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Discussion Starter #1
As of April 20th, the NHTSA looks to have opened an investigation into the "Lag and Leap" issue so many of us have been dealing with.

Details here! (You'll need to click on the "Investigations" tab)

Hope this leads to something positive for us owners.
 

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As of April 20th, the NHTSA looks to have opened an investigation into the "Lag and Leap" issue so many of us have been dealing with.

Details here! (You'll need to click on the "Investigations" tab)

Hope this leads to something positive for us owners.
I would also advise any US owners that have experienced the lag and leap problem to report it to the NHTSA. They only have a very limited number of reported cases and they depend upon input from the public in determining the extent of the problem.
 
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I know I saw two reports that resulted in a crash when looking at their reports. They both might have been for the XG500 (one was mine). Good to see they are looking in to it.
 

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if your'e bike lags or stalls, check to see if ur tank is venting.

there is a little rubber plug just under the gas cap. if the hole in the plug is closed, the tank won't vent, allowing pressure to build up staving the pump of gas.
 

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if your'e bike lags or stalls, check to see if ur tank is venting.

there is a little rubber plug just under the gas cap. if the hole in the plug is closed, the tank won't vent, allowing pressure to build up staving the pump of gas.
I dont understand the logic behind this.
 

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I dont understand the logic behind this.


Fuel Tank Venting
Your tank has to breathe. In order to breathe, your tank must have a vent somewhere that will relieve both vacuum and pressure. Gasoline expands in volume as it warms up and shrinks in volume as it cools down. The fuel level of your tank changes throughout the day, even if you are not driving it.

You cannot put fuel into your tank, unless you can get the air out...and you cannot withdraw fuel from your tank unless you can let air in.

Up through the 1960's, most vehicles used vented gas caps. This is simply a gas cap with a hole in it. Unfortunately, this hole would allow the fuel to splash out when accelerating or turning a corner.

If you are running a vent line it is important that the line is ran higher than the highest point on the tank including the fuel filler neck. Also, the vent line cannot have a dip in it where fuel or condensation can get trapped in the line. If fuel becomes trapped in the line your tank will then build pressure or vacuum until there is enough pressure to purge the vent which will cause gas and/or odor to come from the vent line. If enough pressure builds up damage could be caused to your tank.
 

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Fuel injected vehicles require a vented system.either through the gas cap or tank. Otherwise they pull a vacuum on the system and starve the injectors.
 

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Discussion Starter #15
Harley dealer just informed me this recall was non-existent and that it is for a rear reflector on the bike. They also made it sound like at the end of the day they don't really care.
If you're referring to a recall about the lag and leap, it's because there is no recall yet. Click the link in the original post, the NHTSA has opened an investigation. This, in turn, could potentially lead to a recall in the future. It depends on their findings.

There is a current recall on bikes that might be missing reflectors. Upon inspection, my bike would be part of that recall, but since I'm going to just eliminate that whole fender, I'm not going to bother.
 

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if your'e bike lags or stalls, check to see if ur tank is venting.

there is a little rubber plug just under the gas cap. if the hole in the plug is closed, the tank won't vent, allowing pressure to build up staving the pump of gas.
Our tank vent was installed backwards, causing vapor lock in the tank and unpredictable power surges.
 

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if your'e bike lags or stalls, check to see if ur tank is venting.

there is a little rubber plug just under the gas cap. if the hole in the plug is closed, the tank won't vent, allowing pressure to build up staving the pump of gas.
I'm going to take a look at mine on my lunch break in a couple hours! I've gone through one tank of gas so far. The low fuel light came on with about 90 miles on the odometer. I figured I should have gotten WAY farther but maybe the dealer didn't fill it all the way. It was lurching when I drove into the station and when I took the cap off, there clearly was pressure and I heard the air rushing out.
 

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I had the lag and leap issue early on, and was one of the first to file a claim, as well as constantly nag both HD corp, and my local dealer. The issue was the fuel pickup sock inside the tank. It had partially separated from the fuel pump, allowing air to be sucked into the pump. Since mine was repaired, I have had no further issues. For more info, search my username, or the threads here on this site.
 

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Happened to me after 2000 miles on the bike

This afternoon I was glad to have read so much about this issue, so when my bike stalled and surged (stumbled?),I was able to go through it without panic. Not panicking seems to have been helpful in dealing with it. I just held the throttle steady and the stalls and surges diminished within seconds. I don't think I have the reflexes to have done anything different to manage it. Although, I think I probably decreased the throttle a little. I certainly did not come all the way off of the throttle when it happened. Was happy this happened on very empty streets on Sunday afternoon and not in traffic, which some of you have described. Below is the complaint I just filed.
This is the same issue as found in investigation PE15015. This is the first time I have experienced engine stumble (stall), commonly referred to as Lag and Leap. This occurred when I had a low fuel level in my tank, (tank was filled 10 miles later with 3.1 gallons into a 3.5 gallon tank). When accelerating from a stop into a right hand turn I experienced a near-stalling of my engine. I did not adjust throttle and very quickly after that stall a surge in engine rpm occurred with brisk acceleration, followed by another near-stalling and another surge. A third less noticeable episode occurred after that. I did not adjust throttle position throughout the episode. The timespan over which this took place was probably 2-3 seconds. I am familiar with the complaints which have been around this issue and so was confident that i would be able to get through the episode without losing control of the bike. Several minutes later and after another stop with very slow acceleration from it, during which the stall and surge did not occur, I decided to test whether it would happen in 2nd gear on a straight trajectory. At about 20 mph I accelerated in 2nd gear and again 3 cycles of stall and surge or Lag-and-Leap did occur, with the 2nd one being most noticeable and the third being very minimal. I was happy I was able to make a left turn across two lanes of road to get into the gas station, without it occurring again. I drove another 40 miles after filling my gas tank without it happening again. I had previously filled my tank with 3.4 gallons during a ride when my motorcycle had 1000 miles on it, without this phenomenon occurring.
 
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