You have a great looking Simplex there. If you've done everything else, but have yet to smooth out performance, you may need to replace the crankshaft seal. It's located on the crankshaft where it exits the crankcase just behind the flywheel. If that leaks, crankcase compression will be inadequate, causing a weak fuel charge to be pushed up into the cylinder. Best of Luck. Jeff Cooper
You have a great looking Simplex there. If you've done everything else, but have yet to smooth out performance, you may need to replace the crankshaft seal. It's located on the crankshaft where it exits the crankcase just behind the flywheel. If that leaks, crankcase compression will be inadequate, causing a weak fuel charge to be pushed up into the cylinder. Best of Luck. Jeff Cooper
American pickers brought me here. They found a simplex!