MMO is a wonderfull upper cyl lube, but being mainly kerosene, it will slightly drop the octain .
Ron

 

that would not work (drop in Octane). Will check some of the others or may have to stick with HD's additive as much as I would hate to.

 

Wow. A lot of misconceptions going through this thread.

>> Formulated with Duralt Fuel Compound which permits the use of lower octane fuels. Reduces octane requirement increase that normally occurs with mileage. Controls the formation of combustion deposits. <<

This does not claim to increase the octane of your fuel. Carbon build up in the combustion chamber creates hot spots, which can cause detonation. When that happens, you start needing higher octane fuel to prevent it. This stuff claims to inhibit the carbon deposits.

>> If your bike is stock compression, it's only 8.5:1. Using higher octane is of no benefit whatsoever, and might actually make your bike run worse. <<

Yes, and no. There is no benifit at all to using higher octane than you actually need. Will it run worse? I doubt it. Tests have shown that to degrade performance in a stock engine you have to get the octane pretty high, well over 100.

>> I am a firm beleiver in Lubricating the upperon my bike, I know how quite my oldbike is... <<

Not related. It only lubricates the parts touched by raw fuel. That's the upper part of the cylinder itself, where the rings contact the cylinder walls. That's a pretty quiet area to begin with. The parts that generally make noise are the valve train, which is not touched by raw fuel. Your quiet old bike is evidence of quality oil and a good maint program.

>> I'm at 39,000 miles with to problems and had no motor work done, no noise and uses no oil at all. <<

If you were talking about your Ford or Dodge engine, would you say the same thing? 39K is pretty low mileage. If you're having engine problems at that point, you're doing something wrong. It's certainly not proof that a fuel additive is doing it's job. Again, proof of quality oil and a good maint program.

IMO, fuel additives are not needed with every tank. It's a waste of money, and provides no proven benifit. Like oil additives, it's snake oil. But, it's your money and your bike. I can't see that it would hurt anything. You should do whatever helps you sleep at night.

 

Guess you need to contact HD and tell them they are full of BS on their fuel additive statement.

Yep, I'll do what makes me feel good and yep, I keep it maintained with all oils changed at less than 3000 miles(anbout every 3rd month) with high quality oil's, and cleaned spark plus cause it makes me feel good to know I am doing my part to keep her runnig for many more years.

 

Yeah, like that would do any good

 

Vehicles with high-compressioin engines, or knock sensors, benefit from higher octane fuels, period. There is a limit at which high octane ratings no longer improve performance, of course. But raising the octane rating in fuel enhances performancebecause the timing isn't retarded by the knock sensor to prevent the detonation. BTW, Marvel Mystery Oil is a solution whose lubricity increases at high heat. While most oils lose lubricity when they are heated, one of the "Marvels" about this additive is that it gains lubricity when heated, and the solvent additives in it will dissolve top-end varnish in engines with periodic use. Good stuff, and not snake oil. I could never recommend snake oil to anybody, anytime. What kind of a chemist would that make me? [:'(]

 

Well, just gassed up with my second tank of 87%. did not noticve any strange nosie or pinging. The milage did drop some where around 1 to 2 miles per gal. Will know better after this tank.

 

Lots of good points and info here. One thing to remember is that gas honestly sucks today. The quality and consistancy of fuel is very poor, and judging mileage per tank doesn't really prove anything. I know Fordrecommends 4 tanks of fuel before any change can be verified, i.e. if you got a bad tank of gas. I'd say on a bike your mileage could vary easily by 2 or 3 depending on the quality of the gas at the station you used.

As far as that stuff cleaning the upper engine, well, I saw honest proof today that it worked in a 5.43-valve Ford V8 with sticking valves. The problem all started with crappy fuel in the tank.

The comment above about making you feel good is about right. You have to feel like you're doing the best you can for your engine. Some of it works, but I wouldn't over do it, because that stuff very well could cause problems elsewhere, maybe fuel lines, injectors, who knows.

Another thing to think about..... With the price of fuel, how long do you think that high octane sits in the tanks at the station compared to the 87?

 

Don't have to worry about injectors on this bike unless Santa comes tonight and sticks a new motor in with fuel injection.
Good point on the high test will sit in the tank's a lot longer than regular.