Printing group of a printing press, as well as a printing press

A printing unit of a printing press comprising:

• a first forme cylinder;
• a first transfer cylinder cooperating with said first forme cylinder;
• a second forme cylinder;
• a second transfer cylinder cooperating with said second forme cylinder, said first and second transfer cylinders cooperating with each other and constituting a first printing group having a first printing position in a print-on configuration of said first printing group;
• a circumferential shell face on each of said first and second forme cylinders and each of said first and second transfer cylinders, said circumferential shell face of each said forme cylinder substantially corresponding to one section length of a printed page;
• at least one axially extending groove on said shell face of each said first and second forme cylinder and each said first and second transfer cylinder, each said axially extending groove being an opening in said circumferential shell face and extending in a circumferential direction not more than 3 mm;
• rotating shafts of each of said first and second forme cylinder and each of said first and second transfer cylinders, all of said rotating shafts of said first and second forme cylinders and said first and second transfer cylinders being located in a common plane in said print-on configuration of said first printing group;
• a web passing through said printing position of said first printing group and defining a web plane, said common plane being inclined at an angle of between 75° and 80° with respect to said web plane;
• a linear guide device supporting at least one of said first and second transfer cylinders for movement of said at least one of said first and second transfer cylinders along a linear actuating path into and out of said print-on position;
• and
• a second printing group positioned on top of said first printing group and cooperating with said first printing group to form said printing unit as a printing tower, said web plane being generally vertical in said printing tower.