| Author | Message | ||
     Sanchez |
Many of the gas stations around here have no premium fuel, so I decided to try some 87 in the Uly. I had a pinging problem from the factory, so I retarded my timing to fix it quite some time ago. In theory it should run fine on lower octane, but I've never had the motivation to try it before now. I had about a gallon of 93 in it, and I added a gallon of 87. So far so good. No pinging even under hard acceleration. We'll see how it does once this tank's run dry, and I get some undiluted 87 in it. | ||
| Johnboy777 |
""I retarded my timing to fix it quite some time ago""} Just curious, how far did you retard it - static or via ECMspy...thanks. John. | ||
| Sanchez |
It was static. I think I only took one degree out, but I don't know exactly how many degrees each of the tick marks represents. Here's the thread with pictures: http://www.badweatherbikers.com/buell/messages/142 838/315389.html?1194111437 | ||
| Tocramed |
Hi Sanchez, I read your other thread. Awesome, this has helped greatly. But, after retarding the timing 2-3 degrees, it still pings in 3rd gear at high speeds under heavy acceleration (only a couple times in 20 mins of hard riding); can't get it to happen in 2nd anymore. So, how much is too much? Should I try retarding further? When you did this, did you have to reset your TPS and/or adjust your idle? | ||
| Hootis29 |
I run a lot of 87, and 89, with no problems, sometimes I even get better mileage. | ||
| Teeps |
When I tried retarding the timing there were 2 obvious and 2 perceived differences noticed. 1. engine idled slower, idle had to be raised. 2. engine did not ping. 3. acceleration performance suffered. 4. engine "seemed" to run hotter. (based on how soon the fan came on and whether it stayed on for the duration of the ride.) I have since returned the timing to the factory spec. | ||
| Skyclad |
I have not ever used 87, but my 08 handled a tank of 89 just fine when I had to do it. I put 4.1 gallons in, so there was not much premium left to bump up from 89. No pinging or noticed loss of performance. | ||
| Curly |
I'm having to do the same here in WNC and was wondering if Buell recommends 91 octane to cut down on the pinging or will running a lower octane actually do some harm? Someone in the know chime in. | ||
| Jlnance |
I ran 87 once in Death Valley, as that was all the station sold. It pings. I run 89 all the time in my 06, and it works just fine. I too think the gas mileage is better than with 93 octane, though that's just a seat of the pants observation. | ||
| Atoms |
I always use 89 in my '07, and crappy midwestern cornfed 89 at that - unless I'm on the road and don't have the option. Isn't that what the manual suggests? (not the crappy cornfed part...) | ||
| Froggy |
I would have to look it up again but I believe it states premium, which is 91 octane. I usually run 93. I ran 87 once on my Uly to see how it likes it. As long as i didn't go past 50% throttle or let the engine get bogged down I was fine! Pinged like a mofo otherwise.  | ||
| Hootis29 |
Not sure how you guys can hear all this pinging, with the fan, pipes ect.. Although I'm always wearing earplugs, and llistening to the radio so ? Mine may be pinging since day one, who knows, but its got 35 K + on it and still runs fine.... | ||
| Miamiuly |
As I understand it, a higer octane just resists pre-ignition. (detonation.) http://en.wikipedia.org/wiki/Octane_rating I'm not sure how high the compression is in this motor but maybe the engine heat also has something to do with premium being recommended. Like in the 70's early 80's when you would shut a car off and it would keep running (knocking) on detonation. Sometimes you had to make them stop by "flooding" them with throttle or re-start and shut down. (Message edited by miamiuly on September 25, 2008) | ||
| Davo |
Sanchez, Each of the large tick marks on the baseplate account for 10 degrees at the crank. The intermediate marks indicate 5 degrees at the crank. Each millimeter of movement measured at the far outside of the baseplate account for 3 degrees at the crank. | ||
| Natexlh1000 |
I will sometimes run 89 in my 2008. It pings a bit if I lean on it but it goes pretty much ok. It's odd but my fuel economy gets a little bit better too. Less Ethanol in 89? | ||
| Hootis29 |
