Ducati Monster Forum

Moto Board => Tech => Topic started by: blueorb on May 17, 2011, 06:50:29 PM

Title: 2001 M900S ie - Gas Smell
Post by: blueorb on May 17, 2011, 06:50:29 PM
Hi all.

I recently purchased a 2001 M900S ie which has the Ducati performance package which consists of Duc Performance CF exhaust, open airbox with K & N filter and a Power Commander module. However, the PC is not connected and it is still running the stock ECU.

I am getting an odor of gasoline from the bike and the smell is definitely coming from the airbox.  I cleaned the air filter tonight and when I removed the filter I could smell the gas coming from the box. When I picked the bike up I did not notice the smell. The previous owner seems to think that the smell is due to me over filling the tank (with the bike standing straight up) and then  taking the bike home and parking it (tilted on the stand) which caused the gas to expand. The smell is from the gas venting. (The station is about 3 miles up the road. I filled up and brought the bike straight home).

Does anyone agree/disagree with this? I am assuming if that is what the smell is from it will go away onec the fuel level goes down?

Fyi...I have an appt this Thursday am for a dyno tune and to get the PC mapped (appt is with Lee's Performance here in Charlotte).

Thanks.
Title: Re: 2001 M900S ie - Gas Smell
Post by: ducpainter on May 17, 2011, 06:54:06 PM
How does it run?
Title: Re: 2001 M900S ie - Gas Smell
Post by: 2001cromo on May 17, 2011, 06:58:39 PM
2 most likely culprits would be

1)  drain lines inside the tank are not connected to the top cap

2) leaking tank hinge, you'd notice gas by the kickstand and front sprocket cover.


Nate, it was good to see you yesterday
Title: Re: 2001 M900S ie - Gas Smell
Post by: blueorb on May 17, 2011, 07:05:18 PM
The bike runs well. It is cold natured and takes a while to warm up after a cold start but other than that the only thing I have noticed is a popping during deceleration.  The bike runs great other than that.

I have checked all of the lines coming from the tank and they are all connected tightly and there are no leaks.  How does one go about checking for an line on the inside of the tank?
Title: Re: 2001 M900S ie - Gas Smell
Post by: speedknot on May 17, 2011, 10:03:56 PM
I have to same issue on my 01 M750.  Dont fret over it.  As long as its not dripping somewhere, I wouldn't worry about it.  Sometimes all I have to do is move my bike a bit and I smell it. 
Title: Re: 2001 M900S ie - Gas Smell
Post by: ducpainter on May 18, 2011, 05:29:29 AM
Quote from: blueorb on May 17, 2011, 07:05:18 PM
The bike runs well. It is cold natured and takes a while to warm up after a cold start but other than that the only thing I have noticed is a popping during deceleration.  The bike runs great other than that.

I have checked all of the lines coming from the tank and they are all connected tightly and there are no leaks.  How does one go about checking for an line on the inside of the tank?
If you open your gas cap you'll see two small holes. One on the left of the fill and one to the rear with a rubber 'fitting'. They are connected to the two small hoses on the bottom of the tank by a series of rubber hose and metal tubes inside. You can check the condition of the internal tubes by blowing air into those holes. If the air exits out the bottom hoses you're good to go. If you hear air inside the tank then one of the hoses inside either is damaged or has come off.

To access the inside you need to remove the piece the cap screws to.
Title: Re: 2001 M900S ie - Gas Smell
Post by: blueorb on May 18, 2011, 07:49:24 AM
Thanks for the replies every one.

Ducpainter - I will perform the test you described tonight. Will let you know how it goes.

as an update - I pulled the air filter last night and cleaned and oiled it.  The filter itself does not smell of gas. It is not wet with gas nor does it smell of gas. The smell is coming from inside the air box. When I pull the filter out there are two large holes/tubes that run down out of the air box (what are those anyway?).  The smell definitely seems to be coming from those tubes up into the air box.
Title: Re: 2001 M900S ie - Gas Smell
Post by: ducpainter on May 18, 2011, 08:07:20 AM
Those are your throttle bodies.
Title: Re: 2001 M900S ie - Gas Smell
Post by: blueorb on May 18, 2011, 08:37:06 AM
Hey Ducpainter,

I found this on webbikeworld and it sounds almost identical to what I am experiencing. However, it relates to a Ducati GT1000. Would my Monster also be susceptible to this?  If so, then this is definitely what has happened.

