A week ago I took my 2007 FXDC to Harley-Davidson of Long Branch, NJ for the 10,000 mile service. I rode my bike 30 miles at all speeds, from 30mph up to 80mph on the way there - and the bike ran fine. I had a full tank of 93 octane Sunoco when I took the bike in.

Whe I picked the bike up and rode it home, the engine was pinging like crazy (pre-ignition) upon acceleration in 1st, 2nd and 3rd gears. My bike has a V&H FuelPak, SE Stage 1 air cleaner, and V&H Straigtshots slipons.

I rode the bike about 100 miles yesterday and the bike was pinging only upon hard acceleration in 4th and 5th gears.

Today (Oct. 12), I rode 150 miles and the pinging was noticeable under hard acceleration in 3rd, 4th and 5th gears. However, what was new, was when I was riding home on Route 287, at a steady 70mph-80mph in sixth gear, the engine was pinging like crazy - steady pinging as long as I held the throttle open.

The bike runs fine - meaning the powerband is what is has been since I did the Stage 1 upgrades last June. It's just the pinging cannot be good for the engine.

Could the dealer have done something to my bike to cause this? It NEVER pinged at steady speed in the 60-80mph range before. Or, am I just the victim of bad gas? I refilled about 1/2 tank this morning again with Sunoco 93 octane. I have also re-checked my FuelPak settings and they are correct for my bike and exhaust system.

I went out and pulled the plugs. They are the correct plugs (HD 6R12). What I found was that the gap was too large on both plugs (was .045 and should be between .038 and .043) and that the rear plug was burning just fine, but that the front plug was burning hot (electrode was white on top). I regapped the plugs to .040. Anyone have any suggestions why the rear cylinder is running okay and the front one is running hot? (the front one is probably doing the pinging). Usually it's the rear cylinder that runs hot as it is not directly in the air flow.

Anybody have any ideas? As far as I know, the only ignition related component that was changed were the two spark plugs.

Thanks,
Richard...

 

I would check the fuel pak connections and quite possibly the the program on the fuel pak got changed.

 

What does pinging sound like ? I have V/H SS short shots on my fat bob with a pc111. The bike runs excellent but all this pinging talk has me wondering. Will I be able to hear the pinging with the loud pipes ? Just wondering.

 

Call the dealer and ask them what they did.

Pretty interesting it did not ping before they serviced it.

I would take it back in.

If no joy with the dealer, purge your gas and check the settings on your fuel pak. Maybe the fuel pak isn't working, shorted?

 

check the fuel-pack connections.and think about taking back to the dealeror it could be a injector clocked or going bad.

 

I will check the FuelPak's connections and settings this morning and then give it a test drive.

Richard

 

Well good news and bad news. The pinging (knocking) seems to have gone, but I don't exactly know why. What I did was as follows:

1. Re-gap spark plugs to .040 (dealer had apparently not gapped them during the 10,000 service and the gap was .045 (gap should be from .038 - .043)
2. I disconnected my Vance & Hines FuelPak from the electrical harness, reconnected it, and validated the FuelPak settings for my bike (2007 FXDC) and exhaust system (V&H Straightshot HS Slipons)
3. I had 2 gallons of gas left in the tank - so I put in 6 oz. of Techron fuel system cleaner then went to the Raceway gas station and put in 3 gallons of 93 octane (tank holds 5 gallons)
4. Went for a 30 mile ride. After warming up the bike for 5 miles, I accelerated in each gear very hard up to 60mph - no pinging. Then I cruised for 5 miles at 60mph in 5th gear - no pinging and power is what it should be. Then I cruised for 2 miles at 80mph in 6th gear - no pinging. The ambient temperature is 68 degrees Fahrenheit, low humidity. These are the same weather conditions I had yesterday when the bike was pinging like hell while accelerating and especially when cruising at 70mph or over. Of course yesterday it was pinging like hell at 70mph after 130 miles of riding. So I don't know if that made any difference.

The only slight pinging I could induce was when I intentionally lugged the engine in 5th gear.

Bike seems to run fine now. I ran it 30 miles and up to 80 mph, so it was definitely warmed up. I really wish I knew why it's not pinging now.

I am certainly not a pro mechanic, but I think that Sporty2003 is onto something being that it was only the front cylinder that was running hot. It doesn't take much to clog a fuel injector pintle. I am wondering if the Techron, which I have used for 20 years in direct port fuel injection cars, did anything?

Thanks for those who gave input.

Richard

 

mynzbtr1,

Pinging (detonation, also called knocking or pre-ignition) sounds like a very fast, high pitched, metallic rattle. When you hear it you'll know it. Regardless of the loudness of your exhaust system, you'll hear it.

Richard

 

I would think it is injector related as well... run a diagnostic and see what the bike is telling you... have you got and engine light?

 

No - no light.
Richard