Hesitant start-up

[Plymothian]

Hi all,

2004 FZ6 has been going great, but the last couple of months it's not been starting as well as it used to. It cranks over fine, and it does always fire up first time, but as soon as it fires up it only just gets going, and it takes a second before it's up to high idle. Previously it cranked over and then shot up to fast idle before my finger was even off the starter button.

The battery is only 4 weeks old, once started it idles fine, and it rides fine, no warning lights or error messages.

Any ideas what this could be? I'm not that worried, just confused as it never used to do this (even with an older battery). My guess was perhaps exhaust valve clearances have tightened? but not sure if this would affect only the hesitant start up.

p.s. it was serviced 6 months ago and has only done about 2000 miles since.

 

[FinalImpact]

Carefully lift the tank, prop it up and remove the air box lid. Towards the rear are 3 hoses. Two feed air to the idle circuit. If those two exhibit signs of debris building up that may be a tell tale sign its time to do some cleaning of thr idle air control valve.

Next is the coolant level and condition. If low on collant it may not actuate the high idle. Check those items and report back. Hint it uses heat into the IACV to change idle speed. If thats not working properly or someone messed with it, it may be part of the issue.

 

[Plymothian]

thanks, will check that at the weekend and report back.

 

[Plymothian]

well everything checks out, the coolant is a little low but still 3/4 between the low and full lines. Funnily enough it hasn't been doing it lately. I might have to give it a coolant flush in the winter anyway so perhaps that might sort it.

thanks,

 

[TownsendsFJR1300]

Here is the internal pic of the coolant IACV referred to in post #2;



Coolant flows thru those two hose nipples off to the right side

 

[FinalImpact]

well everything checks out, the coolant is a little low but still 3/4 between the low and full lines. Funnily enough it hasn't been doing it lately. I might have to give it a coolant flush in the winter anyway so perhaps that might sort it.

thanks,

When the engine is COLD, be sure to check the actual level at the Radiator cap. If the system has any kind of air leak, the reservoir level may not change. The coolant system relies on being able to HOLD PRESSURE up to ~ 16 lbs AND hold and retain a VACUUM. Its the vacuum that pulls coolant from the reservoir.

In short any debris in caught in the Radiator Caps inner most seal can defeat both of these functions but it won't leak to the outside world.

Did you remove the air filter lid and inspect the IACV air inlets? Basically looking into the two hoses, if dirty - that could lead to that Air Metering Valve sticking and not allowing change with engine temperature.

Source of pic: Bike P o r n http://www.600riders.com/forum/album.php?albumid=1339

:rockon::rockon: