High revs after re-fueling.

[Tezza_imp]

I've noticed after I fill the tank that the engine revs high when I first start the engine. My bike has always done this and it has never been a problem and it only lasts for a couple of seconds. Has anyone had a similar problem.

 

[Pterodactyl_imp]

Maybe not a problem. When the engine is cold the ECU schedules a higher idle RPM, amongst other things. Up around the 1600RPM mark. Maybe, in colder weather, when you refuel, the engine, or at least the point of temperature input, cools enough for this to take effect for a short period. After starting the residual heat plus the engine returning to normal operating temperature soon brings the idle speed to normal. That's my guess anyway.

Cheers

 

[Tezza_imp]

Sorry, should have been more specific. It only happens when I pull into a servo and fill up. Engine is hot. Sometimes revs up to around 3000 rpm for a second or so.

 

[Pterodactyl_imp]

Check throttle for sticking? After that I'm done.

 

[flynrider]

Sorry, should have been more specific. It only happens when I pull into a servo and fill up. Engine is hot. Sometimes revs up to around 3000 rpm for a second or so.

Are you sure you waited until the computer boot was finished before hitting the starter? On my bike, if I hit the starter before the gauges have completed their startup sequence, the bike will rev up exactly as you describe.

 

[Pterodactyl_imp]

Sorry, should have been more specific. It only happens when I pull into a servo and fill up. Engine is hot. Sometimes revs up to around 3000 rpm for a second or so.

Are you sure you waited until the computer boot was finished before hitting the starter? On my bike, if I hit the starter before the gauges have completed their startup sequence, the bike will rev up exactly as you describe.

Hey, good thinking. I always allow mine to cycle through prior to thumbing it.

Cheers

 

[Cormanus]

I've been know to forget to allow the computer to cycle completely before starting and don't recall it revving like that. Might have to go out and try it.

 

[Cormanus]

Tried a couple of times when I was out today and noticed two things: the first was a momentary roughness the first time; the second was a slight momentary increase in revs, but not up to 3000 rpm.

 

[Pterodactyl_imp]

Mmmmmm. Hey Tez, what kind of oil are you using?

Cheers

 

[Cormanus]

Dr Dactyl's HUBRIS Omnigrade Motorcycle Oil, I believe. He's about 2,451 kms left before the bike carks it.

 

[xNE0x_imp]

Make sure you don't touch your throttle before starting. Start bike. Should idle fast for a few seconds, then come down as it warms up. If the idle stays high, check your throttle cables for out of adjustment and adjust per spec.

 

[flynrider]

Tried a couple of times when I was out today and noticed two things: the first was a momentary roughness the first time; the second was a slight momentary increase in revs, but not up to 3000 rpm.

Interesting. I've only done it a few times (by accident). Some days I forget which bike I'm riding. Occasionally, I turn the key on the CB750 and find myself waiting for the fuel pump sound and gauge cycle.

Both times I did it I got a high rev. I wonder if results vary depending on what point in the boot process you hit the starter?

 

[Cormanus]

Oh, deary me, I can see hours of fun with a stop watch ahead of me. Not.