Please ensure when fitting your new stem that there is a gap of 2-6mm between the top of your steerer tube and the top of your stem's clamping area. This will ensure that your headset can tighten correctly and give your stem good support from your forks.
To help with fitting of riser bars please refer to the additional picture to help split the clamp. You can screw the bolts in backwards and place an object in there such as a ruler or a 2p coin.
TartyBikes Ltd, Units 3-4, Club Street, Bamber Bridge, Preston, PR5 6FN