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#1000508 - 11/08/17 05:22 AM Engine dies when coming to a stop  
Joined: Apr 2017
Posts: 69
Imgnr Offline
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Imgnr  Offline
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Joined: Apr 2017
Posts: 69
Los Angeles
Hi All,

2004 Rockster here. Went for a first real trip a few weeks ago and the bike performed flawlessly. In SoCal so took the PCH down to the Ortega Highway then over the mountains to Palm Springs.

However, the engines's started to occasionally shut down when riding very slowly with the clutch in, either when I'm coming to a stop or coasting between traffic. Only when I'm about going about 5-10 mph.

I've done some research and turned up the big brass screw to two turns out which bumped the idle to about 1,500 rpm but it doesn't help. I've read that it could be the throttle position sensor or a number of other things.

Hoping that this is a commonly fixed problem as it's a little scary trying to restart the engine in the middle of traffic.

Thank you!


No sparkenzie BMW but learning...
#1000515 - 11/08/17 11:38 AM Re: Engine dies when coming to a stop [Re: Imgnr]  
Joined: Jun 2010
Posts: 13,270
dirtrider Offline
The Oracle
dirtrider  Offline
The Oracle
Member

Joined: Jun 2010
Posts: 13,270
Ohio
Originally Posted by Imgnr
Hi All,

2004 Rockster here. Went for a first real trip a few weeks ago and the bike performed flawlessly. In SoCal so took the PCH down to the Ortega Highway then over the mountains to Palm Springs.

However, the engines's started to occasionally shut down when riding very slowly with the clutch in, either when I'm coming to a stop or coasting between traffic. Only when I'm about going about 5-10 mph.

I've done some research and turned up the big brass screw to two turns out which bumped the idle to about 1,500 rpm but it doesn't help. I've read that it could be the throttle position sensor or a number of other things.

Hoping that this is a commonly fixed problem as it's a little scary trying to restart the engine in the middle of traffic.

Thank you!


Morning Imgnr

Stalling on dropped throttle isn't very common & could be difficult to find without a LOT more specific info from you about the problem.

So give us as much info about the problem as you can (everything that you can think of).

Does it ALWAYS stall at dropped throttle while costing or just on this one ride over the mountains?

Has it done it since you are home?

Did the problem start after you re-fueled the bike?

Any whooshing from the fuel filler cap when you open it after a long ride?

Did you do a new TPS re-learn after the last time you had a dead battery or disconnected the battery?

We can't ride the bike so all we have to work with is your observations over the internet. The more accurate & complete your information
about the stalling the more accurate our help will be.

Added: you might start by looking at your o2 sensor wire pig tail to make sure it isn't hanging down or contacting the hot exhaust system. I have seen
some stalling issues due to o2 problems or o2 wire pig tail contacting the exhaust.

Also, does your bike have the correct CCP in it?



Last edited by dirtrider; 11/08/17 12:26 PM.

D.R. ___
Sent from my rotory dial wall phone!
#1001750 - 12/01/17 04:15 AM Re: Engine dies when coming to a stop [Re: Imgnr]  
Joined: Apr 2017
Posts: 69
Imgnr Offline
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Imgnr  Offline
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Joined: Apr 2017
Posts: 69
Los Angeles
Sorry for the long lapse. I wanted to see if my "fix" will work first before posting. I think my poor city fuel mileage and low speed stalling has to do with the cat eliminator and after-market pipe not creating enough back pressure so I ordered an oem pipe from e-Bay. I was flummoxed when I put the exhaust and it wasn't compatible with the exhaust. Seems the PO had the mid pipe custom made. Wasted some good money for nothing.

Anyhow, I started altering the way I ride by 1) not "burbling" to a stop by keeping the bike in high gear and running the rpms really low and pulling in the clutch. I guess that's a lazy way to ride. I downshift when required and pull in the clutch when I'm down in the first gear and 2) keep the throttle just very slightly higher (around 2k rpm) right before I come to a stop. It's only stalled once or twice since I started riding this way.

Any thoughts on my riding style and why it was stalling would be appreciated.


No sparkenzie BMW but learning...
#1001762 - 12/01/17 01:08 PM Re: Engine dies when coming to a stop [Re: Imgnr]  
Joined: Jun 2010
Posts: 13,270
dirtrider Offline
The Oracle
dirtrider  Offline
The Oracle
Member

Joined: Jun 2010
Posts: 13,270
Ohio
Originally Posted by Imgnr
Sorry for the long lapse. I wanted to see if my "fix" will work first before posting. I think my poor city fuel mileage and low speed stalling has to do with the cat eliminator and after-market pipe not creating enough back pressure so I ordered an oem pipe from e-Bay. I was flummoxed when I put the exhaust and it wasn't compatible with the exhaust. Seems the PO had the mid pipe custom made. Wasted some good money for nothing.

