What type of gas...

So will running 93-94 when it's not required. May not be measurable by the seat of your pants, but thermodynamics favor the fastest "burn" you can get without detonation. This must be balanced with the cylinder, piston, head, and valves being able to cope with that heat. Manufacturers nowadays spend 30-35 million to put a clean sheet motor design on the market. If it is stock, or within about 10 percent, it should be reliable and durable with the reccomended fuel

$0.02.
 
I would take ANY non-ethanol fuel, yes. Unfortunately in the Dallas-Ft. Worth area, all is 10%, and most of the surrounding areas have gone to it too, as the refineries sell it to them cheaper so they can run more of it between refinery turn-over to the next fuel type.
 
I've studied detonation for years. As example, I use a home made water injection system in the car I supercharged to squash detonation. Our XS will run on anything but every year about one in 1000 old bikes will hole a piston on the highway. These aren't just XS650s, they are Brit bikes and Hondas. The rider fills up with low octane 87 like he always does. It will be hot. The bike will be moving fast keeping up with traffic. Maybe the road will incline or a headwind will come up, something that puts even a greater load on the engine. Detonation may start and the rider will not hear it. It may get stronger and seem like valve noise then, POW! Smoke and lost power, tears and lost money. Old bikes use old tech which gives no protection. 91 to 93 octane costs 20 cents more and is the best defense against detonation. Cheap insurance me thinks.

Rlauchard, your '81 has a better chance of detonation survival because of the electronic advance. This gives a slower advance than mechanical and is less likely to over advance the timing.

It is a myth that high octane burns slower than low octane.

Tom
 
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I cant seem to find any ethanol-free fuel here in South Bend, IN... wonder if it has anything to do with the Ethanol Plant about 1.5 miles from my front door?

I have been reading a few things that say that Ethanol actually does not agree with 30+ year old fuel systems. especially floats and tanks

Here in central OH, I have found that Krogers (supermarket) gas stations use pure gas. At least there is no indication on the pump that states, this fuel may contain up to 10% ethenal. :shrug:
 
Thanks all, Belle....what compression is the 81 xs650 SH...do you know? I'm in Columbus, OH...looks like there are no Ethanol free stations near me...

Check out the gas at Krogers/Turkey Hill stations. Their fuel pumps have no warning that the fuel may contain up to 10% ethanol. I believe this is a law in OH, that this warning sticker has to be on the pump. Im wondering how bad this dilluted gas will be in my just restored 1959 Evinrude Outboard Motor. Mitch :thumbsup:
 
Also, E85 is 85% gas & 15% ethanol--it can be bad for your engine & parts--you should learn about it; we, as a society, are likely to end up there...somewhere...anyway

Actually E85 is 85% ethanol and 15% gas. E10 is the new "standard" 10% ethanol crap they give us these days.

Another thing to keep in mind if running anything other than 87 is if the station has a single hose or separate hoses for different grades. If it's a single hose since most people buy 87 you are getting about a half gallon of 87 (if not more depending on the design of the pump) before the high test stuff comes out. Not really an issue for cars, but for bikes and especially guys like me with the ultra long range Lowbrow P-nut tank carrying a whopping 2 gallons on a cold day, this can be a problem. Some single hose stations show what type of gas was last purchased, but I've only seen this a few times.
Truth be told, I've been running 87 E10 for a while now, but I think I'm gonna go back to 93 E10 from 3 hose stations for a while to see if I can tell a difference. It runs fine, but after sitting at a stoplight for a while it starts to idle erratically sometimes. If it's an air leak I've yet to find it, and I seriously doubt my new JBM carb holders are the cause.
 
What's that tuner stack in your avatar? Looks like older Cessna Citation gear. I'm pretty spoiled to 3, 4 , and 5 tube systems nowadays. Garmin G-1000 is quite the integrated setup.
 
What's that tuner stack in your avatar? Looks like older Cessna Citation gear. I'm pretty spoiled to 3, 4 , and 5 tube systems nowadays. Garmin G-1000 is quite the integrated setup.

It's a transponder. Not sure what from exactly, I just searched for something tuned to VFR (1200). I hear you with the newer setups. I did a bit of my training with the G-1000 and I still haven't figured out everything it can do yet lol. My school has a few PA-28R-180 Arrows from the early sixties with probably the original avionics in them. If you're lucky one of the radios will work. One of them even has a Loran. It turns on, but all it really does it get nearly hot enough to burn you. What type of flying do you do?
 
Don't fly. Currently, I'm in Auburn, Maine, working on a restoration of a Lockheed Super Constellation. It's a 1649A that used to belong to TWA. Lufthansa is doing the project. I'm a team leader. We have the horizontal and vertical tail structures.

