Can't help but feel my MPG sucks....

[BlueSky]

Gumout contains polyether-amine which is best cleaning ingredient. A bottle of Valvoline Complete Fuel System Cleaner which also contains polyether-amine finished cleaning the carbs on my ZN700 and really smoothed out the engine, a whole bottle in 3 1/2 gallons of gas, and now the Gumout appears to have done the same for my Venture.

[Patch]

As we started with mileage or the distance we can travel on a venture, which as Suzi learned in 85 is very important on a touring bikes; getting fare mileage means for one, keeping the bike in good mechanical condition, and using the correct fuel is also very important. If we run an octane designed to burn slower than our combustion design--- then we are wasting a portion of the stoichiometric ratio. If we need to run any conditioner on a regular bases, we are running out of tune! That is why I agree with GW and the old-school thinking.

Much of the spring disappointments we have with all our bikes is improper storage, which is when we need to condition the fuel to prevent the carbs, filter, pump, tank, lines..... from gumming up.

[BlueSky]

I run premium in my 89 because I can buy alcohol free premium at any of many of the local GoGas stations cheaper than I can buy alcohol free regular at the only other gas station that sells alcohol free gas in my area. The GoGas 87 octane has alcohol. I also use it in all of my yard tools and both cars we have which require premium.

[camos]

Again, to each their own although I disagree with a res position being "useless".

 

I've never owned or even seen a bike where the RES is separate from the main tank so that's pretty much moot.

 

Stuttering means pull over and switch to reserve. It's not like the bike just drops dead while riding.

 

Once I've switched to res, there is no question in my mind how much fuel is remaining in the tank and how long I've got.

 

I also use the trip to know when RES is going to hit and then when empty is going to happen. I fill before RES in normal running but if I get caught with my butt hanging out and have to use RES, I know beyond a shadow of a doubt I have "XX miles" left before I'm walking/pushing.

 

Just a different way of doing business.

 

Like I said, Free country...

 

The day before yesterday the fuel warning light came on about 5 km before I got home from work at about 120 miles (just a guess). Planned on stopping at my favourite gas station but managed to forget and flew by it in the wrong lane before it dawned on me. Figured there was enough gas left to get to get to work and back the next day so did not bother turning around. The next day I'm half way home when the tank ran dry at 144 miles. So, once again I was wrong, hope this is not going to become habitual. Did I tell you my memory is not all that good? Or else something is out of wack. It's also possible I've mixed up the numbers between the 90 with kilometres and the 89 with miles. The other possibility is over the winter I usually traveled at about 90 kph but with the great weather lately it's closer to 120 kph. What happened was no sputter but lost acceleration, likely dropped two cylinders. Was in the fast lane with heavy traffic all around and it was a bit dicey getting into the curb lane to pull over. Fortunately my separate reserve tank was in the right saddlebag, left over from my last day trip into the toolies.

 

Like you often say, "It's a free country" and all that but the reserve switch really is pointless if you know your ride and particularly so when the reserve area gets crudded up with old particles of whatever falls out of gas and whatever water manages to collect in there. Seems to me the better method is what we both already do, to monitor the trip gauge.

[Great White]

The day before yesterday the fuel warning light came on about 5 km before I got home from work at about 120 miles (just a guess). Planned on stopping at my favourite gas station but managed to forget and flew by it in the wrong lane before it dawned on me. Figured there was enough gas left to get to get to work and back the next day so did not bother turning around. The next day I'm half way home when the tank ran dry at 144 miles. So, once again I was wrong, hope this is not going to become habitual. Did I tell you my memory is not all that good? Or else something is out of wack. It's also possible I've mixed up the numbers between the 90 with kilometres and the 89 with miles. The other possibility is over the winter I usually traveled at about 90 kph but with the great weather lately it's closer to 120 kph. What happened was no sputter but lost acceleration, likely dropped two cylinders. Was in the fast lane with heavy traffic all around and it was a bit dicey getting into the curb lane to pull over. Fortunately my separate reserve tank was in the right saddlebag, left over from my last day trip into the toolies.

 

Like you often say, "It's a free country" and all that but the reserve switch really is pointless if you know your ride and particularly so when the reserve area gets crudded up with old particles of whatever falls out of gas and whatever water manages to collect in there. Seems to me the better method is what we both already do, to monitor the trip gauge.

 

We agree to disagree.

