Ducati Monster Forum

Moto Board => Tech => Topic started by: Clickjack on February 17, 2009, 11:22:43 PM

Title: Pulsing Motor
Post by: Clickjack on February 17, 2009, 11:22:43 PM
I know I have seen this either on this board or the old one, but I can't find it...

I have a 2007 S4R T.  I bought it new back in Sept, or Oct.  Due to circumstances out of my control I haven't been able to ride much, so It has 575 miles on it....   I noticed the other day while letting it warm up, the motor is pulsing.  Is this normal?  It's completely stock.
Title: Re: Pulsing Motor
Post by: Howie on February 18, 2009, 04:35:25 AM
What do you mean by "pulsing"?
Title: Re: Pulsing Motor
Post by: EEL on February 18, 2009, 07:00:11 AM
I'm guessing here since more info needs to be provided but you're experiencing an RPM fluctuation  while idling.

I've seen this when the throttle bodies need syncing or with a very loose set of valves. If you've messed w/ either lately, you've done something wrong. More common of the two throttle body tweak. If you messed w/ the set screw then this would be a common cause.

Throttle bodies need to be fully closed when idling. If they are a hair open, air will leak thru and cause this pulsing motor effect. Sometimes if its just a crack as the engine warms the leak seals itself as the metal expands and the problem goes away.



AGAIN...Just a guess.
Title: Re: Pulsing Motor
Post by: booger on February 18, 2009, 02:22:21 PM
Maybe getting out and riding the bike would be prudent, since it's around 2 years old and hasn't been broken in yet. Try a little BG or Techron in a full tank of fuel and run it all out. You might have a bit of stale gas giving you problems.
Title: Re: Pulsing Motor
Post by: Smokescreen on February 18, 2009, 04:25:16 PM
Three things...

1) What's the "T" stand for?
2) It's a v-twin, they do tend toward that kind of pulsing behaviour
3) +1 bergdoerfer...  Prolly you could dump a half bottle of Seafoam in there, top the tank off, and give her an Italian tune-up.  You know, burn off the whole tank riding the bike for approximately 2 hours and an average of 60 mph.  Ideally you do this in a setting you know won't stress out your bike.  Try a very twisty road with some straights thrown in where you can really pound on the gas, then downshift and allow for some engine braking.  It's what your bike wants...  It's what your bike needs...  It's called....  LOVE
Title: Re: Pulsing Motor
Post by: booger on February 18, 2009, 08:46:30 PM
Yeah just get out and ride it. It's probably nothing but a symptom of neglect. Do the Techron in a full tank thing, and then take it in for its 600 mile service. 575 miles on a 2 year old Testa head; that bike needs a surrogate rider. Seriously, just ride the bike.

It's a nice bike!
Title: Re: Pulsing Motor
Post by: Oldfisti on February 20, 2009, 08:52:42 AM
Quote from: Smokescreen on February 18, 2009, 04:25:16 PM
Three things...

1) What's the "T" stand for?



Testastretta