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2004 R1150RT pings when it's hot outside

buckeyebill

New member
My 1150RT pings when the engine is hot and the air temp outside is over approx. 75degrees F . I purchased an aftermarket add on for the temperature sensor to lower the sensor temperature to the computer which has helped some but not cured the problem . Is my computer leaning out the fuel mix excessively as the temperature increases or is there another root cause to this problem ?
 
They do lean it out nowadays, so your educated guess might be true.
What brand and octane gas are you using? Does it go away with a major brand highest octance fuel?
 
It's possible that your throttle position sensor is not set correctly, especially the Zero setting at Fully-Closed throttle. See http://www.ibmwr.org/r-tech/oilheads/ If the Zero is not right, the whole scaling of the voltage fed to the computer versus actual throttle opening is thrown off.
Other than that, there's not much one can do besides add an after-market enrichener to fake out what the computer tells the injectors to do. Search for Roger04s posts about what works and how to do it, but double-check your TPS first.
Besides possible cheapass gas, maybe a different set of plugs? Mine used to ping once in a while with Bosch plugs, but with NGKs, it's pretty rare.

Addendum: If your valves are set too tightly, that will also increase the operating temperature. Set 'em a little "sloppy".
 
They do lean it out nowadays, so your educated guess might be true.
What brand and octane gas are you using? Does it go away with a major brand highest octance fuel?

I have used octane additives and every brand of gas under the sun. It is really just outside air temp that triggers the pinging. I can hear it getting more fuel by the engine tone on a cool day and I can jump on the throttle with no issues .
;)
 
It's possible that your throttle position sensor is not set correctly, especially the Zero setting at Fully-Closed throttle. See http://www.ibmwr.org/r-tech/oilheads/ If the Zero is not right, the whole scaling of the voltage fed to the computer versus actual throttle opening is thrown off.
Other than that, there's not much one can do besides add an after-market enrichener to fake out what the computer tells the injectors to do. Search for Roger04s posts about what works and how to do it, but double-check your TPS first.
Besides possible cheapass gas, maybe a different set of plugs? Mine used to ping once in a while with Bosch plugs, but with NGKs, it's pretty rare.

Addendum: If your valves are set too tightly, that will also increase the operating temperature. Set 'em a little "sloppy".

......I definitely did not set the valves on the sloppy side.....thanks for the other suggestions
 
Since new my '04 GS pinged on acceleration during really hot weather (ie, >90 degrees), especially when going up a hill. Nothing I did seemed to help until I upgraded the left side cam chain tensioner to the newer version. After that it has never pinged since. After the replacement I intentionally allowed my rpms to drop to 2000 during a really hot day (upper 90s) and then cracked open the throttle- no pinging.
 
How many miles?

The first thing to check is ignition timing. Some folks turn the igniter plate to full advance.

Mine was full of carbon. Had 185 Psi compression on both sides at 130,000 miles.

Thick layer on top of the piston.

004-L.jpg


you can also see the ring ends were lined up. Bike was burning 1/2 quart 800 to 1,000 miles.

David
 
My 1150RT pings when the engine is hot and the air temp outside is over approx. 75degrees F . I purchased an aftermarket add on for the temperature sensor to lower the sensor temperature to the computer which has helped some but not cured the problem . Is my computer leaning out the fuel mix excessively as the temperature increases or is there another root cause to this problem ?

Your problem is not that the Motronic leans the fueling at higher ambient temperature. It strives to keep the mixture management the same at all air temperatures and barometric pressures. I suspect your bike is too close to pinging all the time and as it gets hotter out that pushes up the combustion temperature just enough to ping.

Does your bike have the pink coding plug installed? Is your o2 sensor connected and working? Do you own a GS-911? (If you did you could log data to a CSV file and is be happy to look at it. That would tell us if your o2 sensor is working and also if its running lean when it shouldn't be.)

I think I'd check the compression and the static timing. If the compression is high, you might have carbon build up like an earlier poster mentioned.

Another possibility is that your fuel system can't deliver enough volume at pressure. If you checked the amount of fuel tree turning to your tank at idle you could give fuel flow a clean bill of health, or not. Should be 2 liters per minute at idle.
 
It's possible that your throttle position sensor is not set correctly, especially the Zero setting at Fully-Closed throttle. See http://www.ibmwr.org/r-tech/oilheads/ If the Zero is not right, the whole scaling of the voltage fed to the computer versus actual throttle opening is thrown off.
Other than that, there's not much one can do besides add an after-market enrichener to fake out what the computer tells the injectors to do. Search for Roger04s posts about what works and how to do it, but double-check your TPS first.
Besides possible cheapass gas, maybe a different set of plugs? Mine used to ping once in a while with Bosch plugs, but with NGKs, it's pretty rare.

Addendum: If your valves are set too tightly, that will also increase the operating temperature. Set 'em a little "sloppy".[/QUOTE

Re: IBMWR link
0=0 is for 1100's (Motronic Ma2.2) and does not apply to the 1150's (Ma2.4)
On 1150's you are better off setting the TPS with a GS911 - borrow one if you need to.
 
Sorry, but I must disagree - I have reset the TPS on a few 1150's using those instructions, and it's worked out quite well. Use a known good DVM with at least three decimal places of readout (to actually see the millivolts); one or two decimals won't suffice. I even have a little TPS harness extender jig to get on to the wire.

Roger & DRoot, thanks for the additional inputs; all good stuff. In the past, some shops had the habit of cranking up the advance plate, thinking that "the computer changes it anyway, and the available range [of the slots] isn't wide enough to hurt anything."

Another possibility is that the temperature sensor itself is bad - that would send an improper signal to the computer too. By the way, living where I do, I have made many desert crossings in the heat of the day... zero issues.
 
How many miles?

The first thing to check is ignition timing. Some folks turn the igniter plate to full advance.

Mine was full of carbon. Had 185 Psi compression on both sides at 130,000 miles.

Thick layer on top of the piston.

View attachment 40151


you can also see the ring ends were lined up. Bike was burning 1/2 quart 800 to 1,000 miles.

David

My RT has 50000 miles and has always burned about a quart every 1000 . Thanks for the input
 
Your problem is not that the Motronic leans the fueling at higher ambient temperature. It strives to keep the mixture management the same at all air temperatures and barometric pressures. I suspect your bike is too close to pinging all the time and as it gets hotter out that pushes up the combustion temperature just enough to ping.

Does your bike have the pink coding plug installed? Is your o2 sensor connected and working? Do you own a GS-911? (If you did you could log data to a CSV file and is be happy to look at it. That would tell us if your o2 sensor is working and also if its running lean when it shouldn't be.)

I think I'd check the compression and the static timing. If the compression is high, you might have carbon build up like an earlier poster mentioned.

Another possibility is that your fuel system can't deliver enough volume at pressure. If you checked the amount of fuel tree turning to your tank at idle you could give fuel flow a clean bill of health, or not. Should be 2 liters per minute at idle.

I have got to educate myself on the motronic . No idea what my coding plug is or if my oxygen sensor is working . Don't own a GS -911 . I have some work to do to get closer to this problem . Thanks for the inputs
 
Sorry, but I must disagree - I have reset the TPS on a few 1150's using those instructions, and it's worked out quite well. Use a known good DVM with at least three decimal places of readout (to actually see the millivolts); one or two decimals won't suffice. I even have a little TPS harness extender jig to get on to the wire.

Roger & DRoot, thanks for the additional inputs; all good stuff. In the past, some shops had the habit of cranking up the advance plate, thinking that "the computer changes it anyway, and the available range [of the slots] isn't wide enough to hurt anything."

Another possibility is that the temperature sensor itself is bad - that would send an improper signal to the computer too. By the way, living where I do, I have made many desert crossings in the heat of the day... zero issues.

