When bike is cold it starts in 1 crank, when hot it takes about 7 cranks to start Why?
#1
When bike is cold it starts in 1 crank, when hot it takes about 7 cranks to start Why?
I have a 07 road king when my bike is cold it starts on the first crank. When it is hot it takes about 6 or 7 cranks to start. When I first notice starting hard it would take about 3 to 4 cranks it seams to me it is getting harder to start over time. Could it be the battery going bad the bike is almost 2 years old.
#2
RE: When bike is cold it starts in 1 crank, when hot it takes about 7 cranks to start Why?
There are several responses in related threads, but none seem to point toward a single cure...I'm not too familiar w/EFI for bikes, but the symptoms sound like vapor lock - heated fuel bascially boils in fuel lines, fuel pump doesn't like air and fuel doesn't flow into injectors efficiently until the line cools and boiling stops - usually 20-30 mins...This is very common on piston airplanes w/fuel injection (also air cooled) where everything is tightly packed into a small cowling...Take away the airflow and everything gets hot as hell...Fortunately, airplanes have electric fuel pumps you can use to purge the boiling fuel out...Not sure what to do w/a bike other than let it cool or crank it until the line clears. \\;
Two ways you might use to diagnose...
Get the bike hot by riding it...Don't let it just sit there...You need to get the normal airflow over the engine...Then shut it down and try to restart it IMMEDIATELY before the lines get hot...If it starts right away, vapor lock may be the issue...If not, you probably have another problem. \\;
If it's vapor lock, you may want to check to see what part of the line is getting too hot...Wrap 3 or 4 layers of foil around the line at a suspected hot spot...then get the engine hot and see if the restart problem is solved...If so, reroute that portion of the fuel line away from the heated area. \\;
Two ways you might use to diagnose...
Get the bike hot by riding it...Don't let it just sit there...You need to get the normal airflow over the engine...Then shut it down and try to restart it IMMEDIATELY before the lines get hot...If it starts right away, vapor lock may be the issue...If not, you probably have another problem. \\;
If it's vapor lock, you may want to check to see what part of the line is getting too hot...Wrap 3 or 4 layers of foil around the line at a suspected hot spot...then get the engine hot and see if the restart problem is solved...If so, reroute that portion of the fuel line away from the heated area. \\;
#3
RE: When bike is cold it starts in 1 crank, when hot it takes about 7 cranks to start Why?
happens to my 08 SB sometimes,, its almost like vapour lock of old,, but it always starts after a couple of cranks so i dont worry about it and its only started doing it since the stage 1 with a PCIII fitted so i figured that would be the issue..
#4
RE: When bike is cold it starts in 1 crank, when hot it takes about 7 cranks to start Why?
I had this problem on my 07 Bob after stage 1 upgrades. If you have a SERT you can adjust the cranking fuel table which is temp based. Once I tweaked the numbers a bit it start usually on the first or second crank. I'm not sure if the PCIII has that adjustment available.
#5
RE: When bike is cold it starts in 1 crank, when hot it takes about 7 cranks to start Why?
Do you keep a Smart Tender on your 2 year old battery? If not that maybe the culprit. It does take more amps to turn and start a hot engine. The way you desribe it first being 3-4 cranks and then now 7+ cranks it sounds like a degrading battery.
#6
RE: When bike is cold it starts in 1 crank, when hot it takes about 7 cranks to start Why?
The weird thing I call 4 Harley shops and each one told me a different thing one said the starter one said a problem with the fuel one said a battery. I will check the battery I do have a smart tender on my bike I put it on because one day my battery went dead on me. I like the idea of a vapor lock (tank’s bharvey60) come to think about it the hotter the air temperature gets the more crank’s it takes to starts the bike. I use to have a sert on my bike and I did play with the starting fuel but I took it off the bike and put the stock ECM back on.
#7
Join Date: Mar 2007
Location: Woodstock, Ont , Can
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RE: When bike is cold it starts in 1 crank, when hot it takes about 7 cranks to start Why?
For what it's worth my softail with stock ecm sometimes would not fire at all when hot unless I stopped and hit the starter button again. Then it fired right up. With tmax ecm it fires on first or second compression hot or cold. I believe it was somehow related to ignition not coming online when it should. Recycle the key and it would work also.
Ron
Ron
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#8
RE: When bike is cold it starts in 1 crank, when hot it takes about 7 cranks to start Why?
Good idea I did not think of the ignition coming on, It seem like it could anything, the only clue is it happens when the bike is hot. I heard some where that if something happens to the ECM it will reboot the stock map. I did have a stage 1 download in the ecm and when I was using a tmax (this great ecm easy to use and fun to play with) I remove the stock ecm and put it on the shelf for about 6 months when I put it back in the first time I started my bike it ran like doggie du then I turn it off real fast then started up again and it ran fine. I think I interrupt the boot processes and it went back to stock ECM map which means the bike real run lean (hotter) because of the stage one modifications. I know one thing my bike gets great mpgs 46 and I have nightrider’s O2 IED’s on. Please punch holes in my theory.
#9
RE: When bike is cold it starts in 1 crank, when hot it takes about 7 cranks to start Why?
ORIGINAL: ubreal
Good idea I did not think of the ignition coming on, It seem like it could anything, the only clue is it happens when the bike is hot. I heard some where that if something happens to the ECM it will reboot the stock map. I did have a stage 1 download in the ecm and when I was using a tmax (this great ecm easy to use and fun to play with) I remove the stock ecm and put it on the shelf for about 6 months when I put it back in the first time I started my bike it ran like doggie du then I turn it off real fast then started up again and it ran fine. I think I interrupt the boot processes and it went back to stock ECM map which means the bike real run lean (hotter) because of the stage one modifications. I know one thing my bike gets great mpgs 46 and I have nightrider’s O2 IED’s on. Please punch holes in my theory.
Good idea I did not think of the ignition coming on, It seem like it could anything, the only clue is it happens when the bike is hot. I heard some where that if something happens to the ECM it will reboot the stock map. I did have a stage 1 download in the ecm and when I was using a tmax (this great ecm easy to use and fun to play with) I remove the stock ecm and put it on the shelf for about 6 months when I put it back in the first time I started my bike it ran like doggie du then I turn it off real fast then started up again and it ran fine. I think I interrupt the boot processes and it went back to stock ECM map which means the bike real run lean (hotter) because of the stage one modifications. I know one thing my bike gets great mpgs 46 and I have nightrider’s O2 IED’s on. Please punch holes in my theory.
im not trying to rob thread... but... can you tell me why you removed tmax and put stock ecm back in bike?
 \\;
thanks
#10