I'm guessing I need to loosen the stem, remove it and add some more spacers then reinstall the stem but I don't know what size spacers to buy or if I need to buy a new stem if the OEM stem isn't long enough to do this. It's a 2018 6.0 trekking. If anyone has raised the bars on their Haibike, I'd like to know how you did it and what size spacers to use and where to buy them, thanks.