Ducati Monster Forum

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.  ;)

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?

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?

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.


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. ;D

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

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

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

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] [laugh]

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

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.

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

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

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.

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.

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.

Yep wise to take a look at the cable routing, seems like all the cables and lines on mine are "just" long enough, had to do a bit of fiddling when I put the bar risers on, cut a few cable ties and spin the banjo fittings to get some slack in the lines and cables.
On bike cables and lines when it comes to securing them with ties etc less is more, as the cables need to move freely around the front triple and tight radius bends will give you grief as well.
Also in the olden days a bit of cable lube down the cables would help too.
Apologies if this sounds patronising but this also goes back to the old KISS system, check the simple things first before leaping to conclusions about checking and or replacing more complicated (and expensive) items.

YEP, Happens to me when I turn hard left - only a 100-200rpm. Everything is OEM on my bike. I noticed it a few months back, but just let it go as I did not think it would be a problem. Might have a look at the cable routing before the ride on Saturday.

Yeah, thanks.  [roll]

I didn't think now, DID I!

I did however do some research before posting, about a weeks worth before posting and even noticed the revs going up when the bars were straight. That was after making a hard left I realised later. The bike has been a little temperamental lately and I just thought the worst.

Right Brimo, how about I change the thread title.  ;)


 [cheeky]

Maybe take your baby back to Frasers & say their repair work has buggered up your bike.

Just out of interest: had you noticed it before your 'incidient'?

From what I can remember, I don't think I noticed it.

When I initially put the SM bars on, routing the cable/s was a pain in the arse, but it was only the brake line that was giving me grief (I think). I didn't want to loosen the banjo and have brake fluid dripping everywhere so I just persisted and managed to route the line around the cluster.

I'll see if I've got a pic of when I first installed the SM bars and what it looks like now.

There have been three times, in the entire life of the bike, where my S2R1k (with stock bars and a properly adjusted throttle cable - i.e. with the right amount of free-play at both the butterfly and the grip ends) will shoot up to nearly 3k. All three times that it has happened is when the bike has decided to surge like a bastard when sitting at the traffic lights, so I shut it off then restart. About 10 seconds after that, for which time it has idled at the factory proper 1200 rpm, it'll rev up to nearly 3k for about 5-10 seconds, then drop back and idle a bit low. Have not experienced since I unplugged the O2 sensor, oh, about 9000 km ago.

Switching the bike off and on stops the surging cause it puts it into start mode & ignores the sensor enough that it doesn't get cranky, but obviously it decides it needs to try the full range of the idle stepper motor, without actually bothering to try anything intermediate...

Well sorry, no offence meant, seems like I'm doin' well at pissing a few people off today, that said, my comment was meant generally, not to you specifically. As a service tech, I fix broken shit every day and have been guilty of breaking that same  golden rule myself so let's have a beer and make up.  [drink]

Just joking with ya Brimo, I know what you meant.  ;)

A little update,

I had a look yesterday and noticed the fast idle cable was up over the instrument cluster bolt.

I pushed it back down in front of the cluster and what do you know, doesn't happen anymore.

But it keeps snaking it's way back up so will have to cable tie it down.

On the swinging around of the banjo fittings idea, you can loosen them off a bit and move them around, the seal will keep the fluid in as it's not under pressure at the time. You can keep a rag handy just in case.

mr s4r exhibited the symptoms described by super, and after adjusting the cable, and lubing it and making sure the bars didn't tug or foul the cable and the throttle returned after a twist, my dealer pulled the TPS and replaced it and the problem was gone. it was a while ago so the exact details are a bit vague but i remember the tech pulling it apart and there was a spring steel coil inside, like the old temp operated choke on old webers. and that was binding up causing it to "stick".


paul