961 sensor thread

Fast Eddie

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I’d like to create a thread here to really understand the various (often troublesome) sensors on these bikes.

Off the top of my head, we have:

Crank position sensor

Head temp sensor

Air temp sensor

Oil pressure sensor

Throttle position sensor

Lamba sensors

What have I missed??

For each sensor, what are the common failures modes? And what are the symptoms thereof?

For each sensor, what does it actually do? Ie:
What is it reading for?
What is the NOK trigger point?
What signal is sent to where when it triggers NOK?
What is that signal used for?

(For example, the oil pressure sensor reads oil pressure at xxxx, it triggers NOK at X psi, it sends signal to oil pressure warning light that illuminates red. When oil pressure is returned, signal stops, light goes out).

Any knowledgable folk out there care to start us off...?
 
LAMDA SENSORS
When mine failed symptoms were, running very rich, cough & splutter below 30mph,bit like an old two stroke with the wrong jets in, very smelly exhaust,very juicy on fuel ( 80 miles & fuel light came on ). My bike is. 2016 mk2 euro3.
 
Crank position sensor - This one has caused us many issues.

Head temp sensor - This one is delicate and breaks easy if you're cleaning your bike and you twist it.

Air temp sensor - Only issue with this is the airbox design.
When riding in rain it drowns so make sure to use dielectric grease and try not to ride in the rain

Oil pressure sensor - No issues to report from us

Throttle position sensor- This is the sensor I wish I had when I rode out to North Carolina. This ruined half my trip there. There was a batch of these that were garbage. Even brand new ones replaced from the factory were garbage. On one bike we swapped it out twice with other customers brand new bikes trying to find one that worked.

Lamba sensors - We use those resistors and the issues go away.

Also add:
COIL - The factory ones used to be fake BOSCH. Get the real one and issues are gone.
 
I’d like to create a thread here to really understand the various (often troublesome) sensors on these bikes.

Off the top of my head, we have:

Crank position sensor

Head temp sensor

Air temp sensor

Oil pressure sensor

Throttle position sensor

Lamba sensors

What have I missed??

For each sensor, what are the common failures modes? And what are the symptoms thereof?

For each sensor, what does it actually do? Ie:
What is it reading for?
What is the NOK trigger point?
What signal is sent to where when it triggers NOK?
What is that signal used for?

(For example, the oil pressure sensor reads oil pressure at xxxx, it triggers NOK at X psi, it sends signal to oil pressure warning light that illuminates red. When oil pressure is returned, signal stops, light goes out).

Any knowledgable folk out there care to start us off...?

Is there also a cam/ speed sensor?
 
Oh for sure it has. Many problems.

Richard, is there some reason why you don’t wish to be more specific and answer the question posed “For each sensor, what are the common failures modes? And what are the symptoms thereof?” ?
 
Crank position sensor - This one has caused us many issues. Matt Capri shared with us he found many of them in the wrong position. So I guess I mis-typed here. Nothing wrong with the sensor it self. More the position of it or the screws being loose and needing tightening.

Head temp sensor - This one is delicate and breaks easy if you're cleaning your bike and you twist it. This is a combo of issues. In some of the bikes we've seen they use knock off sensors (fakes) that just simply burned them selves out because they were not up to par with such a hot environment. Others from human error. If you knock it or twist it you can break the internal connection. We played around with different sensors that showed to work faster or read more accurate but it had zero influence on the actual bike running or idling. And if there was a difference it wasn't worth it for the street.

Air temp sensor - Only issue with this is the airbox design.
When riding in rain it drowns so make sure to use dielectric grease and try not to ride in the rain. No known issues with the sensor itself causing any troubles. You do have to clean them with rubbing alcohol every once in a while because as they get dirty the give false readings. Not sure if it makes a huge difference but we notice after you clean it the bike seems better but nothing to calibrate if it really does anything.

Oil pressure sensor - No issues to report from us

Throttle position sensor- This is the sensor I wish I had when I rode out to North Carolina. This ruined half my trip there. There was a batch of these that were garbage. Even brand new ones replaced from the factory were garbage. On one bike we swapped it out twice with other customers brand new bikes trying to find one that worked. The main issue is flat spots. It cuts out fuel at the most frequently used areas of use. So when you do a very long trip (say 8+hrs) the sensor wears and make s flat spot in teh power. And if my dad and I swapped the error would move. Maybe because cable adjustments or riding style. We had enough of these fail for the first few years we stopped buying from Norton and sourced from a Mercedes dealer or distributor. I forget now. Any how, Norton must have got a better batch (could have been knock offs) as this really only seemed to affect 2013 and 2014 bikes. Because I haven't heard of this issue on any other years.

