride and finished with 6 bars showing. Took it for a short spin later and with 6 bars it just cut out. Today I used the mission control app 20 miles with 600m elevation again it went from 6 bars and cut out. On both occasions when I put the charger in it showed 6 bars so why does it switch off? Would appreciate some suggestions as am loving the bike, but disappointed with the range.