Complex sentence: A common problem with handlebar baskets is that they place the cargo in front of the rider and high up on the bicycle frame, where the weight can throw off the handling of the bicycle and the size can obstruct the rider's vision.
Split into simpler sentences: A common problem with handle bar baskets is that they place the cargo in front of the rider and high up on the bicycle frame. Large objects in the basket can throw off the handling of the bicycle and also obstruct the rider's vision.