Anyhow, I started altering the way I ride by 1) not "burbling" to a stop by keeping the bike in high gear and running the rpms really low and pulling in the clutch. I guess that's a lazy way to ride. I downshift when required and pull in the clutch when I'm down in the first gear and 2) keep the throttle just very slightly higher (around 2k rpm) right before I come to a stop. It's only stalled once or twice since I started riding this way.

Any thoughts on my riding style and why it was stalling would be appreciated.


Morning Imgn

My personal thought is:-- Don't alter your riding style to keep from stalling but repair the bike so it operates correctly & won't stall.


D.R. ___
Sent from my rotory dial wall phone!
#1001763 - 12/01/17 01:47 PM Re: Engine dies when coming to a stop [Re: dirtrider]  
Joined: Apr 2015
Posts: 39
Cap Offline
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Cap  Offline
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Fort Collins, CO
Originally Posted by dirtrider
Don't alter your riding style to keep from stalling but repair the bike so it operates correctly & won't stall.


Ditto that. Your bike runs OK when you have the throttle open, and stalls when the throttle is closed. The fact that it runs OK when the throttle is open rules out a lot of potential problems. The 2004 model is a dual-spark. You might have a bad stick-coil. Or, maybe your TB's are way out of balance. Or, your throttle cables are badly adjusted.

Engines are not that complicated... fuel, air, spark. Figure out which one of those is different at closed throttle vs. open throttle. Probably not fuel pressure because your electric fuel pump operates independently of throttle position.

Spark? Checking a stick coil is easy. When the bike is running (hold the throttle open somewhat if you need to) unlatch the connector at the base of the stick coil. If the bike runs the same when you remove the coil, then the coil is bad. Check that first.

If the coils are good, then you have an air imbalance at low throttle openings. Try a simple TB balance and throttle-cable adjustment. If that doesn't cure it, then you might look at the TPS calibration next.

#1001764 - 12/01/17 02:07 PM Re: Engine dies when coming to a stop [Re: Imgnr]  
Joined: Nov 2002
Posts: 4,783
AndyS Online
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AndyS  Online
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Somerset, Great Britain.
Have you done a full service on the bike?
If not, do one. That way you have a better point of reference for any further fault diagnosis. There are a fair few things that can screw with the engine, so let's eliminate the obvious.

#1001774 - 12/01/17 08:09 PM Re: Engine dies when coming to a stop [Re: Imgnr]  
Joined: Jan 2015
Posts: 85
Shane J. Offline
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Shane J.  Offline
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Joined: Jan 2015
Posts: 85
Olympia, WA
I had a similar problem that I chased until I finally found an intermittent fault with a stick coil. It would frequently die at an idle when the problem was there, run fine other times. And it would run ok above 3 grand. After finally replacing the stick coils with brand new ones, the problem disappeared and the high speed performance is amazingly better. So, since it is one of the easiest to check I would eliminate it as the source first. I was too quick to pass an ok diagnosis on the sticks. If I had been more proactive I could have saved myself a lot of aggravation.


Shane J.
Tumwater WA

2006 R1150RTP, 2004 R1150RT (my wife's bike), 1995 Buell S2 Thunderbolt
prior bikes,1969 BSA 650, 1994 Sportster, 1996 FLHS, 1999 Buell S3, 2002 Buell S3, 2003 BMW R1150 RTP
#1001784 - 12/02/17 12:18 AM Re: Engine dies when coming to a stop [Re: Imgnr]  
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beemerman2k Offline
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beemerman2k  Offline
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Ellington, CT
This was happening on my '09 K1300GT, a very different engine than what you have. Nonetheless, the dealer updated the firmware on my fuel injection system and that solved the problem. No more stalling.


beemerman2k
'00 R1100RT Opal Blue Metallic
<11 year haitus from motorcycling cry >
'09 K1300GT U of Michigan Blue, baby! thumbsup
Defeat is my teacher, not my master - Bruce Lee
#1001966 - 12/05/17 12:30 AM Re: Engine dies when coming to a stop [Re: Imgnr]  
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cat0020 Offline
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cat0020  Offline
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Given that you've only recently completed a first "real" road trip, likely the bike is in need of a good maintenance.
Air filter, fuel filter, oil filter, spark plugs, throttle body balance even valve adjustments, all are easy to do on your own to get familiar with your Rockster.
If stalling problem still exist post maintenance, then I would look into the more difficult stuff.


Master your environment, and you will survive just fine.
Chances favor the prepared mind.

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