Any help most welcome, thanks for time in advance. I have a 1985 GSX550EF. The bike would only start on easy start then would run well using fuel from recently cleaned carbs. However, compression was very low on cylinder 4, found the gudgeon pin was not secure and had worked to one side damaging the side of the cylinder. Fitted a replacement cylinder, replaced with new gaskets, tightened nuts and bolts too required torque. Compression 160psi all cylinders (Normal range 140 to 190) Set timing using Haynes Manual, TDC on Cylinder 1, lined up cams making sure they stayed in place when tightening. The timing marks on the Cams and the distributor all lined up. Bike now won´t start even with easy start, just keeps backfiring.