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Discussion Starter #1
A few of us on here have experienced problems concerning a lag when you take off from a dead stop and then an immediate acceleration. It throws you off balance and is very alarming. Some of us have experienced fuel light problems. I had both.
The problem? The fuel pump.

After having my fuel pump replaced last week and riding it until one or both of these problems reoccurred, I am happy to say it is fixed.

I rode my 750 until something happened and I am pleased to say the fuel light came on at precisely the correct time. I fueled up with 2.8 gallons which means that there was approximately .7 gallons in the tank,....perfect !
No lag and leap problem was encountered.
I am now a happy camper,..er, rider. :)
 

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Awesome!!!! I have not had any issues since my last fix. But im going to run it down to the light and see if i have any of these issues.
Thanks for the info
 

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A few of us on here have experienced problems concerning a lag when you take off from a dead stop and then an immediate acceleration. It throws you off balance and is very alarming. Some of us have experienced fuel light problems. I had both.
The problem? The fuel pump.

After having my fuel pump replaced last week and riding it until one or both of these problems reoccurred, I am happy to say it is fixed.

I rode my 750 until something happened and I am pleased to say the fuel light came on at precisely the correct time. I fueled up with 2.8 gallons which means that there was approximately .7 gallons in the tank,....perfect !
No lag and leap problem was encountered.
I am now a happy camper,..er, rider. :)

About how many miles did you go before your light came on? I am trying to gage. My light came on when I had 40 miles on my odometer and I thought I was having issues, because I was told that they delivered my bike with a full tank, it was only when I ran out of gas on my second ride that I knew it was not a mechanical issue but a lying tongue issue.
 

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Anyone know what the mileage range might be? I know with idling, sitting in traffic and all it will make it vary a bit.
 

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I really wonder how it could be the fuel pump that is the problem... For it to only happen under certain conditions, I just don't see the logic.

Don't get me wrong, I'm ecstatic that the fix worked, I'm just gonna remain a little skeptical for now I s'pose.
 

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Discussion Starter #7 (Edited)
I really wonder how it could be the fuel pump that is the problem... For it to only happen under certain conditions, I just don't see the logic.
Makes perfect sense to me. That Lag-and-Leap thing we were experiencing was only happening when I was low on fuel,...of course I didn't know I was low on fuel because my light never came on.
The light sensor (fuel sensor) is in the fuel pump and when the fuel level gets low enough the pump can't pick up enough gas to supply the engine. Starting from a dead stop sends all the fuel towards the back of the tank and since the pick-up is towards the front of the tank it is momentarily starved of gas. (hence the lag). When the fuel is pushed back towards the front of the tank due to that lag crap, it leaps out from under you once the pick-up has a supply again.
It scared me to death a couple times when it did that and it is dangerous because when it lags like it did you have a tendency to give it more throttle and then when the gas is sloshed back up to the pick-up,....VRROOOOMM !
A novice rider would have been in trouble with a problem like that, and if I hadn't had a firm grip on the handlebars that 750 would have slung me off the bike.

Anyway,....there ya go. Problem solved.
 

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I really wonder how it could be the fuel pump that is the problem... For it to only happen under certain conditions, I just don't see the logic.

Don't get me wrong, I'm ecstatic that the fix worked, I'm just gonna remain a little skeptical for now I s'pose.
What is the problem with the fuel pump? Is it defective? Will there be a recall?

Makes me nervous to put down an order.
 

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Discussion Starter #9
What is the problem with the fuel pump?
Obviously there are some bad fuel pumps being installed at the plant. As far as any recalls? I have no idea, but I will bet you that Harley will ship a new fuel pump at Light Speed when requested.
 

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My fuel light came on @94.7 miles according to my trip meter.

Thanks for the information, that give me something to go by, I reset the trip meter when it was filled up last time, so I will more likely never let it get beyound the 90 miles point and considering I have not done a long ride, I will try to remember to hit the station before a ride if I have 40 to 50 miles on the trip meter. Running out of gas was the scariest feeling that I have eperience so far.
 