Lamba sensors - We use those resistors and the issues go away. I think the issue was more with the CATS clogging up internally. As we just discovered. But We have had so many issues with LAMBDA sensors on all years. Pull them out and use resistors. I'll never go back.

IGNITION COIL - The factory ones used to be fake BOSCH. Get the real one and issues are gone. Also et better wires. and use NGK Iridiums.

CAM SENSOR - So this one caused us issues on more than a couple bikes. It is the exact same sensor as the speed sensor. And also plays a part in a flat spot. We shared this with the factory and they sent me about 5 new sensors and I was able to label each sensor and move the flat spot around and also could repeat poor starting and poor idle by using a specific sensor. I believe the factory dealt with it and again, this was on 2014 bikes only. Since I found a good sensor (from factory) I've continued to use it with out any issues.

ECU - Might as well add this too. Ever since I started using the OMEX --- wow, night and day difference. Hence why we made the brackets as Norton didn't make them for single seat bikes. It's plug and play. Of course we can program ours ourselves, so if you can't, make sure to buy one pre-programmed for you set up.
 
Richard,

Thanks.

That is one comprehensive listing of potential sensor issues on these bikes.

Also, a great argument for conversion to carburetors.:p

FCR’s gotta have a lot fewer failure points, as well as other performance benefits.
 
Indeed BritTwit...

I was hoping we'd go deeper into this topic and actually understand what these sensors do, what the triggers are, what happens with the signals sent, etc.

One concern I have with carbs is that I wonder if the ECU is using the sensors to compensate and adjust when things get hot, or poor fuel is used, etc.

Carbs can't adjust, so would one of these engines be at risk if running carbs?

And... precisely what would we do with these sensors if fitting carbs? Disconnect, frig with resistors, leave alone, etc?
 
Pretty much every new bike and car has a list of sensors like that except they rarely give trouble ( Mazda 3 287,000 kms zero sensor problems)
Much of the shift to electronic engines was to do away with all of those carb problems we used to have, shitty cold running, sticky chokes, poor fuel mileage and less than stellar performance.

In my experience the electronic engines of today work.
You turn the key and they go, perfect running every time.
Sensors are incredibly reliable.
Why are so many dud sensors fitted to one machine with the Norton?
How on earth did they find them all?

Glen
 
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Indeed BritTwit...

I was hoping we'd go deeper into this topic and actually understand what these sensors do, what the triggers are, what happens with the signals sent, etc.

One concern I have with carbs is that I wonder if the ECU is using the sensors to compensate and adjust when things get hot, or poor fuel is used, etc.

Carbs can't adjust, so would one of these engines be at risk if running carbs?

And... precisely what would we do with these sensors if fitting carbs? Disconnect, frig with resistors, leave alone, etc?


If a carb conversion were done, I would cut out the ECU entirely, remove it.
Use the wiring harness/loom as a normal signal conduit as is the case on old carb-ed bikes.
Think the engine would be at no more risk from heat then any air cooled machine of the past, before EFI.
The carbs would have to be jetted properly to avoid detonation, or burned valves, etc.
But with dynos being commonly available today, this can be accomplished quite easily.

Use bad fuel with FCR's. You'll have to learn to work on them to flush and clean them.

After the conversion, I would carefully place the ECU, all sensors, throttle body, and fuel pump into a box for the next potential owner of the bike. In the unlikely event that he, or she (being open minded here) might wish to restore the bike to original condition.
Say, if the bike was going into a museum, and would not ever have to be actually started again.:p
 
Well , I wouldn't want to get rid of my EFI . It works pretty well and I like the fuel mileage I get. The only sensor I have actually had fail on my bike was the tip over sensor. We know how to troubleshoot this now and I have made an eliminator for troubleshooting it , which I posted a while back. My bike is running really well and I wish all 961 owners would have the same experience. The other sensors I replaced because I just wanted to make sure I had the best parts in there to hopefully avoid troubles. Is it ok to ask owners why they want to get rid of the EFI ? Is it the idle or what reason ??? There are solutions to most of this , as you guys have read about. We can make the SC Idle good man with NAIS ! And if you have the extra money to spend go for the new OMEX update . NOW , Why are the owners with the NEW 961's still having issues ? Not everyone of course , but it seems that Fast Eddie is the only trouble free machine ? I would hope that Norton could finally get the 961 sorted and reliable . Spend the the money Norton and get these bikes right for goodness sake .. !
 
The carbs would have to be jetted properly to avoid detonation, or burned valves, etc.
But with dynos being commonly available today, this can be accomplished quite easily.

Use bad fuel with FCR's. You'll have to learn to work on them to flush and clean them.

