Ducati Monster Forum

Moto Board => Tech => Topic started by: greenohawk69 on March 10, 2012, 01:58:20 PM

Title: Engine runs faster when stopped
Post by: greenohawk69 on March 10, 2012, 01:58:20 PM
After I have run my bike ('97 M900) a bit and I come to a stoplight and sit...the engine will begin to run faster.  If I pull in the clutch it will slow back down.  I've also been in neutral and increased the choke and it will slow the engine down.  What may be causing the engine to run faster?
Title: Re: Engine runs faster when stopped
Post by: Speeddog on March 10, 2012, 02:23:16 PM
Year and model of Monster?
Title: Re: Engine runs faster when stopped
Post by: greenohawk69 on March 10, 2012, 06:40:47 PM
Quote from: Speeddog on March 10, 2012, 02:23:16 PM
Year and model of Monster?

'97 M900
Title: Re: Engine runs faster when stopped
Post by: JoeP on March 11, 2012, 04:09:51 AM
I had the same issue with my 01 M600. I checked for vacuum leaks and found none, so I turned the idle screw down 1/8 and that fixed it.
Title: Re: Engine runs faster when stopped
Post by: ducpainter on March 11, 2012, 06:03:31 AM
Quote from: greenohawk69 on March 10, 2012, 01:58:20 PM
After I have run my bike ('97 M900) a bit and I come to a stoplight and sit...the engine will begin to run faster.  If I pull in the clutch it will slow back down.  I've also been in neutral and increased the choke and it will slow the engine down.  What may be causing the engine to run faster?
It's either too high an idle or a synch issue.
Title: Re: Engine runs faster when stopped
Post by: greenohawk69 on March 11, 2012, 08:59:25 AM
Quote from: ducpainter on March 11, 2012, 06:03:31 AM
It's either too high an idle or a synch issue.

I'll check the idle.  I also checked for vacuum leaks - pulled off the airbox, looked over hoses for cracks and quality and any area where air might get in that it should not.  The carbs were synched by Houston Superbike in May 2011 which they stated they used a digital analyzer when looking over the carb.  Had a plugged fuel filter that was replaced then.  Just replaced the fuel filter again - could hear crap in it and cleaned out the area around the fuel cap.  Took it off cleaned off peeling paint in that area. 
Title: Re: Engine runs faster when stopped
Post by: ducpainter on March 11, 2012, 11:59:05 AM
Quote from: greenohawk69 on March 11, 2012, 08:59:25 AM
I'll check the idle.  I also checked for vacuum leaks - pulled off the airbox, looked over hoses for cracks and quality and any area where air might get in that it should not.  The carbs were synched by Houston Superbike in May 2011 which they stated they used a digital analyzer when looking over the carb.  Had a plugged fuel filter that was replaced then.  Just replaced the fuel filter again - could hear crap in it and cleaned out the area around the fuel cap.  Took it off cleaned off peeling paint in that area. 
carbs can go out of synch in a year...regardless of how good a job was done.

It is probably just an idle speed issue.
Title: Re: Engine runs faster when stopped
Post by: gatorgrizz27 on March 14, 2012, 02:39:49 PM
If it revs up around 2500 rpm once warm with the clutch in, but will drop back down if you ease the clutch out a bit it may be worn needles and seats as well.  They wear into oval shapes and let too much gas flow around the needle at idle, revving the engine up.
Title: Re: Engine runs faster when stopped
Post by: greenohawk69 on March 14, 2012, 07:27:02 PM
Adjusted the idle speed as suggested and it appears to have worked.  

Did not know where the idle adjuster was, but...used that weird thing called the "SEARCH" function and came upon a thread from 2010 that had a color picture of the bottom of the carbs with the Idle screw adjuster clearly marked!  Made it easy.  

Thanks for everyone's help.