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Makes perfect sense to me. That Lag-and-Leap thing we were experiencing was only happening when I was low on fuel,...of course I didn't know I was low on fuel because my light never came on.
The light sensor (fuel sensor) is in the fuel pump and when the fuel level gets low enough the pump can't pick up enough gas to supply the engine. Starting from a dead stop sends all the fuel towards the back of the tank and since the pick-up is towards the front of the tank it is momentarily starved of gas. (hence the lag). When the fuel is pushed back towards the front of the tank due to that lag crap, it leaps out from under you once the pick-up has a supply again.
It scared me to death a couple times when it did that and it is dangerous because when it lags like it did you have a tendency to give it more throttle and then when the gas is sloshed back up to the pick-up,....VRROOOOMM !
A novice rider would have been in trouble with a problem like that, and if I hadn't had a firm grip on the handlebars that 750 would have slung me off the bike.

Anyway,....there ya go. Problem solved.
That's exactly what I mean though, the pump isn't the cause, its just reacting to not having any fuel to push to the injectors.
 

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Discussion Starter #12
I have talked to the service manager at my Harley dealer and requested that he look at the fuel pump that he removed from my machine and see who the manufacturer is. I was told that there are NO identification markings on the pump, so who makes the pump? I have no idea.

However,......If you have a pump problem you can call Harleys' toll free number @ 1-800-664-7762 and give them your VIN and they will overnight a fuel pump (I assume to the dealerships service department).
Harley IS aware of this problem.
 

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Discussion Starter #13
its just reacting to not having any fuel to push to the injectors.
It's hard to push fuel to the injectors when you are low on fuel and the fuel level drops below the pick-up. Actually I think the problem is where the pump is placed in the tank. In my way of thinking it should be all the way at the back of the tank just to get you over that last hill on the way to the gas station.:)
 

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I wonder if this is something that HD is actively looking into for the next model year or the one following that.
 

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Discussion Starter #15
I wonder if this is something that HD is actively looking into for the next model year or the one following that.

This problem might very well be why there are NO Harleys presently being delivered to the dealerships. I'll bet you the whole tank and pump is being redesigned.
 

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This problem might very well be why there are NO Harleys presently being delivered to the dealerships. I'll bet you the whole tank and pump is being redesigned.
I hope so. My opinion as an engineer (and an all around great guy :) ) is that the cause is not the pump, it is the tank.

I didn't know that the fuel pump is an in-tank unit. I actually find it a little surprising because there isn't clamp on the fuel hose leading out of the forewardmost part of the tank. Thats a whole seperate issue though.

When I get the bike back, I'm going to drop an inspection camera in and see exactly whats going on in there.
 

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Discussion Starter #17
My opinion as an engineer (and an all around great guy :) ) is that the cause is not the pump, it is the tank.
You might very well be correct, however since my low fuel indicator was not coming on, THAT problem was the pump. The rest is obviously the pump being starved of fuel.
Since my low fuel light now comes on and I keep sufficient fuel in it , I have encountered NO problems.
 

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This scares me

Makes perfect sense to me. That Lag-and-Leap thing we were experiencing was only happening when I was low on fuel,...of course I didn't know I was low on fuel because my light never came on.
The light sensor (fuel sensor) is in the fuel pump and when the fuel level gets low enough the pump can't pick up enough gas to supply the engine. Starting from a dead stop sends all the fuel towards the back of the tank and since the pick-up is towards the front of the tank it is momentarily starved of gas. (hence the lag). When the fuel is pushed back towards the front of the tank due to that lag crap, it leaps out from under you once the pick-up has a supply again.
It scared me to death a couple times when it did that and it is dangerous because when it lags like it did you have a tendency to give it more throttle and then when the gas is sloshed back up to the pick-up,....VRROOOOMM !
A novice rider would have been in trouble with a problem like that, and if I hadn't had a firm grip on the handlebars that 750 would have slung me off the bike.

Anyway,....there ya go. Problem solved.
I am a new rider and the thought of my bike doing this is not resting well with me....I wonder if I should mention this to my dealership to see if they heard anything. I had a deposit on my bike for over 2 months and last I heard, I am the only one sold so far, when mine came in, it was the only one that came in.
 

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It isn't the end of the world... and if the bike isn't pushed to its current limits, either performance, or fuel level wise - you'll probably be fine, and probably wont ever experience it.

My issue is that when I pay 8+ grand - its going to work as it should. I dont care what costs they incur in fixing the problem. They've made enough profit from me already - time for them to hold up their end of the deal.
 

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Discussion Starter #20
My issue is that when I pay 8+ grand - its going to work as it should. I dont care what costs they incur in fixing the problem. They've made enough profit from me already - time for them to hold up their end of the deal.
I totally agree.
 
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