[Skywatcher]

Can anyone which fuel octane in Australia they are using I tried 91 a couple of times on the back of reports people using 87 in USA buy noticed last night when warmed up the idle was a bit strange with a sort of engine bump / pop every second or two randomly so may go up to 95

 

[mzflorida]

Can anyone which fuel octane in Australia they are using I tried 91 a couple of times on the back of reports people using 87 in USA buy noticed last night when warmed up the idle was a bit strange with a sort of engine bump / pop every second or two randomly so may go up to 95

I cannot comment on the fuel octane rating in AUS but when is the last time you changed your air filter? That sounds more like a mixture than octane issue.

 

[ctxdock]

Different type of octane rated fuel would not cause this.
ALL gas burns the same no matter the octane rating.

 

[CTX2fer]

Without opening the Owners Manual that came with my bikes I think I remember the call for 91 octane (premium fuel) to be used. I know there are many opinions on this subject that may oppose what I'm saying but the suggestion of a better grade of fuel will not harm your machine. Personally, I try to keep "non-ethanol" (90 octane) in my bike for around town in an attempt to try and prevent the absorption of moisture while sitting in my garage. If I were on the road I would use 91 octane because I know I would run it out quickly and refill soon.

 

[Skywatcher]

The bike has just had a major service so the air filter is brand new allegedly. I will put some 95 in on the next fill to see if it makes any difference.

 

[Vulcan Mediator]

Without opening the Owners Manual that came with my bikes I think I remember the call for 91 octane (premium fuel) to be used. I know there are many opinions on this subject that may oppose what I'm saying but the suggestion of a better grade of fuel will not harm your machine. Personally, I try to keep "non-ethanol" (90 octane) in my bike for around town in an attempt to try and prevent the absorption of moisture while sitting in my garage. If I were on the road I would use 91 octane because I know I would run it out quickly and refill soon.

Nope. Unleaded fuel only, Recommended octane Pump Octane Number 86 or higher. P 42 for 2014 Owner's manual for CTX 700 N/NA, ND and DCT. As this book is not in French, and references both a Canadian website and California standards, I would say this is for all North America.

 

[Skywatcher]

What most likely would cause a lean mixture

 

[ctxdock]

How do you know its running lean?
If it is running lean you might have a vacuum leak, and that would also cause some rough idling, AND unsteady jerkying while going down the road.
How many miles?
Maybe try some fuel injector cleaner.

 

[Skywatcher]

It's not jerking it's just a slight stutter in the idle every second or two when warmed up fuel injector cleaner you add that to the fuel?

 

[mzflorida]

The stutter or pop; it is only at idle and not while at speed or under load? Timing, or IACV. Check both. Timing is easy, IACVs are usually a pain in the hind side on any vehicle including motorcycles. It is going to be on or near the throttle body. You said it had serviced recently. Maybe the tech hit the connector? If that connector for the IACV is loose it would be enough for the problem you describe. I THINK that the IACV valve throws a code when it is having problems.

 

[dgall]

Can anyone which fuel octane in Australia they are using I tried 91 a couple of times on the back of reports people using 87 in USA buy noticed last night when warmed up the idle was a bit strange with a sort of engine bump / pop every second or two randomly so may go up to 95

I would start with the possibility that you just got some bad or contaminated gas from the gas station. Over the past three years I have run nothing but the cheapest 87 octane ethanol gas in mine with out any issues. I would run the tank down and fill up at the newest and busiest brand name gas station you can find and see if that makes a difference. A busy station has good fuel tank turn over and a new station will most likely have the most up to date UST monitoring system. If the pump is dispensing really slow where you buy gas when filling up, it’s an indication that the filter may need to be replaced due to fuel contamination.
“ If fuel that has completed phase separation passes through the filter, a specially treated polymer inside the filter expands and congeals, increasing the total differential pressure, which significantly slows the flow of the fuel. Similarly, if the filter senses water, the filter reduces the flow”.
Your Dispenser Filter Might Be Trying to Tell You Something - Fuels Market News
Underground Storage Tank (UST) Monitoring Systems

 

[Skywatcher]

I have made a video to demonstrate the random phut noise heard from the exhaust. I have put high quality Ron 95 and it still does it. May be its normal to make this noise can someone confirm this.