Bike running hot, difficult to start when warm
Bike running hot, difficult to start when warm
Hi Guys,
I've had this issue for a while, well ever since I bought the bike. The bike is a 2010 FXDF Fatbob. Previous owner took baffles out of stock pipes and probably didn't re program settings (I think).
The bike starts easily, really well when cold. It runs perfectly, but it appears to be running quite hot. When the bike is warm, it is sometimes or usually difficult to start. I suspect that it is too lean, but I did not get it checked yet.
Is there something I can do to richen it or improve this ?
Thanks
I've had this issue for a while, well ever since I bought the bike. The bike is a 2010 FXDF Fatbob. Previous owner took baffles out of stock pipes and probably didn't re program settings (I think).
The bike starts easily, really well when cold. It runs perfectly, but it appears to be running quite hot. When the bike is warm, it is sometimes or usually difficult to start. I suspect that it is too lean, but I did not get it checked yet.
Is there something I can do to richen it or improve this ?
Thanks
Extreme HDF Member
Joined: Sep 2006
Posts: 10,114
Likes: 29
From: Vancouver B.C. Canada
103?
Well, Piston rings expand when they get hot, even my SB 96 was hard to start when it got hot. Since I installed compression release, no more problem. I see you location in China, it could get really hot and humid I believe. Do you have a oil temp gauge? How hot do you know? It's hard to judge what it is.
Well, Piston rings expand when they get hot, even my SB 96 was hard to start when it got hot. Since I installed compression release, no more problem. I see you location in China, it could get really hot and humid I believe. Do you have a oil temp gauge? How hot do you know? It's hard to judge what it is.
96 ci. No I don't have the oil gauge but was meaning to get one, so it's only by "gut/feel" that I say its running hot.
That said, was also knowing that they come lean from the factory for emissions purpose and the previous owner pulled out the baffles i'm sure without re-setting the mixture.
That said, was also knowing that they come lean from the factory for emissions purpose and the previous owner pulled out the baffles i'm sure without re-setting the mixture.
It's not like it turn and turn and finally starts. On numerous occasions it kills the battery and I need to put the jumper cables on it. When cold, I just have to stare at the start button and it starts (ok little exaggeration there).
Was not terribly hot, so I was thinking it didn't really have to do with outside temp. But ya never know.
Was not terribly hot, so I was thinking it didn't really have to do with outside temp. But ya never know.
It does sound like it's running lean. A couple of questions.
Is the AC stock or aftermarket?
You mentioned the baffles. Is there a cat converter in the collector pipe? I don't remember what year-models came without cats.
If you still have a cat, the lack of baffles shouldn't make much difference in air/fuel. A little difference, but shouldn't be enough, by itself, to cause the problem.
If you have an aftermarket AC, no cat and no baffles, it is definitely lean without proper tuning.
Before you do anything else though, check your battery connections and the ground connection at the other end if the ground cable. A lightly loose or corroded connection can cause this.
If everything is connected properly, add some Xied resistors to the sensors. These will Richey the mix. They aren't a proper tune, but they work. Alternatively ($$$) buy a tuner and have it adjusted properly.
Is the AC stock or aftermarket?
You mentioned the baffles. Is there a cat converter in the collector pipe? I don't remember what year-models came without cats.
If you still have a cat, the lack of baffles shouldn't make much difference in air/fuel. A little difference, but shouldn't be enough, by itself, to cause the problem.
If you have an aftermarket AC, no cat and no baffles, it is definitely lean without proper tuning.
Before you do anything else though, check your battery connections and the ground connection at the other end if the ground cable. A lightly loose or corroded connection can cause this.
If everything is connected properly, add some Xied resistors to the sensors. These will Richey the mix. They aren't a proper tune, but they work. Alternatively ($$$) buy a tuner and have it adjusted properly.
Ultimate HDF Member
Joined: Jul 2011
Posts: 5,477
Likes: 5
From: New Braunfels, Texas
Doing a proper stage one will cool it down a bit but it's probably time for a new batterty. I've already replaced mine on my 2011 and if it's a really hot day the starter may go a tad slower but it starts instantly.
Heat kills a battery in a few years.
Heat kills a battery in a few years.
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In reference to my previous post. The battery connections shouldn't cause it to run hot, just the hot starting issues. More than likely, it's air/fuel. Your battery does sound well used though based on the need to charge it and the full drain issues.
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Tourer
Joined: Oct 2012
Posts: 394
Likes: 2
From: Summerville, SC
I had this problem on mine as well, but it never ran my battery down...just had to crank it for a while. I found that if I hit the start button without waiting for the check engine light to go out, it starts right up every time.
Road Captain
Joined: Sep 2013
Posts: 536
Likes: 7
From: California
Pull The Spark Plugs............
Hi Guys,
I've had this issue for a while, well ever since I bought the bike. The bike is a 2010 FXDF Fatbob. Previous owner took baffles out of stock pipes and probably didn't re program settings (I think).
The bike starts easily, really well when cold. It runs perfectly, but it appears to be running quite hot. When the bike is warm, it is sometimes or usually difficult to start. I suspect that it is too lean, but I did not get it checked yet.
Is there something I can do to richen it or improve this ?
Thanks
I've had this issue for a while, well ever since I bought the bike. The bike is a 2010 FXDF Fatbob. Previous owner took baffles out of stock pipes and probably didn't re program settings (I think).
The bike starts easily, really well when cold. It runs perfectly, but it appears to be running quite hot. When the bike is warm, it is sometimes or usually difficult to start. I suspect that it is too lean, but I did not get it checked yet.
Is there something I can do to richen it or improve this ?
Thanks
As stated in prior post's........
Cat converter should still be intact in the collector on the header, so pulling baffles should not change the fuel mixture...........
Could be a weak battery...........or lose connection's..............
You really need to know how hot she is running, that could tell you a lot right there....
Starter may be going out as well, when she is hot, she may not be turning quite as hard, as when cold...............
Start with the obvious, and eliminate each as you go............
Good luck.............let us know what you find..................