Gasoline....low, mid or premium

[davidhollinger]

Originally Posted by alangoff

premium with no alcohol here....will get enough better mileage over e10 to pay for it plus the higher octane sounds good....just remember high octane means resists burning/igniting so when it is in the 20 or 30s here in wisconsin my 2002 nomad is rather cold blooded on it...and i have took apart enough engines that had predetination damage that i would worry about it....

I have the exact same bike as Alan, even the same color. When I first bought it I ran only Premium 93 or the Non Ethanol. It ran OK on the non ethanol but pinged and backfired on decel BADLY on the 93. I tried regular old 87 once and it ran like a dream. I use MMO in every tank and seafoam once in a while as well and have no issues. I dont mind paying for higher cost fuel but in this case it was actually worse on my engine.
Side note.. my bike is stock.. no fuel processor or aftermarket pipes, or intake mods.

[davidhollinger]

[QUOTE=macmac;522773]How is your bike set up? Of it is stock you better be burning hi test fuel to even out the burn.


The problem when you have a all stock bike that PINGS on high test then you have a big problem and my 01 did!


Mac, what kind of issues..??

[macmac]

[QUOTE=davidhollinger;522938]

Originally Posted by macmac

How is your bike set up? Of it is stock you better be burning hi test fuel to even out the burn.


The problem when you have a all stock bike that PINGS on high test then you have a big problem and my 01 did!


Mac, what kind of issues..??

i read both your replies.... can't explain why a stock bike doesn't PING on regular but will on hi test.

Issues i had was PING on any grade of gas with the 01 stock. it started to knock like a bitch in 2nd gear and stayed that way in 3rd on hot days. Lugging in 5th (2nd over drive) it was OK, but not much fun.

PING is flame cutting of the little things like piston tops, piston edges the top comp ring, valve edges and valve seats. Think of PING like a little demon with a big hammer and a sharp chisel .

Trying to accelerate in too tall a gear can create the right criteria for ping.

I found that out, while I knew it anyway, last week pulling off the road into a rough dirt parking lot in 2nd gear. Sometimes i forget that I am not in 1st gear when I pull off the road on too hot of a day

My opinion of too hot a day looks like this

getting up out of that parking lot starting in 2nd gear because that safety neutral finder doesn't like to let you fish for 1st stopped was the pits!

That engine Pinged hard twice. but I was doing something that engine should not have to do.

[davidhollinger]

I think we have all tried to accelerate in too high of a gear. If I am passing someone and dont downshift then I hear it knocking or when I am in 5th gear and start climbing the hills here.... it gets bad then, but just around town I have no issues. I like the bike starting right up on cold days so I dont want to mess with the ICS. The only thing I would like is the coaster plates to clean up the rats nest in there but I dont have the skill for that.

[macmac]

Originally Posted by davidhollinger

I think we have all tried to accelerate in too high of a gear. If I am passing someone and dont downshift then I hear it knocking or when I am in 5th gear and start climbing the hills here.... it gets bad then, but just around town I have no issues. I like the bike starting right up on cold days so I dont want to mess with the ICS. The only thing I would like is the coaster plates to clean up the rats nest in there but I dont have the skill for that.

Well the reality is these are touring bikes. These bike have 1st, 2nd and 3rd gears....... 4th and 5th are both over drives.

As fast as a Nomad can go will be in 4th or 1st OD. To get there you get there in 3rd and top out in 1st OD. Shifting to 5th or 2nd OD will slow the bike down.

About as fast as a Nomad can go is 112 to 114 MPH on a flat dead level run with no wind.

The ISC's add metered air any times the ECU thinks the engine needs added air.

I am willing to bet I money I ride on days colder than you see if you ride in state in winter. I ride to first salt and don't ride again until first hard rains wash the salt away, but I have been riding in single digits many times.

My ISC's were removed and placed in a box a week after I owned the bike. My spark plugs are at 28,000 miles now and are just starting to have effect on cold starting now. Before now the bike engine didn't crank a beat and just started with a boom. Due to worn out plugs there is a beat or two now before the engine comes to life.

I am gathering the parts I need for the rest of this service. I just did the entire ft end. I had planned to sevrice the whole rear end by now but with wicked heat I have gone swimming and taken the bike to get there.

Once the rear end is serviced mainly for the drive shaft boot, then I will do cam chain extenders and plugs at the same time with now oil(s) (rear gear set) and a new air filter made of cotton.

After that its just back to cleaning and more cleaning for a long time, unless the rear CT wears faster than I expect. I think I will get next summer on that as it is now.....

