maybe yours?? each to his or her own,Unless the 89 is ethanol free, then there is no advantage using it over 87 octane, except it will drain your wallet quicker.
you just named issue by nailing it on the head! NAME brand labels over no name, shell.sunoco. exxon/mobil. no name or off brand, simply don't have the additives of the better named gas, personally my cars get shell or sunoco. which for me means a 15 mile drive to the highway as all we have in town local is off label stations run by not so great people and found to have at times well over the posted 10%.not sure on you location - but in Ontario Shell Premium is the only non ethanol fuel i'm aware off. This is what all the small engine shops suggest people use in their mowers and blowers etc. (but not for the octane rating) I'm sure it will run great with 87. This is what i do / but i make sure my last tank is Shell Premium before storage
I believe there is no evidence using octane higher than recommended has any substantive impact on an engine. While it's true 89 octane is better than 87 in higher compression engines as a general rule, that doesn't mean 87 octane isn't fine for those engines that recommend it.maybe yours?? each to his or her own,
but 89 is a way better choice over 87 in any of today's motors due to higher compression ratios needed for emissions, it makes less carbon inside the chambers and on the valve heads and stems, holds some of the high test additives not found in 87 as it a pump mix of both grades,
machines i work on, the owners get told forget what the owner's manual has printed, run high test as it stores longer and better, we get them back for normal service with very few returns for fuel related issues due to poor quality, no name cheap gasoline, when we do we find the 10% grain has sucked up moisture out of improperly tightened fuel storage can vents and caps. water in the machine gas tanks,
Thanks stromr. I know there are other variables involved, but I will continue to question if there is an actual loss of performance in using too much octane.old flatheads, 7:1, new OHV, 8.5:1
believe it or not but 2 strokes have higher compression ratios than most think, 93 in them is almost a must, and reason the premix cans are 92.My 4 stroke engines get 87, and my 2 strokes get 93.
Only exception is I use 93 in the Honda 1328.
Some of my machines get fully drained of fuel, but most get a full tank of stabilized fuel and the carb bowl dropped and drained.