I’m not sure it’s quite that simple. For example, in modern high performance engines designed for high octane fuel, if you put low octane fuel in, you’ll lose a lot of power because the ECU does so on purpose to avoid detonation. At the least, it will alter ign timing and fueling. Some will limit revs, etc.

It’s the only way they can tune for max performance AND be safe.

Put carbs on an engine like that and you have to choose between being tuned for max performance OR safety. Can’t have both!

“Jetted properly” is another similar topic. “Properly” would normally mean an air-fuel ratio at, or close to, stoichiometric efficiency, but that would likely make a 961 run WAY to hot. It would have to be on the rich side to be cool, and safe.

But... I don’t know how much of this applies to the 961 cos I don’t know what the ECU does with the information. If it doesn’t do any of the ‘safety adjusting’ mentioned above then there’s really not much risk in doing what you say BT.

As y’all know, I run FCRs on my 920 and they’re fabulous things. But that only ever gets 99 octane fuel at the least and it’s tuned accordingly. I’d be rather nervous filling up in some isolated station, or supermarket, with their economy own brand ‘regular’.

I’ve got the FCRs for the 961 on the shelf already...
 
I’m not sure it’s quite that simple. For example, in modern high performance engines designed for high octane fuel, if you put low octane fuel in, you’ll lose a lot of power because the ECU does so on purpose to avoid detonation. At the least, it will alter ign timing and fueling. Some will limit revs, etc.

It’s the only way they can tune for max performance AND be safe.

Put carbs on an engine like that and you have to choose between being tuned for max performance OR safety. Can’t have both!

“Jetted properly” is another similar topic. “Properly” would normally mean an air-fuel ratio at, or close to, stoichiometric efficiency, but that would likely make a 961 run WAY to hot. It would have to be on the rich side to be cool, and safe.

But... I don’t know how much of this applies to the 961 cos I don’t know what the ECU does with the information. If it doesn’t do any of the ‘safety adjusting’ mentioned above then there’s really not much risk in doing what you say BT.

As y’all know, I run FCRs on my 920 and they’re fabulous things. But that only ever gets 99 octane fuel at the least and it’s tuned accordingly. I’d be rather nervous filling up in some isolated station, or supermarket, with their economy own brand ‘regular’.

I’ve got the FCRs for the 961 on the shelf already...

All valid concerns.
I would be jetting for performance of course.
AFM 13.4 to 13.8. Clean air, stoichiometric efficiency be damned.
Otherwise, no reason to add FCR's.

My Dyno guy tunes EFI, Carb-ed drag bikes.
I would get the carbs close to right, he can dial it in to whatever I want.
I'm not worried about fuel, I'm spoiled I guess.
Plenty of stations with high octane, but with ethanol contamination.

Naturally, the really difficult part is adapting a Triumph Bonneville Scrambler igniter box to the wiring harness to get the ignition to work after the ECU-ectomy.
 
Well , I wouldn't want to get rid of my EFI . It works pretty well and I like the fuel mileage I get. The only sensor I have actually had fail on my bike was the tip over sensor. We know how to troubleshoot this now and I have made an eliminator for troubleshooting it , which I posted a while back. My bike is running really well and I wish all 961 owners would have the same experience. The other sensors I replaced because I just wanted to make sure I had the best parts in there to hopefully avoid troubles. Is it ok to ask owners why they want to get rid of the EFI ? Is it the idle or what reason ??? There are solutions to most of this , as you guys have read about. We can make the SC Idle good man with NAIS ! And if you have the extra money to spend go for the new OMEX update . NOW , Why are the owners with the NEW 961's still having issues ? Not everyone of course , but it seems that Fast Eddie is the only trouble free machine ? I would hope that Norton could finally get the 961 sorted and reliable . Spend the the money Norton and get these bikes right for goodness sake .. !

Tony,

What is NAIS, a secret government organization?

I'm going to try a half measure this winter.
Send my ECU to SC Delta to get it unlocked.
Then have the bike Dyno tuned to replace lean map settings for cold starting/cold running issues.
The tuner has some experience with 961's.
He installed a PC for one owner because the ECU was locked and he couldn't access the map directly.
But he told me that he can fix my issues if I can get the ECU unlocked.
 
Do you have the intake manifolds too?

No. The ones Kenny used look like off the shelf one piece jobs to me, I was hoping to find something the same, but I don’t know if the head machining or stud pattern is different on the current heads. So it would be a case of measuring up and seeing what’s available. If not, they’ll need fabricating / turning up. Either way, it’s not gonna be the primary obstacle !
 
May I also mention the manifold pressure sensor. Rob sent me a replacement last year to fit as they had seen a few failures. Also the head temp sensor -
I had an uprated one fitted last service as the ones they had been using were on the limit of their working temperature spec.
 
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