06-05-12, 07:15 PM
Stoich is 14.7:1 for gasoline engines. You cannot "set" stoich, it is a standard ratio for perfect combustion. But if you run an engine at stoich it won't last long as it will run too hot, therefore the "safe ideal" ratio is considered to be 13.7:1 and lean/rich is referenced to this. Hence yer maun's dyno printout reading that way.
The last Dyno operator I used had a line on the fuel ratio graph set at 13.7 -1 where as others have had it set at 14.7 - 1 (not the actual fuel ratio setting) . My fuelling graph has always been less then 14.7 - 1 which is rich and as you say is safe. But the last dyno guy said it was running weak as some of the time it was around the 14.2 - 1 mark. I have never had a problem with my bike and the operator at Junction 19 Dyno (used by a lot of the FZ1S guys and original inventor of the Quill T3 cans) thought it was the smoothest and best fuelling carb bike he had ever tested.