I may end up installing my Barnett Clutch Spring this season too at some point. I might change my BF again too for grins. That depends on rain... Since yesterday night I have 2 inches more rain in less than 24 hours, less than 12 really.

This BS keeps up and i will install the pontoon kit

[XedoS69]

premium only. $1.00 difference per fill up is not significant enough to consider reg or med.

[BigRed]

A stupid question but what does a PING sound like?

[dshelly]

Sounds like a little man with a hammer beating on the top of
your pistons.

[Netnorske]

Originally Posted by XedoS69

premium only. $1.00 difference per fill up is not significant enough to consider reg or med.

Just keep in mind most of what the manufacturers tell you about which fuel to run in your bike is based on EPA regulations, not on performance.

[1kevin662]

Mine pings and does not run as good on 87 octane...

[macmac]

Originally Posted by 1kevin662

Mine pings and does not run as good on 87 octane...

All stock I take it, or modified with no fuel processor.

[BigRed]

Originally Posted by dshelly

Sounds like a little man with a hammer beating on the top of your pistons.

Thank you

[davidhollinger]

I just filled up with 93 and added 4 ouces of MMO. GOnna check the mileage and listen CLOSELY for any Ping and backfire on decel. If present I will stick with 87.

[MJ07Nomad]

"..getting up out of that parking lot starting in 2nd gear because that safety neutral finder doesn't like to let you fish for 1st..."

MAC, how do you fix that, my bike does that when I stop for gas, I put it in neutral, and full up, go to put it in 1st and it will not go....I have to play around with it and finally it will...its like every time I get gas, bike runs fine otherwise...

Sorry about the high jack....mj

[blowndodge]

It's amazing how much or little people know about the properties of RON (research octane number) and MON (motor octane number). Dave since Mac's Volvo's experience didn't raise you boat in the rising tide of knowledge let me (an ex professional drag racer for 20 years) enlighten you on MON (motor octane number)

Kris was a little off in his discription on Ping, Knock (pre-ignition) all used synonomously by error.

Pre-ignition is not when the combustion starts before TDC Top Dead Center. Pre-ignition is when the combustion starts BEFORE that spark plug sets if off. All modern motors spark their combustions BEFORE TDC to leverage the compression to even higher levels.. That's why advanced timing on engines raises torque output on engines. The enertia from the piston rising in the motor it met by the "explosion" of the combustion before TDC and these two forces act against each other to make a "bigger" BANG.

Problem is, if you think about it is that these two forces "fighting" against each other lowers the maximum RPM of the motor because of it. Less timing means higher potential RPM's but lower torque values usually.

The argument of needing premium so it pushes longer on the pistion in a long stroke motor is false. This difference's in flash points between regular and premium is so small that a long stroke motor would receive probably .000001 seconds more push. Now remember even if is was longer a slower burn is a less powerful burn. Period. Non debateable. If you argue that then "thermodynamics" is not your specialty.

Trust me I could bore you with a disertation on this crap after 20 years but when a motor with less that 10:1 compression ration needs premium it's because the manufacturer took rather large shortcuts on head design, fuel delivery design, piston crown design and ignition design.

Engines that need premium with less that 10:1 compression ratio alson suffer from excessive carbon build up. Higher octane fuel is nothing more that low octane fuel with "additives" that discourage pre-igniton by introducing a non burning componant into the fuel. This is why lower octane fuel actually has a higher BTU (British Thermal Unit) of energy per drop than high octane fuel.

Why does this pre-ignition happen? When the pistion starts it's journey back up the bore on the compression stroke where only the intake valve is open and starting to close, what happens when you compress air? It heats itself through the reduction of area in which it's compressed. Next time you manually pump up a tire feel the heat from the tire pump cylinder. It gets warm. This is happening in your motor as the rising piston is reducing the volume inside the cylinder.

This rise in temps can and sometimes sets off the combustion mixture before the spark plug has had a chance to do it.

It is thermodynamically impossible for a motor to get better mileage on high octane gas than lower octane gas if the lower octane is completely resisting any pre-ignition. Faster flash + more torque (see above explanation).

Some may say they have experienced otherwise. If you have then your higher test fuel has less alcohol in it than lower test fuel or your bike's pre-ignition on low test fuel is severe. I was fortunate to have 3 tankfulls of regular gas in my Vic outside of California and consistantly got 50MPG or 10% better mileage without this alcohol added like is required in California.

Mac is 100% correct. I was just laying some ground work as to why.