New to biking and wondering does 92 octane help the bike or it doesn't matter thanks  Petervt

Yep...what old.indian said.  The low compression engine does not benefit from the use of higher octanes.

It can benefit from the use of name brand fuels - which have more additives than economy brands.  The detergents and additives in the name brand fuels help to keep the valves and combustion chamber clean.

You can use the cheap stuff. It's a low compression engine.

And, I know you're new and all, but I am kinda the self appointed grammar police, local smarty pants, hassler and heckler and I wanted to welcome you and go ahead and break the ice.
And, by the way, petervt is not how you spell pervert,but those of us who are a bit lysdexic unsterdand.

I most definitely believe you guys and it's really good to know that I don't need to put premium gas in my stock S40. And I found a station about 6 miles up the road from my house that sells ethanol-free gasoline that's not much more expensive than regular gas. But still..... I wonder why the sales manager of my local dealership told me to "ONLY USE HIGH OCTANE" if it's not really necessary. This is just 10 days ago, mind you!!  

It almost made me feel like I'd be some kind of low-life or cheapskate to put such "inferior" fuel into my shiny, new, vulnerable baby boulevard and take the chance of it beginning to run like crap-o-la.  

While I agree that technically these docile low-compression engines only require 87 octane (as stated in the Owner's Manual) if you ride in a lot of slow or stop-and-go traffic in very high heat and you like to hammer your engine with the stock lean carb listen for detonation/pre-ignition.  In that case a little higher octane is good cheap insurance to prevent detonation/pre-ignition.

On our air-cooled dirt bike engines head temperatures can soar when the going gets slow or stopped.  Our builders/racers/tuners all recommend higher than 87 octane even with the low-compression 9:1 stock piston.  That is because the stock cam is so short/small that it builds very high cylinder pressures at very low engine speeds.  All that being said, dirt bikes tend to see far more abuse than our street singles.

Kris01 wrote on 06/27/16 at 17:12:19:


---------------------------------------------------

You might be right about needing to change dealers but in a relatively small city like Raleigh, there's only one other dealer nearby and I've heard BAAAAD stories about that one. High pressure sales folks, ripping people off by doing unnecessary work, etc.

Honestly, if I can learn how to do some basic work on my S40, then I'd like to visit the dealer as little as possible. One of the first things I'd like to learn is how to clean the carburetor correctly (and maybe replace that factory petcock). I'm not very mechanically inclined but normally I pick up on new stuff pretty fast. About the only thing I've done on my cars is change the oil, rotate the tires and replace an occasional set of front brake pads.

RaleighGuy wrote on 06/28/16 at 04:57:43:


Keep repeating that to yourself!