My 1997 748 started up this morning just as she always does perfectly.  I let her idle up to temp to do the oil filter etc.Now the bike will not start.  She cranks but will not pop off.  I changed the plugs and checked the fuel connections, and they seem good.I was thinking of checking the air gap at the Hall effect / timing sensor, but I am otherwise stumped as to why the bike now will not fire...It sounds as though the ignition is just not firing as hear the fuel pump prime and those relays seem to be working... Any help would be greatly appreciated! Eric            I had this happen to my 748 and it was the ignition relay, I believe it's the yellow relay on the right side near the starter solenoid.            Another issue when it was turning over but not starting was the injector relays.            Paul                                    Many Thanks Paul,                         I will check the yellow relay as perhaps it got moved when I was adding oil.                       What is the location of the injector relays?  Are those the ones under the seat?                                                  Ciao,                            Eric