Herb is building a new 750 motor to run at Bonneville Speedweek this summer. This 750 will have the same bore as our 920 engine (81mm), with a 73mm stroke. Here are some pics. Cylinders. Pistons from JS Motorsports, to Herb's design. Cylinders sleeved with LA Sleeve FL80 sleeves, bored to 81mm. One piece crank, 73mm stroke, machined manually by Herb Becker. Here you can see the ring lands have been moved down to accommodate the considerable valve pockets, shown below.