Gas Octane

[CanadaboyA]

Gotta ask.
2003 - 1600cc
Regular 87 or do we have better spark with mid or even higher ?

[Lug Nut]

87 period. Only if your in extreme heat then maybe 89/91. But 99% of the time 87 is what you want and ethanol free whenever possible.

[Tropicalrs]

If’n you just want to just throw $$$ in ways other than chrome at your bike, most expensive octane possible. But 87 is sufficient.

[Lug Nut]

If’n you just want to just throw $$$ in ways other than chrome at your bike, most expensive octane possible. But 87 is sufficient.

Not really... More octane than needed makes deposit on tops of pistons (burns to slowly)... Not recommended.

[Tropicalrs]

I didn’t say tongue in cheek, but thought it was obvious. Other than 87 octane is not recommended by Yamaha in the owner’s manual.

[Jclevesque]

87 and have been using Shell gas cause they advertise without ethanol here in NB.

[roadiemort]

https://driving.ca/auto-news/news/wh...-your-gas-tank

[Shores]

High octane is used to suppress combustion for high compression engines like Harleys and others. Our engine is of low compression design. High octane is not necessarily better fuel for all engines, it depends on the compression of the engine. Use what is recommended in the manual.

[ZeroTurnZed]

My Yamaha dealer recommended 91 no ethanol. I now know why. Here the only ethanol free gas is 91. No 87 non ethanol available. Up in SD every station had 87 non ethanol.

[Shores]

My Yamaha dealer recommended 91 no ethanol. I now know why. Here the only ethanol free gas is 91. No 87 non ethanol available. Up in SD every station had 87 non ethanol.

You're still wasting your money. 87 with ethanol is not going to hurt your engine as long as you don't just let it sit for a couple years. And those issues are only that it turns to gel or attracts water. It does no real damage. I just treat about every fourth tank of 87 with some seafoam or techron. The ethanol will damage some older carburetor parts such as o-rings, etc but our carburetors and injectors are designed to handle the 10% ethanol.

[Chooch]

Good point Shores. 10% ethanol is the MAXIMUM amount of ethanol that is safe to use in your Road Star and most any engine you own. Check the pump before you fill up and if you see E15 move on.

[Duke]

Steve, I'll have to say myself, I wouldn't let alcohol fuels of any percent set in my bike for no longer then 3 months, unless you have added a fuel stabilizer in it. Don't ask how I know this! Lol.

[CanadaboyA]

Ok on the 87.. Had to ask.
Thanks for the tip as well on the seafoam.

[ryanjam]

In upstate NY the only ethanol free fuel is 91 octane, would long term use of 91 octane in 06 AV1700 cause excessive carbon buildup in the cylinders? I do run it out from time to time and seems to run better.

[jrbk]

87 with ethanol is fine, just add stabilizer. I am in VT and it is the same case.

[Shores]

Go to www.pure-gas.org to locate non-ethanol fuel in your area.

[Mrhavasu]

I have always run 91 and never a problem.

[mlrz24]

Wouldn't it matter what mods he has too? Such as jetting, exhaust and high flow air filter? Let's face it today's gas is garbage compared to the old stuff. I'd say 89. It's only 2 more octane because it's probably closer in quality to 87 octane back in the day.

[Duke]

Dave that is true for the fuel injected bikes engineered for today's fuel, but I think in 2001 most fuels didn't have alcohol added to it. I agree that 87 is just fine for a stock engine, but I'd never let this fuel set in my tank for over 3 months, "Max".

[davej]

Duke this is what I found about E10
When was E10 introduced in the US?
1990
E10 was first commercialized following amendments to the Clean Air Act in 1990 that mandating the sale of low-carbon fuels in areas suffering from unhealthy levels of carbon monoxide. Today, E10 is sold throughout the United States.

[Duke]

Thank you Dave, I don't remember ever seeing the alcohol tags at the pump back then. Guess it shows my age? Lol.

[ryanjam]

Thanks for the info, remember going through hell with carbon build up on low compression carbureted engines in 70s where premium was used. Especially the big blocks in police cars and motor homes. . We literally installed water systems on them to keep them clean. Without it they would develop a knock ! And require a carbon job. Guess I’ll try some 87 and use some Seafoam.

[davej]

Kinda hard to compare most 70's issues to todays issues but not this one. But you are correct premium fuel in low compression engines has never been a good idea. Fuel has changed and oil has changed to correct some sludge issues. I remember pulling apart engines with big sludge balls under the intake manifolds and oil passages being completely plugged with sludge from the oil quality of those days.

[BubbaKahuna]

Kinda hard to compare most 70's issues to todays issues but not this one. But you are correct premium fuel in low compression engines has never been a good idea. Fuel has changed and oil has changed to correct some sludge issues. I remember pulling apart engines with big sludge balls under the intake manifolds and oil passages being completely plugged with sludge from the oil quality of those days.

I remember watching my Dad do a valve adjustment on the family wagon some time in the early 70s.
The whole rocker assembly looked like it was covered in asphalt.
Oil technology has come a LONG way since then.

[davej]

yep that was some nasty stuff back then.

[Duke]

If you have access to 87 no alcohol fuel, then that is when a stock engine will get the best fuel mileage.
Alcohol in fuels add octane, but requires a little more fuel per HP.
I have seen what 10% alcohol did in my 2000 RS, and it did cause a clogged up in the main jet and emulsion tube in under 3 months. It might have been the fuel purchased, but have been using that fuel, 90 octane w/10% alcohol at the same station for years. Now that they offer 91 w/no alcohol, I use it, due to high compression pistons in my bikes. When it's cool outside I'll run 89 octane as long as I'm not getting any spark knock.
If a bike is getting any spark knock, I would go up a couple of octane points, or watch how you are useing the throttle when powering up.

[Bikerron]

Since the TPS plays a role in telling the ECU how much throttle is applied and adjusts the timing accordingly (similar to the old vacuum advance) and the crank sensor communicates engine speed (similar to the advance weights in a distributor) and since they’re adjustable, has anyone ever ‘bumped’ the timing on one?

This is not to say go out there and jack with it, but folks that knows the inner workings have had to at least thought about it.

[davej]

Dyna 3000 can bump the timing.

[Bikerron]

Been doing some reading of the effects of timing on exhaust emissions and it seems NOx readings really take a jump with more advanced timing so I’m wondering if they sacrifice a little power by backing it off to appease the EPA gods.

[CanadaboyA]

Pulled the side covers off my 2003 CND model and saw this label.
91 octane ??????
Xshplane that now.
LOL

[Bikerron]

Pulled the side covers off my 2003 CND model and saw this label.
91 octane ??????
Xshplane that now.
LOL

in a nutshell.

RON is an European grading.

AKI is the average of RON + MON. The publicly posted octane Anti-Knock Index rating primarily in the U.S. and Canada

regular gas is regular gas, and 91 RON in Germany is equivalent to 87 AKI in the United States.