remember when the manufacture recommends octane, they are covering there asses. i.e. Riding in excessive heat, two-up ect.. They want to make sure the bike NEVER pings. Most of our riding does not fall into this catagory. I ride all the time in the fall and spring, and never have an issue with 87. The better mileage comes from burning the fuel more completely with lower octane, thus more power and better mileage. | ||
| Sanchez |
> The intermediate marks indicate 5 degrees at the crank. Ahh, thanks! In that case, I took out 5 degrees. I didn't notice any change in idle or loss of power. It may have lost something on the dyno, but I can't feel it. OTOH, it may have been advanced so far that I was losing power that way instead, and now I'm just losing the same power due to too little timing. | ||
| Thunderbox |
Retarding your timing will make the engine run hotter. The reason for that is as follows. The air fuel mixture in an engine burns at a certain speed. It doesn't matter how fast the engine is spinning the fuel burns at the same speed. Retarding the timing will mean the fuel will burn longer in relation to piston travel than when it was advanced. This subjects the cylinder to burning fuel further down the cylinder and will cause an increase in the temperature of the cylinder wall. How much depends on how much you retarded your timing. Will it have an adverse effect on the engine? Who knows for sure other than Buell. This is where an oil temperature gauge is very useful. In answer to the higher octane only being there for preignition that is not entirely correct. Higher octanes primary purpose is not preignition but the prevention of detonation which is a different thing altogether. This is even more important in a larger volumn cylinder like the XB12 series. Small volumn cylinders like on a 4 cylinder 600cc don't have anywhere near the detonation problems of the bigger cylinders and can quite nicely get along on regular fuel. | ||
| Miamiuly |
Both forms of auto ignition. Detonation occurs when excessive heat and pressure in the combustion chamber cause the air/fuel mixture to autoignite. Another condition that is sometimes confused with detonation is "preignition." This occurs when a point within the combustion chamber becomes so hot that it becomes a source of ignition and causes the fuel to ignite before the spark plug fires. This, in turn, may contribute to or cause a detonation problem. http://www.misterfixit.com/deton.htm | ||
| Teeps |
Thunderbox Posted on Friday, September 26, 2008 In answer to the higher octane only being there for preignition that is not entirely correct. Higher octanes primary purpose is not preignition but the prevention of detonation which is a different thing altogether. This is even more important in a larger volumn cylinder like the XB12 series. Small volumn cylinders like on a 4 cylinder 600cc don't have anywhere near the detonation problems of the bigger cylinders and can quite nicely get along on regular fuel. If the above ( in red ) is true, can you explain why my 1300cc big twin Honda VTX didn't ping under any circumstance, on 87 fuel? | ||
| Froggy |
Teeps my guess off hand is that it auto retarded the timing, like most cars that require premium. | ||
| Teeps |
Froggy, The VTX does not have a knock sensor. | ||
| Glenn |
The compression ratio may be low enough that premium isn't required. | ||
| Teeps |
Glenn, It's 9.2:1, higher than I though. | ||
| Thunderbox |
The compression is a lot lower than the Uly. Secondly I would guess the timing is a lot more retarded than the Uly is and that is not as much of a problem with a liquid cooled engine. With liquid cooling you can control the heat a lot better | ||
| Natexlh1000 |
I think those Hondas are dual plugged too. | ||
| Teeps |
The VTX only makes 58 rear wheel hp, it is water cooled and yes does have two plugs per cylinder. The change from that bike to the Uly was dramatic, like going from night to day. | ||
| Bosh |
"The VTX only makes 58 rear wheel hp, it is water cooled and yes does have two plugs per cylinder. "  The Honda VTX makes 107hp and 120 ft/lbs torque. edit: VTX 1800, but I doubt the 1300 is THAT much lower. (Message edited by bosh on October 01, 2008) | ||
| Edgydrifter |
There's also the VTX-750, for which 58hp sounds about right. | ||
| Teeps |
Bosh, Most VTX 1300s have a whopping 58 "rear wheel" hp. Many 1300 riders have had their bikes dynoed and they run between 58 and 60 in stock form. The 1800, on the other hand might have 107 hp at the crank shaft or, more likely at the wrist pin. Just as our Buells have 103 hp, probably crank shaft hp. Though, I've never read from where the pull is taken from. |