 

[camos]

I run premium in my 89 because I can buy alcohol free premium at any of many of the local GoGas stations cheaper than I can buy alcohol free regular at the only other gas station that sells alcohol free gas in my area. The GoGas 87 octane has alcohol. I also use it in all of my yard tools and both cars we have which require premium.

Not that I know anything much about anything at all but it seems to me that regular gas with alcohol probably works better in these old bike than premium gas without alcohol. Particularly if you ride regularly so water absorption does not become a major issue.

 

That's just my untested opinion which is likely not worth CA$.02 never mind US$.02.

[dna9656]

We agree to disagree.

 

 

The reserve is just a fuel outlet or feed inside the tank that is placed lower (relative to the MAIN outlet or feed) in the tank than the "MAIN' outlet or feed. So when the fuel level falls below MAIN feeder the lower (RESERVE) feeder then supplies the remainder of the fuel in the tank, There is no separate reserve tank. There is no crud in there because of it's not being tapped into and flushed out. IMHO using that main/reserve valve (because o it's age) is asking for a leak. The O ring(s) in there are OLD, the gaskets are just as old. I have rebuilt them "JUST BECAUSE" and regretted it. Mine is set to the RESERVE position and there it stays. Watch your distance traveled (be it Kilos or miles) asnd the gauge. Clean all the contacts in the ignition, make sure you have the proper Ign. spark plug wires, plugs are properly gapped. Check the compression, maybe you got a leaky valve or head gasket, maybe a spark plug is loose (happened to me) just make sure you don't over torque anything.

[Patch]

I run premium in my 89 because I can buy alcohol free premium at any of many of the local GoGas stations cheaper than I can buy alcohol free regular at the only other gas station that sells alcohol free gas in my area. The GoGas 87 octane has alcohol. I also use it in all of my yard tools and both cars we have which require premium.

 

I see the dilemma!

[Great White]

The reserve is just a fuel outlet or feed inside the tank that is placed lower (relative to the MAIN outlet or feed) in the tank than the "MAIN' outlet or feed. So when the fuel level falls below MAIN feeder the lower (RESERVE) feeder then supplies the remainder of the fuel in the tank, There is no separate reserve tank. There is no crud in there because of it's not being tapped into and flushed out. IMHO using that main/reserve valve (because o it's age) is asking for a leak. The O ring(s) in there are OLD, the gaskets are just as old. I have rebuilt them "JUST BECAUSE" and regretted it. Mine is set to the RESERVE position and there it stays. Watch your distance traveled (be it Kilos or miles) asnd the gauge. Clean all the contacts in the ignition, make sure you have the proper Ign. spark plug wires, plugs are properly gapped. Check the compression, maybe you got a leaky valve or head gasket, maybe a spark plug is loose (happened to me) just make sure you don't over torque anything.

 

No orings in the 86 petcock that I have. The insides are a plastic material that simply cycles openings, much like a rotary valve works. The only gasket/oring is on the cover or turning cover if you prefer.

 

Where did this concept of a "reserve tank" come from? Every motorcycle tank I've ever had is just one tank with a petcock that draws from two separate height standpipes. The stand pipes are either integrated in to one assembly or they are separate. The 86 petcock I have is no different in that it has two separate standpipes:

 

http://i1174.photobucket.com/albums/r618/justonepict/5337E2DF-03E6-42BC-8A85-9AB35EDA19CF_zpsz6bstgbh.jpg

 

http://i1174.photobucket.com/albums/r618/justonepict/EA341FD7-B0E5-4D91-AD61-327AECF86B95_zpsnu9mgkhk.jpg

.

 

I'm thinking maybe I should take a few pictures of the one I have to try and clear up some of the misconceptions that seem to be floating around here....(edit: added pictures)

 

In simple diagram terms, it works like this:

 

http://www.triumphrat.net/attachments/twins-technical-talk/38672d1310169148-are-there-two-different-fuel-tubes-petcock.jpg

 

The OEm's intent is for the owner to run in the "on" and switch to "res" when the engine stutters. That way you know without doubt you have "X" amount of fuel in the tank and better start looking for a fill asap.

 

First hit on google:

 

http://i102.photobucket.com/albums/m120/Terp84Alum/Bike/02XL1200cPetcock.png

 

At any rate, I'm not trying to tell anyone how to run their petcock (is it just me or does that sound wrong? ). But know that it is intended to be used a certain way, that's why it's built the way it is. If someone want to run the tank to dry and switch to the "black caddilacs" for transport, no skin off my bee-hind.

