Bought this battery as a replacement to go in my 1976 YAMAHA RD400c - Battery is a tight fit in the battery tray - goes in but brushes both ends of battery. Its not going to fall out or move because its a wedge fit. Battery terminal screws/nuts are M5 instead of M6. Battery seems to be doing the job OK but its only been in for a week or two and a couple of rides. A real review is needed in 12 months