Pauls1150, some good ideas here. A GS-911 would be helpful. A bad IAT sensor defaults to 25C and would cause a problem.

On the TPS voltage, the procedure you mention won't cause harm but may be overly precise and a bit off. The Motronics MA 2.2 (1100s) and MA 2.4 (1150s) each have a Motronic output that tells you when the TPS is adjusted best. The MA 2.2 signal can be seen with an LED on diagnostic Pin 3. The MA 2.4 must be read with a GS-911. It is important enough to the Motronic that it has a way to tell you when it is correct, no need for an anecdotal (DVM) method.

I have tried many times with shims and offsets to fool the MA 2.4 without success. That tells me it has a wide range of voltages that itmcanmwork with.
 
Pauls1150, some good ideas here. A GS-911 would be helpful. A bad IAT sensor defaults to 25C and would cause a problem.

On the TPS voltage, the procedure you mention won't cause harm but may be overly precise and a bit off. The Motronics MA 2.2 (1100s) and MA 2.4 (1150s) each have a Motronic output that tells you when the TPS is adjusted best. The MA 2.2 signal can be seen with an LED on diagnostic Pin 3. The MA 2.4 must be read with a GS-911. It is important enough to the Motronic that it has a way to tell you when it is correct, no need for an anecdotal (DVM) method.

I have tried many times with shims and offsets to fool the MA 2.4 without success. That tells me it has a wide range of voltages that itmcanmwork with.

Thanks Paul
 
Question - Why would it be "a bit off"? I don't have a GS-911, and on the bikes I've tweaked, the results were always either "improved", "improved just a little", or "no perceptible difference". Edumacate us - If I can do better, I certainly want to! Thanks!
 
Question - Why would it be "a bit off"? I don't have a GS-911, and on the bikes I've tweaked, the results were always either "improved", "improved just a little", or "no perceptible difference". Edumacate us - If I can do better, I certainly want to! Thanks!

This is just me being me. Your number is inside the range that works. Once it's in the range, it doesn't seem to matter much.

On my GS-911, it shows a range of acceptable voltages. It seems to me that the only way to know if you're in the center of your Motronic's range is with the Motronic output display--so that's the extent to which you could be "a bit off". The reality is, as I mentioned, that it is hard to do anything that the Motronic doesn't seem to take in stride on the 1150.

As you know the 1150 TPS has two pots in parallel one for up to the first 20 degrees or so (can't find the sheet). The sensitivity of the first pot is 0.025 degrees per 5mV so 30mV is 0.15 degrees. I think the GS-911 is satisfied somewhere between 300 and 400 mV.
 
If your valves are set too tightly, that will also increase the operating temperature. Set 'em a little "sloppy".

Setting the lash too tight (which I actually recommend - 2/3 of normal) effectively increases the "dwell" slightly, which effectively increases the compression ratio slightly. Which will lead to running a little hotter and more tendency to ping.
Someone may need to correct me, I believe the compression on the 1150 is already 11:1, pretty high.

Can you get 93 octane where you are?

Check the hall effect sensor (ignition timing) plate - it has about 3 degrees of adjustment and if it is maxed out it can be too much under load.

Spark plugs can be had in a lower heat range.
Normal Bosch plug would be FR6DDC - the 6 is the heat range (6 is pretty much in the middle).
You could drop to heat code 5 or 4 as an experiment.
I doubt this will make any difference unless you run wide open a lot.
 
Thanks, Roger.

Scott, having the valves "tight" also decreases the time that a closed valve spends on the valve seat. This reduces the transfer of heat from the valve to the head (more critical on the exhaust side), further increasing temperature.

And for those who haven't seen the inside of the 1150 TPS, here ya go; this one is at almost closed throttle. The 1100s had windings of resistance wire instead of the carbon resistive elements. It's a bit more than just resistors in parallel, it's a nonlinear voltage-divider network.
 

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