 

 

Personally, I use the res position on all my bikes. It's not the way I know if I need fuel, it a way of the bike telling me there is only "X" amount of feul left and you better act accordingly. When its necessary to switch to res, the amount of fuel in the tank is a known quantity because it is a function of the height of the stand pipes. Nothing more, nothing less.

 

To me, that's valuable information as I know I can get a high of "X" mileage and a low of "X" mileage depending on how I ride. That means I can know if I'm going to make the next station or if I have to get out my phone and CAA membership card.

 

Just a different way of doing business. Being a SAR helicopter operator, perhaps I'm somewhat more focused on fuel than most. For me, fuel is life. I want to know just what I have in the tank and exactly what I have to do about it.

 

Everyone is free to do as they wish.

 

I'll use the res position thanks.

 

 

Anyways, this thread has gone off so high and right I no longer have any interest in it. Carry on as y'all see fit!

 

Edited May 23, 2015 by Great White

[dna9656]

Not that I know anything much about anything at all but it seems to me that regular gas with alcohol probably works better in these old bike than premium gas without alcohol. Particularly if you ride regularly so water absorption does not become a major issue.

 

That's just my untested opinion which is likely not worth CA$.02 never mind US$.02.

 

Octane is a additive that increases the flash point of the gasoline. Premium gas does not have more energy in it than regular gas. Engines requiring premium gas have higher compression ratios than those that have 8.5 to 9.5 compression ratios. Increased compression is where the extra power comes from.... NOT the gas it self. Were it NOT for octane we'd have pre-ignition (engine knock) from hell in "high" compression engines.

[BlueSky]

I think the problem is when the bike sits a long time with gasoline that has 10% ethanol. As long as you ride often, probably no detrimental effects.

 

And thanks for all the diagrams Great White. Only comment is about the fuel petcock is that up is Reserve and down is ON.

[dna9656]

Aww; Geeze! He's got dirt under his fingernails!!!! He's no "Sir!" I bet his parents were married PRIOR to his conception...He's just a regular person (rem. to be pol. corr.) even IF he doanlike "MECHANIC IN A CAN!!!

 

All kidding aside; I get yer point, but I just gas up when she's half down. So I buy gas every other day. There is NO feelin' LIKE the feelin' o being in B-F-E (NONE of YOU should have to ask where THAT place is) and LOW on GAS.... no not THAT kind ... The OTHER kind....) at night, in the cold rain and your cell is dead...

It's night, you have a 1/2 a tank of gas, a pack of cigarettes and you're wearing sun glasses...Hit it.

[Flyinfool]

Aww; Geeze! He's got dirt under his fingernails!!!! He's no "Sir!" I bet his parents were married PRIOR to his conception...He's just a regular person (rem. to be pol. corr.) even IF he doanlike "MECHANIC IN A CAN!!!

 

All kidding aside; I get yer point, but I just gas up when she's half down. So I buy gas every other day. There is NO feelin' LIKE the feelin' o being in B-F-E (NONE of YOU should have to ask where THAT place is) and LOW on GAS.... no not THAT kind ... The OTHER kind....) at night, in the cold rain and your cell is dead...

It's night, you have a 1/2 a tank of gas, a pack of cigarettes and you're wearing sun glasses...Hit it.

 

And then you to can drive off the end of a bridge in Milwaukee that is headed north and land in Chicago.

[Patch]

I did a mileage check yesterday, also did some conversions:

 

Here's my base line: compress 170 x 4

NO vacuum leaks

all 4 are as equal a tune as I can do

 

188 KLM took 12.05 LT

6.38 LT per 100 KLM conversion: 62 miles / 100 KLM takes 1.68 gallons U.S. if you divide that then the ans is 36.9 miles to a gal.

 

I would expect to see 38/40 if I ran a long trip east of the Foothills.

 

Regarding octane, I think we are on the same page. Higher octane use won't serve us well on these bikes, the burn will be too slow, which means we can't extract the energy potential. For those that don't quite understand this here is a simple explanation: compression causes heat, (it also causes spring like pressure)squeezing a stoichi mix (bare in mind the back pressure from the last cycle cooling effect) now add in the BTDC say 8* then ignition, the combustion starts while the piston is still moving up to TDC, and this helps to mix the stoichi and the planned flame shape that is extracting the heat or BTUs from the (mix) stoichi! This process causes the expansion pressure exerted on the piston in a downward motion! The burn time is critical!

