auto-choke / idle problem?

Hi folks,

Long time lurker, first time poster looking for some advice if possible!

Similar to this post: I'm having problems except mine seem a little more severe.

I've owned an 2004 FZ6 for 6 months but recently as the warm weather has come in a problem keeps reoccurring. The bike was idling at 1500rpm from cold normally, but once the digital thermo gets to around 3 bars the idle revs drop to around 500rpm and the engine will ofc cut out consistantly whilst I am in my element (I commute 40 miles a day so this temp is regularly reached).

So I bumped up the idle to 1300 once its at 2 bars (which makes the bike sound a lot nicer) and i thought i'd fixed the problem but today, sunny, hot, 45 mins into my ride and clunk, revs are dropping to 500ish and stalling. I took it home and parked it, got under the tank and ready to try and change the idle and it stalls. I switch the ignition off then back on.. oh.. suddenly its idling at 1200 again and fine.

Has anyone else experienced this or have any idea whats going on? Is it possible to adjust the choke intensity at higher temperatures?

Its nice to know that turning the engine off for 30 seconds and back on might temporarily fix it but i'm worried i'm gonna stall it coming off the motorway and get splatted!

Thanks in advance for any help folks

Set the idle speed between 1250-1350 "after" the bike had reached the normal operating temperature. I'd wait until the radiator fan had cycled twice to make sure before touching the idle screw.

If sure that the idle speed is set correctly and the problem is not fixed, my guess is a faulty TPS.

To check the TPS, enter the diagnostic mode on the display and check that the throttle value on #1 is between 16-100 and the numbers don't jump erratically as you twist the throttle.

Good luck with your '04. I still have mine and still enjoying it.

segue00 said:

If sure that the idle speed is set correctly and the problem is not fixed, my guess is a faulty TPS.

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+1

If you call a yamaha dealership they should be able to tell you if the stock TPS was replaced already. If it was not, you can still get it done for free. They should have also marked the tag on your bike as laid out in the recall notice.

cheers guys i'm gonna warm it up, set the idle to 1350 and do the diagnostic stuff.

would the TPS problem reflect why the problems only occur at certain temperatures though or turning off the ignition for a few seconds resolving the problem? I'll let you know the findings in an hour or so

alsie said:

would the TPS problem reflect why the problems only occur at certain temperatures though or turning off the ignition for a few seconds resolving the problem?

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Absolutely :thumbup:

just ran the bike up to 4 blocks on the digital thermo then knocked the idle up to 1350rpm. the TPS readings are fine, 16 at closed and 100 open with steady increase between that. problem only seems to occur after 45+ mins of riding, so i'll find out if its sorted tomorrow

cheers for the advice, stay safe

so I rode to work today, came off the motorway and whump, the idle starts screwing up again. Dropped down to 800rpm, which makes sense given that I increased the idlespeed yesterday by about 300rpm (originally the problem was it dropping to 500ish when this weirdness occurs). pulled over, ignition off for 20 seconds, back on and the problem fixed --- til next time.

The engine was still nice and coolish so I don't think the auto choke is related to this problem. is my fuel injection screwing up? i'm loathe to go to the garage just yet without any indication of whats causing it - since its such an intermittant problem it could be the whole fix, pay - problem still there cycle

- in the meantime, is it worth popping the idle up again to keep the idle above 1k when this problem occurs? that would mean the bike idling normally at around 1600k or is that bad news.

thanks in advance.

alsie, seriously, it's your TPS (er code or not). I've read 20+ threads just like this one and I had the exact same problem as well...

You need to confirm that your original TPS is still in place (pick up the phone)

You need to confirm that your original axle nut lock washer is still in place (pick up the phone)

You need to make an appointment to get both changed out for FREE. And if I were you, I wouldn't mention the symptoms...I'd just tell them to change it without touching anything else.

LINKS to both official Yamaha "service bullitens" can be found here:

Awesome Tps News- Service Bulletin/Recall!!! - Sportbikes.net

alsie said:

the TPS readings are fine, 16 at closed and 100 open with steady increase between that.

Click to expand...

One word: intermitent

In affected motorcycles, an improperly designed Throttle Position Sensor (TPS) could cause an intermittently unstable idle when the engine is at idling speed when the motorcycle is stopped or during lowspeed operation. The engine could stall as a result. If the engine stalls after the operator disengages the clutch in a low gear while riding, the rear tire might slip momentarily if the operator abruptly re-engages the clutch. This could result in a vehicle crash with injury or death.

Click to expand...

DefyInertia said:

alsie, seriously, it's your TPS (er code or not). I've read 20+ threads just like this one and I had the exact same problem as well...

Click to expand...

this morning I called up the yamaha dealer i bought it off, they said its still under their used sales warranty. gonna print off the TPS recall stuff to make sure they replace it as standard and gonna call Yama tomorrow.

thanks for the advice!