"By the way, don't overfill the GT1000 with fuel.  Enough room should be left in the top of the tank for expansion if the weather turns warm.  I filled the tank right up to the top once and left the bike in the garage, which became very hot one warm day.  An overpowering smell of gasoline hit me when I opened the garage and I traced it to the overflow.  The situation could have been disastrous, so use caution when filling the fuel tank."
Title: Re: 2001 M900S ie - Gas Smell
Post by: Speeddog on May 18, 2011, 08:44:08 AM
Yes, that could be the issue, it could have burped some gas out due to the tank being very full and then the gas expanding as it heated up.

Use caution when checking the vent and drain passages with compressed air, don't apply much pressure.
If a line is plugged, you can easily burst the thin hose that's inside the tank.
Title: Re: 2001 M900S ie - Gas Smell
Post by: ducpainter on May 18, 2011, 10:58:20 AM
If you overfill and the fuel expands enough to overflow it ends up either in the vapor cannister, if you still have one, or on the floor if you don't.

Since the vapor cannister is connected to the manifolds you might smell fuel in the airbox.

Usually the charcoal absorbs the vapor when it isn't running . If you overfill enough to put a bunch of liquid in the cannister and saturate the charcoal the bikes usually don't run very well afterward.
Title: Re: 2001 M900S ie - Gas Smell
Post by: blueorb on May 18, 2011, 07:02:59 PM
Just a little update. Took the bike out for a good ride tonight. Rode for about 44 miles so I burned a little more than a gallon of the fuel.  Bike has been parked for about 4.5 hours now. I still have the gas smell coming from air box area. Doesn't seem to be as bad but is definitely still there.
I have my dyno/tune appt tomorrow morning so hopefully this will not stop them from doing the tune/PCIII mapping.  Will do the air test on the tubes on the inside of the tank this weekend. 
Title: Re: 2001 M900S ie - Gas Smell
Post by: blueorb on May 19, 2011, 05:41:54 PM
Ok, so the drama continues.  Had the dyno appt today. Baseline run hade me at 85 HP. Not bad. The tuner did note that the bike is running pretty lean. Also, the dyno was picking up intermittent drops throughout the RPM range (you could see little "v" shaped drops in the graph).  The bike was NOT doing this before we connected the PC III. So, we disconnected the PC III and thee fluctuations stopped. Defective PC III.   It was out of warranty so I had to order a new one which comes next week with another dyno tune on Thursday.

- note....we also installed the high performance ECU that came with the package. However, my understanding is that the only that ECU does is raise the rev limiter to 9500 rpms (please correct me if I am wrong).

Now, I am having another problem. Between 1st and 3rd gears when trying to maintain a low rate of speed (ie..35-45 mph) the pike is skipping or hiccuping or surging (not sure what to call it).  It only does it in those gears and between 3000 and 4500 rpms.  When I give WOT or get in higher RPM's the bike runs very smoothly.  This was NOT happening prior to installing the high performace ECU.  The spark plugs are literally 2 weeks old (NGK's).  

So, what could be causing the skipping/hiccups at low RPM's?  Could swapping ECU have caused that? Should I replace it with the original until next week's dyno? Could the bike running so lean be causing this issue? If so, why is it happening all of a sudden?

Should I bother pulling the plugs? I do not have any crush washers. Can I reuse the ones that are there?

Sorry for all the questions. Thanks guys...
Title: Re: 2001 M900S ie - Gas Smell
Post by: Speeddog on May 19, 2011, 09:54:42 PM
If I understand correctly...

Bike ran fine with OEM ECU.
Bike runs poorly with high performance ECU.

I'd swap back to the OEM ECU.
Title: Re: 2001 M900S ie - Gas Smell
Post by: blueorb on May 20, 2011, 05:59:39 AM
Quote from: Speeddog on May 19, 2011, 09:54:42 PM
If I understand correctly...

Bike ran fine with OEM ECU.
Bike runs poorly with high performance ECU.

I'd swap back to the OEM ECU.

LOL, that about sums it up well.  After thinking about it I went ahead and put the stock ECU back in last night. Didn't get a chance to ride it. Will do so tomorrow and see what change, if any, it makes.
Title: Re: 2001 M900S ie - Gas Smell
Post by: blueorb on May 20, 2011, 06:35:53 PM
Well, I put the ECU back in and the surging/hiccup or whatever you call it went away. Obviously the high perfromance ECU does more than just raise the rev limiter.  Took the bike for a ride and it rode smooth as silk.  So, I guess that will be what I do for the dyno tune next week. Put the PC III in with the stock ECU and have it tuned that way.