Hi, First thank's for the helpfull forum... Great help for the likes of me.
I just bougt a 99" "s, veryyyy nice, only one problem. When it is cold no problem, but as soon as it warms up...... Does not idle, misses, even backfire's, if it does idle it's very uneven and stalls. I installed new air filter (OEM), new plugs, set the valves, did a TB synch. Every thing seems fine. At below 2800 rpm, stutters and surges....above that...goes like a rocket. Fuel consumption is not half bad. 18km/ Liter. Please any help or ideas would be welcome.
Thank's Joel....
Help Please !!!
Moderators: slparry, Gromit, Paul
Had a similar problem with my former bike (F650CS) and it sorted itself out.Thanks.....I did the reset...(By pulling No4 fuse on righthand fuse box)
No Joy there either. I cleaned all the harnass connectors. (Got some serious corrotion there) The clock read 4800km, i forgot to mention in my previous post. I did not do a rocker arm end plate adjustment. There seem to be a ticking ? when the motor is hot. The valves are set correctly (Me think) inlet .15mm and ex .30mm. using two feeler gauges.
Thanks
Joel
No Joy there either. I cleaned all the harnass connectors. (Got some serious corrotion there) The clock read 4800km, i forgot to mention in my previous post. I did not do a rocker arm end plate adjustment. There seem to be a ticking ? when the motor is hot. The valves are set correctly (Me think) inlet .15mm and ex .30mm. using two feeler gauges.
Thanks
Joel
Hi Joel - You have't had the battery disconnected have you? The only thing I can think of is that the TPS needs resetting maybe? Just a thought. I'm sure others will correct me but I think if you disconnet the battery, then after reconnecting, with the ignition on, open the throttle wide open twice before starting it - I THINK that resets the TPS anyway. If you want to 'try before you buy' any expensive electronic bits I could send you a selection of bits from the wrecked S in the garage that you could plug and play to see if they make any difference befoew giving large amounts of cash to a BM dealer. I'll not be around till after 20th Sept after Tuesday though.
Jason
Jason
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Boxadog 2000
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Thanks Jason..
I adjusted the TPS by the zero to Zero method..and tried various other settings on it. From about .300v to .500v, resetting the motronic everytime.I don't know if it could be the TPS. What is strange is that the problem only start once the bike is hot...when it is cold it idles perfect...
On the other hand the problem only occurs where the TPS is suppose to control the works....(Me think....)
I don't know enough about the Motronic to start fiddling there...This is my first BM...I'm used to Rice burners......
Thanks...
Joel..
I adjusted the TPS by the zero to Zero method..and tried various other settings on it. From about .300v to .500v, resetting the motronic everytime.I don't know if it could be the TPS. What is strange is that the problem only start once the bike is hot...when it is cold it idles perfect...
On the other hand the problem only occurs where the TPS is suppose to control the works....(Me think....)
I don't know enough about the Motronic to start fiddling there...This is my first BM...I'm used to Rice burners......
Thanks...
Joel..
I'm sure you're a lot more handy with the electronics than me Joel so I don't know what else to suggest - could try removing the lambda from the exhaust and see if that makes any difference that might lead you towards a conclusion. Could it be a fuel pressure/blockage problem? I think Bailey had some sort of fuel starvation he reckoned was a blocked filter - Could it be a faulty HT lead/conection? I've had that sort or low rev behaviour on a car with a faulty HT lead. Did you change the plugs BEFORE or after the problem? I'm really just clutching at straws though - sorry!Joel wrote:Thanks Jason..
I adjusted the TPS by the zero to Zero method..and tried various other settings on it. From about .300v to .500v, resetting the motronic everytime.I don't know if it could be the TPS. What is strange is that the problem only start once the bike is hot...when it is cold it idles perfect...
On the other hand the problem only occurs where the TPS is suppose to control the works....(Me think....)
I don't know enough about the Motronic to start fiddling there...This is my first BM...I'm used to Rice burners......
Thanks...
Joel..
Good Luck
Jason
Hi Jason...
I replaced the plugs becuase of the problem.....The HT leads makes sence as on is chafed a bit....I taped it pretty good, it is on my replacement list. The Co and Lamda censors still need to be checked.....I was thinking of removing the lamda but don't know what impact it would have on the settings...On the outher hand was thinking of removing the whole Cat system. Here in South Africa we don't the stringent emmission control that applies over there..The Cat sounds a bit fishy, when you drive on rough surface it sounds like a shaking metal in a tin can...I did clean all the connectors to the Motronic, the lmda and the Co censors....This week i'm doing a stint in the Army (Only for the week though)...Next week i'm going to strip the bike, Covers , tank and so forth, and then start to check the whole electrial system....Some of the wires seem to be chafed....
