In Reply to: Re: Oil, Conventional or Synthetic posted by Dead Eye Dave on December 12, 2017 at 07:07:28:
Honda does not recommend synthetics in their small one cyclinders air cooled engine, since they have no radiator, thermostat, oil pump oil filter and the oil is picked up from the sump by the timing belt and thrown up and over valves AND DECOPRESSION VALVE mechanism , located on valve gear drive.
I just repaired one using synetic oil, that was pure black with low hours of operation. The dirty oil was flung up in the delicate decompression mechanism. causing it to malfunction. Was freed up with PB Blaster.
Synetic oil is not right for "ALL engines" and you could void wattanty, by using a "non recommended manufactures specifications."
Synetics work good in most automible engines however.
The Honda engine was used on a wood spitter.