 

Now the above is a simple explanation at low RPM. But add more ignition advance- I think these are up to 40*ish BTDC for high rpms

which happens in order to allow enough time to complete the burn cycle during a compression stroke, think about it, it's not a puzzle everyone enjoys I get that!

 

One more thing to add into the mix, liquid cooled will be more resistant to moving up in octane, when other ratios have not been changed, unlike air cooled engines which run much hotter.

 

Patch

[dna9656]

I've read that all gasoline is the same when it leaves the refineries and enters the National Gasoline Pipe Line System. What makes the difference(s) in brand name fuels are the chemical compounds (additives) added at the local terminus. I am not familiar with how that works... I'm sure some one here can explain all that. Point is we all use fuel additives put in the fuel by the distributors; be they Octane, Alcohol, Boron (Standard Oil), Cleaners, (Chevron is big on their cleaning additive). Here in the NW Fred Myer (a retailer) gas has a HUGE campaign to get customers to add cleaners to the gas at the pump. Sun Oil Company (Sunoco) used to have several grades available at their "Custom Blend Pump" At Sunoco you could get gas that was so hot that sodium filled valves (the valve stems) were recommended. Who remembers "Sunoco 260"? So far as I know MOST gasoline sellers have a super duper cleaning additive that will return your engine to "like new" performance.

I think my source for this gas additive debate is the Book "Drive it Forever" by by Robert Sikorsky and George A. Hague. there IS some out dated info in it. Like the Slick 50 recommendation. (I use it with good results.... anyway) and some other things. In the book you will find lots of knowledge that is reliable and some that isn't just like any other how to book. I will say now that my copy was loaned out and never returned so I don't have it on hand to CONFIRM what I said about gasoline, I read the book back in the 80s. I'm sure it has been edited since then. http://www.amazon.com/Drive-Forever-Secrets-Long-Automobile/dp/0965757706/ref=sr_1_1?ie=UTF8&qid=1432488851&sr=8-1&keywords=Drive+it+forever

[Patch]

Doug, often times when combustion tweaking is shared we see it only to be dismissed by wives'tails.

Octane is Octane, it is not a detergent, it is labeled as a rating, sometimes we see it as - Regular- Mid grade- Premium/Super..... 85 to 100+, detergents added to fuels are to deal with the "before and/or after" combustion; unlike Octane which has a direct effect on combustion!

 

"So far as I know MOST gasoline sellers have a super duper cleaning additive that will return your engine to "like new" performance."

 

Surely you don't believe that marketing hype?

[dna9656]

No I do not believe the hype that's why I use dthe term :"super duper" and quoted "Like New" a term often used in advertising verbiage.

 

According to the Federal gov't (see http://www.consumer.ftc.gov/articles/0210-paying-premium-high-octane-gasoline)

 

and I quote: About Octane Ratings

 

What are octane ratings?

 

Octane ratings measure a gasoline's ability to resist engine knock — a rattling or pinging sound that results from premature ignition of the compressed fuel-air mixture in one or more cylinders. Most gas stations offer three octane grades: regular (usually 87 octane), mid-grade (usually 89 octane), and premium (usually 92 or 93). The ratings are posted on bright yellow stickers on each gas pump.

 

Now according to wikipedia Octane is a chemical not a rating. The amount of octane in gas is rated but the term "octane is not a rating. See https://en.wikipedia.org/wiki/Octane or more info.

 

Quote: Octane is a hydrocarbon and an alkane with the chemical formula C8H18, and the condensed structural formula CH3(CH2)6CH3. Octane has many structural isomers that differ by the amount and location of branching in the carbon chain. One of these isomers, 2,2,4-trimethylpentane (isooctane) is used as one of the standard values in the octane rating scale.

 

Octane is a component of gasoline (petrol). As with all low molecular weight hydrocarbons, octane is volatile and very flammable.

