Could my TPS be rooted? Or am I just F*CKED in the head?

[Super T.I.B]

When I got to work this morning, idling my bike into its' cosy parking spot, the engine just started revving its tits off for no reason.

Went up to around 5k and no amount of blipping the throttle would bring it back.

Have noticed it once before, last week I think, when it revved up to around 3k. Later on in the day when I went to start it, everything seemed fine so I rode home without any probs.

Will keep an eye on it, has anyone else had this issue? Any words of wisdom that I can use?

For the uneducated: TPS = Throttle Position Sensor. 

[craigo]

There's a sensor on the throttle? I though it was a good ol' fashioned cable with spring return.. At least that what it looked like on my 620.

Could it be a sticky choke or throttle cable?

[tricolore]

In answer to your question, dunno. Was there slack in the throttle when it was revving? did it stop itself or did you shut it down? Did the revs rise gradually on their own or did it stay up after you twisted the throttle?
At the risk of catupaulting into traffic, should you be riding it?

[bigiain]

There's a sensor on the throttle? I though it was a good ol' fashioned cable with spring return.. At least that what it looked like on my 620.

Yeah, all the injected bikes have a sensor - it's one of the inputs to the ECU. I don't think it terribly likely to cause the symptoms described though - a dodgy sensor would change the amount of fuel the computer injects, but to bump the revs up requires air as well as fuel, and the tps would have to be _properly_ buggered to be holding the throttle butterflys open.

Could it be a sticky choke or throttle cable?

That's _much_ more likely in my experience. Adam, did this happen when the bars were turned all the way to one side (most likley the left)? That'd indicate a cable routing problem (which could be either the throttle or the fast idle cable - I know Melvin's bike has the fast idle routed in a way that bumps the idle up a few hundred rpm with the bars all the way to the left...)

big

[Super T.I.B]

That's _much_ more likely in my experience. Adam, did this happen when the bars were turned all the way to one side (most likley the left)? That'd indicate a cable routing problem (which could be either the throttle or the fast idle cable - I know Melvin's bike has the fast idle routed in a way that bumps the idle up a few hundred rpm with the bars all the way to the left...)

big

Yeah Big, I just checked it. Moving the bars to the left made the fast idle move. Which makes me think of the times it has happened, this afternoon when I was reversing out of a parking space, bars to the left, up go the revs. I wheeled it back into the space and stopped it. Restarted and reversed left, happened again. F*CK!

I did this two more times. 

Last time I reversed out, didn't start the bike, just wheeled it out and started it with the bars straight. And then a chicky babe pulled out ahead of me on a scoot. F*ck, I'll show her.

Bike was normal, I didn't show her anything. 

Thanks for that Iain, I thought I was up for big $$$$ to repair it. 

[Jukie]

This happen to both Mine and Betty too, so don't worry about it, not sure why but big know it all he is a legend

[dragonworld.]

Yep, my DS does zaklee the same thing!! Obviously some japanese saboteur at the Duc factory is routing the cables the wrong way to give us Ducatisti a heart attack [moto]

[CairnsDuc]

Could it also be a sign the Cable needs a bit of a lube/clean?

[mattyvas]

Just to chime in and re-enforce the story.
Had the same thing in the first few months of ownership.
Mine didn't hit 5k but it did rise considerably with the bars turned to the left.

[bigiain]

Question then: How many of you people who's seen this problem are running stock bars? When I looked at Melvins, I assumed the clipons had something to do with it - that there _was_ a "correct" cable routing that wouldn't exhibit this problem, but that when he got the clipons fitted the new routing was a little too tight. Is this also happening with stock, factory delivered bikes?

curious-big

[mattyvas]

Yeah it happened to my bike with stock bars as well as the Rizoma bars.

[Jukie]

and you known Jukie is stock or was and it still happens

[Betty]

and you known Jukie is stock or was and it still happens

.... well not really.

My bike is stock (but grips are not) and I can't say I have paid much attention, if it happens it is not dramatic - but the Boss tells me it happens.

Jukie, however, has the Rizoma fat bar and risers, but the forks have also being raised through the triple - providing something like a stock setup but with lots of variables. This is the bike we notice it on most (when backing up and turning to the left). It is not as dramatic as Super is experiencing but you can definitely hear the difference through those stock pipes.

Haven't monitored the change in revs as the bike is normally on the fast idle when it happens and I am backing it out down a hill so my attention is elsewhere.

[CairnsDuc]

OEM handlebars and speedymoto risers, The only time my revs rise is when the fast idle lever is on and I turn the Handle hard to the left.

It adds about 500 - 1000 revs depending on how far I have the lever back.

[goldFiSh]

Question then: How many of you people who's seen this problem are running stock bars? When I looked at Melvins, I assumed the clipons had something to do with it - that there _was_ a "correct" cable routing that wouldn't exhibit this problem, but that when he got the clipons fitted the new routing was a little too tight. Is this also happening with stock, factory delivered bikes?

curious-big

everything on my front end is stock, and I have not problems..

I think you're onto it big... new handlebars, clipons, addition of risers, all of these could all culprits..
I remember when I put on Rizoma grips, there were issues with the throttle cable sticking and some mods were required (this was well documented on TOB) so maybe that as well.