GSX1400 Owners .org

Technically Speaking => General Technical discussion => Topic started by: neil on Monday, 04 September 2017, 08:53 AM

Title: PROBLEM STARTING WHEN HOT
Post by: neil on Monday, 04 September 2017, 08:53 AM
MY BIKE WILL START FIRST TIME EVERY TIME WHEN ITS COLD BUT WHEN I TAKE IT FOR A RUN WHEN I SWITCH IT OFF IT WILL NOT START, I HAVE TO WAIT 10-15 MINUTES THEN IT WILL START AS IF NOTHING IS WRONG, HAVE TRIED LOADS OF SOLUTIONS SO I THOUGHT BUT TO NO AVAIL. CAN ANYBODY GIVE ME A SOLUTION. CHEERS NEIL
Title: Re: PROBLEM STARTING WHEN HOT
Post by: KiwiCol on Monday, 04 September 2017, 10:28 AM
How long has it done this Neil? Just started recently? If so, had you been doing any 'maintainence' just prior to it starting?
Sounds like vapor lock to me, but that'd be odd.
Checked your tank breather is clear n not kinked? Try opening the filler cap n close again n see if it starts after that.
Title: Re: PROBLEM STARTING WHEN HOT
Post by: Rod G on Monday, 04 September 2017, 03:12 PM
I'm not familiar with fuel injectors, but this has rich mixture written all over it. Whatever tells the injectors for more fuel when cold, keeps up the message when hot, rather than leaning it out some.  Fix?  God only knows.   
Title: Re: PROBLEM STARTING WHEN HOT
Post by: KiwiCol on Monday, 04 September 2017, 03:24 PM
I think we need a bit more info from Neil to accurately point him in the right direction.  Like, how does it run when hot? bit smokey - black/grey? What's the exhaust pipe like? Sooty?  Does it pull all the way to redline nice & smooth?

Could be an out of adjustment TPS, which is usually easy enough to re-set.  Could be blocked air cleaner, but then it would be there all the time & not start in 15 min.   That's why I was thinking vapor lock or no breather to tank, in 15 min it'd equalise & go again.
Title: Re: PROBLEM STARTING WHEN HOT
Post by: lawrie on Monday, 04 September 2017, 05:24 PM
As you are having to wait 10-15 mins, it suggests it might be a 'temperature' thing, i.e. waiting to cool down??
There are several sensors dotted around the engine, oil pressure & temp, & air pressure & temp, its possible that the ecu is getting a false reading from the IATS  (Intake Air  Temp Sensor) in the airbox  & messing up the injection ( there is no choke ) .
Another thing to try, put your head down by the tank, & listen for the fuel-pump priming up the fuel pressure for a few seconds as you switch on, you MUST hear this or she won't start.
Have you tried the self-diagnostics to see if there's an error-code?
Title: Re: PROBLEM STARTING WHEN HOT
Post by: grog on Monday, 04 September 2017, 07:13 PM
Neil, more info needed. spins n no start? smoke, fuel smoke when it does? gauges sweeping? fuel pump working? or just nothing happens?
Title: Re: PROBLEM STARTING WHEN HOT
Post by: seth on Monday, 04 September 2017, 08:19 PM
as already said the more info you can give the better the reply on what to check.
:cheers:
Title: Re: PROBLEM STARTING WHEN HOT
Post by: Blubber on Monday, 04 September 2017, 08:42 PM
and Welcome to the forum Neil  :hat:
Title: Re: PROBLEM STARTING WHEN HOT
Post by: neil on Wednesday, 06 September 2017, 05:02 AM
sorry for late reply have been away, when the bike wont start it try,s to turn the engine but not enough power almost like the battery is flat, there,s no smoke when it starts cold and it runs and ticks over fine.
Title: Re: PROBLEM STARTING WHEN HOT
Post by: seth on Wednesday, 06 September 2017, 05:18 AM
check the frame earths  :cheers:
Title: Re: PROBLEM STARTING WHEN HOT
Post by: KiwiCol on Wednesday, 06 September 2017, 10:28 AM
Ok, well this is a different angle to my first thoughts.
Electrical by sound of it. I'd be doing a process of elimination of what it isn't.
Start with the battery, how old is it? What's it's resting voltage, start the bike, check the voltage whilst starting, check the charging at idle, check the charging at 2500. Go from there.
Title: Re: PROBLEM STARTING WHEN HOT
Post by: KiwiCol on Wednesday, 06 September 2017, 05:28 PM
It wouldn't be the first to have an old battery giving odd problems. The voltage can still be up to a good level (12.65v is a good condition battery, fully charged) but still not be able to supply the required load to start. This can occur when you have a cell that's gone or going dead. The charging system bangs 13.7 - 14.7 volts into it, 1 cell is on the way out & so the remaining cells get 'over charged' & can get up to 2.5 - 2.6v per cell, times that by 5, gives you 12.5 - 12.6 volts, but not enough amperage to start.

So, after all that, voltage isn't everything & just because you have 12.5 odd volts doesn't necessarily mean your battery is still good.

Check your battery voltage & charging voltage as above, then you'll know if the bike is actually charging correctly, if not, there's where to look first.  If your battery is old, like 5+ years (Yes I know some have had batterys much much longer, me inc) would probably pay to load test it to check it's condition. This is easy to do at home if you have a load tester, if not, your local sparky shop will have one for sure.

Will see were others start on the issue.
Title: Re: PROBLEM STARTING WHEN HOT
Post by: gsxmad on Thursday, 07 September 2017, 04:03 AM
Hi Neil had the very same problem with my 14.I took out the starter motor opened it up put new brushes in it. I also sanded the armature with 400 grit sand paper then cleaned out the grooves in the armature after sanding.The bike starts perfect ever since.Hopefully this might be of some help to you.Best of luck.
Title: Re: PROBLEM STARTING WHEN HOT
Post by: neil on Sunday, 15 October 2017, 08:35 AM
changed the starter motor and this solved the problem, thanks for all the advise.
Title: Re: PROBLEM STARTING WHEN HOT
Post by: Kiwifruit on Sunday, 15 October 2017, 06:13 PM
Welcome Neil. Dont be a sranger.
Pleased you solved your problem  :onya: