Does anybody have any idea what the average fuel consumption of the Ryobi 26cc string trimmer motor is at rated power output (7000K?) Looking to use one for an endurance related project if it sips daintily. Thanks.

I use a small O.J. bottle (12 oz?) with fittings glued into the cap. I leave it on the test stand at a high idle of about 2500 rpm for an hour to hour and a half with occasional partial and full throttle. If it burns 3-4 oz per session that's a lot. I don't know about running at full throttle, but I will next weekend at a fun-fly. Building an alum. muffler, mtr. mt, and prop adapter for this event. Also puting on a JEH ignition setup. I'll try to get some good results and post them ASAP.

Doug

If it burns 5-6 oz/hour that would be phenomenal... Hope so. Thanks.

FWIW the Honda 31cc burns 12oz per hour, full load @7000rpm

Hmm... So maybe 10 OZ per hour... still within reason.

Did you have any overheating problems running full out for any length of time? I'm hoping for several hours of run time, in a cowled situation.

Like any engine, depends on how much power your making.

Assuming a gas 4 stroke motor properly tuned, not rich or lean, it should take from 0.4 ( good) to 0.5 lbs ( average) of gas per hour per hp.

A gallon weighs 6 lbs which is 64 oz, so, if your making an average of 1 hp at 0.5 lbs/hr then a gallon should last 12 hours, or 5.33 oz/hour.

If its drinking faster than that, either your making more than 1 hp, or have poor tuning.

2 stroke BTW will often only get 1.0 lbs/hour/hp, literally 1/2 as good. Alcohol fuel will again roughly double these figures.


Dean in Milwaukee