1150 Misfire - 2002 single spark

[clivewhilde]

Recently done a trip to the Sachesenring, washed the bike a week later, 2 weeks later (today) take a trip to Sheffield from Halifax. Bike performed faultlessly in Germany but now has developed an intermittent misfire.
It feels like its running out of fuel, it seems especially bad at small throttle openings and then goes away. There is a bit more popping on the overrun but nothing else I can see.
It stalled on the drive then reluctantly started, tickover a bit rough.

It was serviced before the German trip, new plugs etc.

Any pertinant advice greatly received.

 

[MattW]

Aside from the usual throttle cable seating check, my best guess would be coil or hall sensor - did it get very hot on your German trip?

 

[clivewhilde]

Aside from the usual throttle cable seating check, my best guess would be coil or hall sensor - did it get very hot on your German trip?

Presuming you mean the bike and not the weather (though that was very hot), it ran at 5 bars the whole trip except for a bit of flat out Autobahn when it got up to 6 bars but did several hundred km after that and all was well......

So I guess the answer is replace the items you suggest one at a time starting with the cheapest!!! Since i intend to keepmthe bike I guess they'll always come in handy. Motorworks?

 

[MattW]

Presuming you mean the bike and not the weather (though that was very hot), it ran at 5 bars the whole trip except for a bit of flat out Autobahn when it got up to 6 bars but did several hundred km after that and all was well......

So I guess the answer is replace the items you suggest one at a time starting with the cheapest!!! Since i intend to keepmthe bike I guess they'll always come in handy. Motorworks?

I'd wait for some more replies before rushing ahead and buying parts on my say so There may be some tests you can do to try and isolate the problem.

I think Motorworks will let you return used parts if you're fault finding or perhaps someone on here can lend you a coil?

I'd start with basic checks first - e.g are the valve clearances good, air filter ok, plugs a good colour and throttle bodies balanced? You could also try a compression check to rule out a burnt valve (after checking valve clearances).

 

[clivewhilde]

I'd wait for some more replies before rushing ahead and buying parts on my say so There may be some tests you can do to try and isolate the problem.

I think Motorworks will let you return used parts if you're fault finding or perhaps someone on here can lend you a coil?

I'd start with basic checks first - e.g are the valve clearances good, air filter ok, plugs a good colour and throttle bodies balanced? You could also try a compression check to rule out a burnt valve (after checking valve clearances).

Valve clearances and end float done before Germany, new plugs, K&N cleaned. Never balanced throttle bodies before, is there a sticky on how to on here?

 

[MattW]

Valve clearances and end float done before Germany, new plugs, K&N cleaned. Never balanced throttle bodies before, is there a sticky on how to on here?

I'm not sure about a how-to, but there's bound to be stuff - a search will probably throw up plenty of information.

This video covers using a home made manometer (I one like this):

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It would be worth pulling the plugs to check their colour - can give you hints about mixture. Similarly take a look at the air filter to check for any obvious blinding etc.

You have checked the seating of the throttle cables?

 

[clivewhilde]

I'm not sure about a how-to, but there's bound to be stuff - a search will probably throw up plenty of information.

This video covers using a home made manometer (I one like this):

<object width="480" height="385"><param name="movie" value="http://www.youtube.com/v/nEE508WzNC8?fs=1&hl=en_US"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/nEE508WzNC8?fs=1&hl=en_US" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="480" height="385"></embed></object>

It would be worth pulling the plugs to check their colour - can give you hints about mixture. Similarly take a look at the air filter to check for any obvious blinding etc.

You have checked the seating of the throttle cables?

Oh yes, most definitely - you can't get me that easily - how long have you been waiting to use that

 

[stavross]

missfire

water in fuel? try some wynns dry fuel. it worked on mine!

 

[Danny88]

this happened to my 1150 the other week i went for a ride the week before and it was perfect and then after a week of it being in the garage i started it up and stalled off the line, seemed to be running rough some how was hard to pin point it, it was like it was out of synchronization. anyway i waited until i finished the tank of fuel i had and replace it filling it all up. went to north wales over the weekend did 500 miles and it was perfect. maybe dodgy fuel, a bit of water in tank?

 

[clivewhilde]

this happened to my 1150 the other week i went for a ride the week before and it was perfect and then after a week of it being in the garage i started it up and stalled off the line, seemed to be running rough some how was hard to pin point it, it was like it was out of synchronization. anyway i waited until i finished the tank of fuel i had and replace it filling it all up. went to north wales over the weekend did 500 miles and it was perfect. maybe dodgy fuel, a bit of water in tank?

New fuel and some Wynns in the tank but the problem persists - thanks for the tip it was worth a try.

Went for a ride this morning, it seems to be OK cold but once warm the misfire starts, a few more pops and bangs than normal then if you shut the engine off, very difficult to restart.

Riding along in top it started missing but then wouldn't pick up again. Went down the box effectively bumping it but no joy coasted to a halt. I thought it was tow truck time but it re-started straight away.

Does this give any further clues

 

[DrFarkoff]

Do a search for hall effect sensor in this section and the font of all knowledge

Does your Revcounter jump around madly as it starts to run strangely?

 

[MattW]

New fuel and some Wynns in the tank but the problem persists - thanks for the tip it was worth a try.

Went for a ride this morning, it seems to be OK cold but once warm the misfire starts, a few more pops and bangs than normal then if you shut the engine off, very difficult to restart.

Riding along in top it started missing but then wouldn't pick up again. Went down the box effectively bumping it but no joy coasted to a halt. I thought it was tow truck time but it re-started straight away.

Does this give any further clues

It's still sounding like coil or hall sensor to me - my gut feeling would be hall sensor.
edit - Jaythro beat me to it

 

[Danny88]

whats a hall sensor? mine was doing this as you know and only when warm, could it be the lamber sensor not compensating the amount of fuel once it gets warm? when cold its running a little rich to warm the bike up and if the lamber is faulty maybe it's not registering it and not compensating the fuel amount, too much fuel going in not being burnt and thats why the popping in the exhaust?

Or am i just talking bollocks?

 

[Packer]

You can run without a Lambda sensor so try disconnecting it. Eliminates that. I'm not 100% certain but I believe that the Lambda only adjusts the mixture at higher revs anyway, it's ignored by the Motronic at tickover and when starting.

Check that the rubber caps for the vacuum points on the injector bodies are both there and not split.

Check that the throttle position sensor on th eleft throttle body isn't loose, may have been bashed during the cleaning routine.

Does th efuel pump sound noiser than usual?

If you used a pressure washer go bananas with WD40 at all the wiring connectors. Pull as many apart as you can find and make sure that they are dry and free of corrosion.

 

[davegs]

Hall sensor washing just a coincedence never wash it agin makes fault finding easier