Question about swap to Sport-stem
Forgive the question as a first post, but I recently bought myself a Birdy Rohloff, 2017 model, and am wondering if I made a mistake by ordering the 'comfort-stem'. The dealer recommended the comfort-stem because of my very long absence from bike-riding.
Although I'm enjoying the ride, the best fit I've managed is with the saddle pushed far back on the rails, the seat-post quite high, and handle-bar about mid-point on the height adjustment - just below saddle height. I therefore seem to be sitting too far back, and am finding that I can't ride out of the saddle - which makes the heart pounding steep hills real killers. If it helps, I'm 1.83m (6ft dead), 76.5kg, with long arms.
Q. If I order the adjustable sport-stem (21°) is this installable by me, or do I need the services of a bike shop? The nearest Birdy dealer is an hour away by car. I'm reasonably mechanically minded,and aware that it's an upside down headset arrangement - needed to correct the misaligned handlebar - but my bike experience is forty years' old.
Any suggestions appreciated.
When I've a few more km under my belt, I'll explain why the Birdy was chosen instead of the other 'B-word' 
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