So my bike wasn't runing very good lately and I had lost my reserve functionality out of my original petcock so I figured it was time to replace a few parts. I ordered the Pingel 1311 valve and the CVP tuner's kit and rebuild kit.

Well after an initial shake-down run, the bike is running like a champ, better than I ever remeber it. I do have a few issues though - I guess running it hard like I did accelerated a few oil leaks that were brewing, I guess the extra oil pressure pushed some out since I never really got above 3k in the past year or so and I was pushing it up around 5k today.

The other problem is it is pinging pretty bad now when I am in a high gear at low rpm and crank the throttle open 1/2 or greater. Does pinging usually result from bad carb tune (I may still need to dial it in) or too low of octane gas? I put 87 in it before making this run, I usually run 89 or greater, but it has stock pistons and rings so it should do fine on 87.

I also noticed what looked like water on the front of the carb after this run around the throttle cable linkages and above the accelerator pump. I didn't hit any puddles or any other water on this run so does anyone know if that could be a symptom of the pinging I heard some how?

Anyway, here is the screen from the old petcock. Probably the reason I didn't have reserve anymore...

 

It almost sounds like your accelerator pump is leaking and causing a low speed lean condition.I would take a flash light and while turning the throttle with the engine off look at the accelerator pump boot and see if gas is coming out of it and also look at the spray nozzle to see if your getting a good stream of gas coming out.

 

When you changed the fuel valve what did you do with the vacuum line. If it was not plugged the VOES would not work as it in series with the fuel valve. If the VOES is not working it will ping under load because it is not retarding the timing.

Oops! I was thinking wrong again. if the VOES is not working from no vacuum the timing would be retarded all the time. Sorry. Sometimes my fingers type faster than my brain works.

 

Judging from the amount of rust on the screen, I would believe that there may be a little water in your fuel. Perhaps trying another gas station. If you can find one that has three hoses at each pump, that's where you should go. If you only have one hose then when you get fuel you are getting up to a gallon of what ever was pumped last. So if you put three gallons in one third is a lower octane than what you paid for and this also lowers the octane.
John

 

Hey John, I never thought of that. I run 87 in the winter and 89 in the summer as the summer heat can require the extra octane to make sure it does not ping. So maybe I get some 89 in the winter and some 87 in the summer as the station where I get gas only has one hose for all three grades. At least it is gasoline with no alcohol. I guess what I should do is wait until someone comes in and fills up with 91, and then fill my tank. LOL

 

Here's a good article regarding detonation and pre-ignition: http://www.americanrider.com/output.cfm?id=1021915 According to this, the most common cause of what you are describing is jetting or changing the needle to the old Sportster needle.

Regarding all the rust from your tank, alcohol in the gas can be a good thing or bad depending. Alcohol will attract moisture and also is a cause of gas breaking down when sitting for long times. But if you're using pure gas (no alcohol) and there is water in it, adding a little alcohol (dry gas) will cause the water to be surrounded by the alcohol molecules and thereby pass through the system.

 

Accelerator pump diaghram was changed out when I rebuilt the carb, and I checked and it has a fine stream. The pinging is steady with the throttle. i.e., once I go 1/2 or more open in 4th or 5th at 1.5k to 2k it will ping steadily, not just when rolling on the throttle. Once I get above 2.5k, it seems to go away.

 

A stock evo should run fine on 87 though, right? Only mod to this bike is the EV-27 cam, and carb jets to go along with it. (46 & 185)

 

After reading that article, example #2 is more like what I have. The funny thing is, I had really no pinging before, and now I do even though I went from a 42 jet to a 46. The mixture/timing aspect is probably more my main issues. My vacuum is hooked up to the voes, but I have no idea if that is operating properly or not.

IIRC, a retarded ignition should ping less, right?

Anyway, I was messing with the mixture screw today after washing the bike and per the included intructions, I was supposed to 'tighten' the screw until the engine started to stumble and then back out 1/4 of a turn. Well, I was able to tighten that screw all the way until it stopped and my engine never stopped or stumbled. I'm a little confused/concerned about that. Perhaps my o-rings have disintegrated? However, wouldn't this cause the mixture to be rich and therefore reduce the odds of the engine pinging?

 

Was the engine up to operating temp.? And warm idle? Tighten adjuster until it stumbles, then loosen until it stumbles. The settings 1/2 way in between.