I have been reading that higher octane actually isnt better, especially for older bikes. I have been driving with premium thinking I was doing something good.
Is this correct? That lower octane is actually better for older bikes, and that higher octane could be causing my issues with stalling? http://www.magnaownersoftexas.com/forums/index.php?topic=4339.0 (http://www.magnaownersoftexas.com/forums/index.php?topic=4339.0) (see this topic for the stalling issues)
Unless you're getting symptoms of pre ignition like pinging from detonation then use the regular 87 octane as suggested by the oem engineers. I guess there are places in this country where the regular is actually marked 85 on the pumps so use the 87 octane or higher in places like that. The higher octane is more resistant to detonation, it doesn't burn slower as is a common belief. Paying for a higher octane than you need is a waste of money. I know what the commercials say but it does not give you any more power than regular. Octane has nothing to do with your stalling and the octane level is dictated by the engine design not the year the engine had been made.
I run regular here in Portland, OR where it doesn't get hot much. When the temps are very high like 85-90 or more degrees I switch to the mid octane gas which is 89 octane. This is a necessity at least on my bike because when it gets real hot I do hear some pinging if I give her a lot of gas or am going up a hill. Any detonation is bad and can damage or ruin an engine. Hope this helps.
Generally speaking, the lowest octane which does not cause pinging will give the best performance, for just about any engine. For our Magnas, 87 octane is fine. Anything higher just empties your wallet faster, but won't make the bike run any faster or better.
I concur with all the comments above -- my experience right here in Austin, TX is the same as theirs. I used the mid grade for a bit until I learned from these guys that it was not necessary. Both my '96 Magnas run great on the lowest grade, with no pinging at all.
Of course, both have aftermarket pipes, K&N filters, and rejetted carbs, but stock should also run fine on "regular".
Although I understand and agree in general with the statements above, Speaking as a '94 owner.. There is a sticker on the frame that states 89 Octane on the '94.
When I run Regular(87), I get pinging, so I run 89.. IF you can run 87 and it doesn't ping, then go for it, but as I said, I have to use 89. I have not checked since I re-jetted, but that really shouldn't have anything to do with the combustion chamber and pre-ignition.
I used to buy into the idea that I was doing my vehicle's engine a favor by running premium: after all, if it runs better when you do so, it must be better for it, right? Hoot, Lawrence, and some others finally managed to educate me, and I am now convinced that unless you have an engine designed for very high compression, if it runs better on premium, that is a symptom that it needs adjustment or repairs. Maybe cleaning and/or synchronizing the carburetors is in order.
Since then I have been told that running premium on a long-term basis can cause deposits to form on the piston and combustion chamber faces and that such deposits (being carbon) are extremely hard and very diificult to remove.
I used premium for a few years (6) until I switched to the 89 octane. My bike is a 2000. But I put a smidgen ( 3-4 table spoon) of carb cleaner or injection cleaner in every other fill-up. The carbs have never been adjusted or tampered with (bone stock), I have a K&N filter, and I've drilled holes in my baffles (the small round tube attached to the end plate in the exhausts) to increase exhaust sound. There is no popping on deceleration (I use the engine for breaking quite often), and yes, there is a slight flat spot around 3500 - 4000 RPM, but I'm never in that zone very often.
All-in-all, if it ain't broke, don't fix it. My bike has 61,000 Km on it, or 38,125 miles on it.
I check the valves every year, and some are out by 2 thou. Guess I'll have to get them done eventually, but I must find a competent mechanic first, which will probably be a bigger job than doing the valves! lol
Cheers!
Greg
Quote from: magnagregcan on May 23, 2010, 03:59:53 AMI check the valves every year, and some are out by 2 thou. Guess I'll have to get them done eventually, but I must find a competent mechanic first, which will probably be a bigger job than doing the valves!
Do tell. (http://s5.tinypic.com/2it2dtz_th.jpg)