 

Use of the term in gasoline

 

"Octane" is colloquially used as a short form of "octane rating" (an index of a fuel's ability to resist engine knock at high compression ratios, which is a characteristic of octane's branched-chain isomers, especially isooctane), particularly in the expression "high octane." However, components of gasoline other than isomers of octane can also contribute to a high octane rating, while some isomers of octane can lower it, and n-octane itself has a negative octane rating.[3]

Metaphorical use

 

Octane became well known in American popular culture in the mid- and late 1960s, when gasoline companies boasted of "high octane" levels in their gasoline advertisements.

 

These commercials disappeared by the time of the 1973 Oil Crisis, which spared gasoline companies the need to compete in advertising. "Octane" was rarely cited in non-technical contexts over the next two decades.

 

The compound adjective "high-octane" is recorded in a figurative sense from 1944.[4] By the mid-1990s, the phrase was commonly being used as an intensifier and has found a place in modern English vernacular.

 

"Octane" is a slang term for trihexyphenidyl, because of its similarity to its trade name Artane.

 

According to Wikipedia.

 

More IAW Uncle Sam

 

http://mn.gov/commerce/weights-and-measures/images/OctaneFacts.pdf

 

Doug, often times when combustion tweaking is shared we see it only to be dismissed by wives'tails.

Octane is Octane, it is not a detergent, it is labeled as a rating, sometimes we see it as - Regular- Mid grade- Premium/Super..... 85 to 100+, detergents added to fuels are to deal with the "before and/or after" combustion; unlike Octane which has a direct effect on combustion!

 

"So far as I know MOST gasoline sellers have a super duper cleaning additive that will return your engine to "like new" performance."

 

Surely you don't believe that marketing hype?

[videoarizona]

This weekend, lady and i went for a breakfast ride to Wickenburg... 44.1 mpg for 137 miles. 05 2nd gen. Took our time. Regular gas... No additives past two tanks. Getting better mpgs each tank. 65/70 mph with some 50 on two lanes. No wind.

[mralex714]

The day before yesterday the fuel warning light came on about 5 km before I got home from work at about 120 miles (just a guess). Planned on stopping at my favourite gas station but managed to forget and flew by it in the wrong lane before it dawned on me. Figured there was enough gas left to get to get to work and back the next day so did not bother turning around. The next day I'm half way home when the tank ran dry at 144 miles.

 

If those are US miles you are getting less than 30 MPG. Check your rear brake caliper. Sometimes the pads wear a groove in the caliper and the pads get hung up on them and drag. If this is happening the pads will be worn uneven.

[camos]

If those are US miles you are getting less than 30 MPG. Check your rear brake caliper. Sometimes the pads wear a groove in the caliper and the pads get hung up on them and drag. If this is happening the pads will be worn uneven.

Yes they are US miles and I do think I was getting better mileage on a tank before so I had better check to see what's up.

Thanks for the heads up.

[tankerman]

I'm averaging about 35MPV on my 2011, sometimes I can get it up to the low forties in steady state cruising with the cruise control. Just wondering how the jibes with the rest of you folks.

[tlm]

I get right at 30MPG on my '02 RSMV. Sometimes a little lower, sometimes a little better.

[Patch]

No I do not believe the hype that's why I use dthe term :"super duper" and quoted "Like New" a term often used in advertising verbiage.

 

Sorry Man, tripped over my French!

 

Patch

[dna9656]

Dats OK!

[Great White]

To bring my part of this thread full circle; I was right when I said my mpg sucked.

 

To explain:

 

The bike started missing the other day. Get home and discover that two of the 4 throttle slide diaphrams had seperated from the slides. I pulled all the diphram covers off and discovered the 2 had seperated completely, the other two were in place but the backing rings were loose.

 

I was somewhat amazed the bike ran at all but it was being a real trooper and ran fairly smooth until it just couldn't fight the good fight anymore.

 

I reseated all the diaphrams and took it for a ride. Smooth power everywhere again. In retrospect, that's likely why it was so hard for me to make smooth throttle transitions form on and off throttle. No progression on the slides. Likely lagging or jumping postions and just generally wreaking havoc on the needle postion.

 

And now, a few days out, I'm at 65 KMS on the clock and the fuel gauge is just beginning to flicker between full and the next lowest bar (mostly staying on the full bar). Before, I was down around 1/2 tank or less at about 80 kms on the clock.

 

So, I'm going to say (tentatively) problem found and yes indeed; my mpg did suck!

 

And I will be adding an item to my annual maintenance check list: remove carburetor diaphram covers and confirm throttle slide sealing rings are seated.

 

Edited May 27, 2015 by Great White