But like with all things close to heart it still need a little TLC.....
Thanks for the help ....
This board is tops....
Thanks Joel...
I replaced the plugs becuase of the problem.....The HT leads makes sence as on is chafed a bit....I taped it pretty good, it is on my replacement list. The Co and Lamda censors still need to be checked.....I was thinking of removing the lamda but don't know what impact it would have on the settings...On the outher hand was thinking of removing the whole Cat system. Here in South Africa we don't the stringent emmission control that applies over there..The Cat sounds a bit fishy, when you drive on rough surface it sounds like a shaking metal in a tin can...I did clean all the connectors to the Motronic, the lmda and the Co censors....This week i'm doing a stint in the Army (Only for the week though)...Next week i'm going to strip the bike, Covers , tank and so forth, and then start to check the whole electrial system....Some of the wires seem to be chafed....
But like with all things close to heart it still need a little TLC.....
Thanks for the help ....
This board is tops....
Thanks Joel...
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stempy
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Well if it backfires that would indicate that fuel is getting through. There have been problems with the hall sensor on the front of the engine. It's the magnetic pick up device for the ignition and injection timing under the front plastic cover. Also the air bypass valves can bung up. It might be worth unscrewing the brass screws and giving it a good old clean up.
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Boxadog 2000
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Wet test.
Get a compression tester
From cold test left and right compression note values.
From hot remove plugs squirt a good shot of oil down plug holes measure compression note values.
If values are significantly different on hot/wet test could be dodgy valve seat/cracked/damaged head.
Note measured values can be up to 10% different this is ok over 10% and I would do some more investigation.
Bob
Get a compression tester
From cold test left and right compression note values.
From hot remove plugs squirt a good shot of oil down plug holes measure compression note values.
If values are significantly different on hot/wet test could be dodgy valve seat/cracked/damaged head.
Note measured values can be up to 10% different this is ok over 10% and I would do some more investigation.
Bob
misfire when hot
Having read this lot, wonderful thorough technical info!
Have you checked the basics? Spark is probably o.k. as it does run. Weak coils/points/igniters usually show up under load more than at tick over, or dont work at all. Have you got a bird's nest stuck in the air intake - checked the air filter? Would make it run rich & give you those symptoms. Or, is there an air leak somewhere on the intake system? Or gummed injectors? Or fuel starvation - less likely. Large throttle usually hides minor problems!
Have you checked the basics? Spark is probably o.k. as it does run. Weak coils/points/igniters usually show up under load more than at tick over, or dont work at all. Have you got a bird's nest stuck in the air intake - checked the air filter? Would make it run rich & give you those symptoms. Or, is there an air leak somewhere on the intake system? Or gummed injectors? Or fuel starvation - less likely. Large throttle usually hides minor problems!
Oyster. 1999 R1100S. Almost original.
Hi Oyster..
Thanks for the input...The TB's are coming of in the morning, to do a visual check. The Brass screws had a lot of muck on them, looked like a type of dry soot. Cleaned that off...I did instal a new (OEM) air filter element, found some fluid (water/oil mix, more water than oil) in the the intake box. Also found that the ends of the intake ducts that are ( me think) are supposed to be flared, are broken in two places. In other words they are not round anymore. Was thinking to just file them down to form a circle again...and improve the airflow...The injectors was not checked yet...will do that after i done with the TB's..At the moment there is about two turns differance between the left and right brass screws, (to get the TB's to sinch...) so it could be that there are an air leak somewhere...but would it only show up once the moteor is hot..?
Thanks for the input....outside perspective always helps...
Thanks
Joel
Thanks for the input...The TB's are coming of in the morning, to do a visual check. The Brass screws had a lot of muck on them, looked like a type of dry soot. Cleaned that off...I did instal a new (OEM) air filter element, found some fluid (water/oil mix, more water than oil) in the the intake box. Also found that the ends of the intake ducts that are ( me think) are supposed to be flared, are broken in two places. In other words they are not round anymore. Was thinking to just file them down to form a circle again...and improve the airflow...The injectors was not checked yet...will do that after i done with the TB's..At the moment there is about two turns differance between the left and right brass screws, (to get the TB's to sinch...) so it could be that there are an air leak somewhere...but would it only show up once the moteor is hot..?
Thanks for the input....outside perspective always helps...
Thanks
Joel
No problem Joel- either send me a PM or you can get me at jason@compers.demon.co.uk. Make it quick though mate - I'm only here tomorrow then off till 20thJoel wrote:Hi Jason..
May i e-mail You.....
or i could post my e-mail and just reply to your mail....
Thanks
Joel
Jason