The 1649 is the last model, the big boy. It has a 150 foot wingspan. All previous models were 120. I came up here because I could not pass up the money, and the Repair Station I had worked at for 12 years was not growing the way I had imagined. Stayed there about 3 years longer than I should have. around 20 years of corporate jets prior to that, mostly Citations, but we worked Lear, King air and more recently Embraer Phenom 100 and 300 jets. I loved the work, but management kept trying to expand into different makes without the training and tooling to support the work force, then got all irritated when we could not deliver on time or on budget. Go figure. I thought we were going to focus on the core business and do it well, which we did for a while, but it kept creeping into aircraft that are much harder to support and more labor intensive. Hopefully when I get out of here, something solid will be available in the Dallas market.
As far as older small planes, I've worked them too. You are probably aware that NARCO is an acronym for Not A Real Company!
I've worked Collins, Garmin, Honeywell, and Universal integrated systems, and Garmin just has it nailed. Great compatability, solid, reliable products, and functions galore. I can't profess to know even half of what a G1000 will do across the board, but synthetic vision technology that works ALL the time is an incredible tool for owner operators in single pilot aircraft. I guess the more you use it, the better you get with it. Those old Arrows are solid little airplanes.
 
Wow that's a nice gig, the Super Connie is nothing short of beautiful. My uncle was a radio operator on those in the Navy back in the day. I used to work for Gulfstream as an A&P when I got out of the Air Force (F-15 crew chief). I'm not gonna lie, I really miss banging wrenches on them sometimes. And yes the Arrow is a solid plane, but it's got the power-off glide ratio of a hate note tied to a brick...
 
They don't call that wing the "Hershey Bar" for nothing! I don't think that airfoil is even in tne N.A.C.A. standards catalog!

As for the 1649, awesome old beast. a transitional point in construction technology. They only made 45 of these and only 44 were sold. They tried to put the C-130's original engines on the other one, but the 707 killed all that. There are only 4 of them left. 2 are here, one in Florida, and the other one is in South Africa, on a stick. I mean on static display!

There are many flying 749's, 849's, and 1049's. This will be the ONLY 1649 flyable and complete on the earth.
 
I have an almost bone stock 81. The only thing changed is the stock air filters turned to dust. I rebuilt them with one layer of foam. No carb work. Still has the plugs in over the air mix screws.
I normally run 93 gas. federal law states all motor fuel sold have ethanol in it. The same law says that the pumps need a label saying it can have up to 10% ethanol.
The only gas you can buy with out ethanol is airplane fuel and marine fuel. I just don't like the extra cost of getting it from the airport, need an airplane to get fuel, or at the Marina. Usually twice the price.
Any way after reading about this octane vs pinging I did two fillups on the bike with 89 octane fuel. Pings a lot with the lower octane fuel. This proves my point, use the highest octane fuel you can find.
Leo
 
I did two fillups on the bike with 89 octane fuel. Pings a lot with the lower octane fuel. This proves my point, use the highest octane fuel you can find.
Leo

I and others use 87 all the time, with no pinging. I have 23,000 miles using 87 octane on my xs650.

The bike needs to be tuned to benefit from whatever gas you use. If your timing is too advanced for 87 it will ping. Retard the timing. If you tend to lug the engine it will ping sooner with 87. Don't lug the engine. If you are running lean it will ping easier with 87. Don't run lean.
 
As I said it is an all stock 81. The timing is set with the TCI. It runs well with good fuel and gets around 55 mpg. Can't complain.
Leo
 
^Mine's a bone stock '81 too. I used xsjohn's pickup slot method to retard the timing as far as it would go and still be in the marked good range. My backup pickup was slotted at the factory; later year I think.
 
My understanding is that "octane" is simply resistence to ignition. If your gas doesn't have enough your fuel-air won't wait for the spark plug's prompt to start dancing. "ping" bb's on a tin roof (melting pistons on the grill) If you have enough, the fuel-air will need the spark plug's invitation and paying for more is a waste of money.

So, "Your bike will tell you what it needs" translates into "run the lowest octane that does not ping."

Of course if it's 100 miles uphill to to BFE, 120 degrees in the shade - and there ain't any - and the brand on the pump is unknown to you .. well maybe it's not a bad idea to buy more flame retardant than you might actually need.
 
I normally run 93 gas. federal law states all motor fuel sold have ethanol in it. The same law says that the pumps need a label saying it can have up to 10% ethanol.

Leo

Yes,and no. There is more to it than that.

You can buy non ethanol but it is getting harder and harder to find. I only buy non ethanol premium for my snowmobiles in the Northwood's of Wisconsin. Read here:

http://e0pc.com/
 
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