Idle problem solved

cliffa said:
As far as I'm aware I think you have point 2 slightly wrong. You need to plug (not cap) the passageway where the IAC normally connects to the throttle bodies, so there is no path between them otherwise the mixture robbing will continue. See earlier in the thread the red bung which iwilson used.
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yes sorry, my poor english, I understood the matter is to avoid any passage of mixture between the two cylinders.
But other points?
 
Portofino Norton's Garage said:
yes sorry, my poor english, I understood the matter is to avoid any passage of mixture between the two cylinders.
But other points?
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1) remove the whole IAC body with relevant tubes? = YES ( you don't have to remove the Idle Motor and cap buy why keep it ?)
2) plug the fit for IAC admitting tube on the airbox? =YES (plug the air box and throttle body inlet)
3) disconnect the electrical plug to IAC valve and leave it somewhere in the bike detached? No claims from the ECU? = YES (disconnect battery before plugging or unplugging the Idle Motor)

sorry for asking these details but I would take advantage of your skills, avoiding boring experiments . Thanks a lot in advance for your patience.
 
thank you Tony. Sorry to put again questions but I remember that in another thread Richard Coote explained he got same results only putting an iron ball into the rubber duct going from the valve to the throttle body; that is something similar but not the same iwilson intervention, since it simply doesn't allow air to the throttle body but mixture exchange between the two cylinders remains possible inside the throttle body itself.
So how would you comment these different level of change? Of course that Richard one is by far more simple to operate.
 
Are you using the O2 sensors in the exhaust pipes ? If so , you would be better served blocking the passage between the throttle bodies. This is only an issue when the throttle valves are closed during idle . The Richard-7 ball bearing block does work and you can get the throttle stop position set first this way quick and easy .
 
I noticed that on the first start up of the day when I ride after the bikes sat for weeks / months, the idle is high (1800-2000 rpm) then it starts to surge.
I’ll let it get to operating temps, blip the throttle and if that doesn’t idle it down, I’ll shut it off then restart then all is smooth and steady.
 
Voodooo said:
I noticed that on the first start up of the day when I ride after the bikes sat for weeks / months, the idle is high (1800-2000 rpm) then it starts to surge.
I’ll let it get to operating temps, blip the throttle and if that doesn’t idle it down, I’ll shut it off then restart then all is smooth and steady.
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Your bikes are MK2 Euro 3 OMEX correct ? 2016/2017 Both bikes doing it ? Commando and Domi ?
 
TonyA said:
Your bikes are MK2 Euro 3 OMEX correct ? 2016/2017 Both bikes doing it ? Commando and Domi ?
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I rode the commando 2 times so far this year since winter. I’ve only had it happen on the commando. Both my commando and dominator are both 2016 and OMEX.
 
Voodooo said:
I rode the commando 2 times so far this year since winter. I’ve only had it happen on the commando. Both my commando and dominator are both 2016 and OMEX.
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Hello Scott , Yes and I remember your Domi has the O2 sensors removed with the megas . Would you be willing to try the O2 sensor delete plugs on the Commando ?
 
TonyA said:
Hello Scott , Yes and I remember your Domi has the O2 sensors removed with the megas . Would you be willing to try the O2 sensor delete plugs on the Commando ?
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Who has those? Are you talking about the o2 plus that eliminates the o2 sensors or ones that keep the o2 in place but raise the o2 from the exhaust header pipe? If I remove the o2 completely what’s going to keep the check engine light off?
 
Voodooo said:
Who has those? Are you talking about the o2 plus that eliminates the o2 sensors or ones that keep the o2 in place but raise the o2 from the exhaust header pipe? If I remove the o2 completely what’s going to keep the check engine light off?
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The resistor plugs that plug in to where your O2 sensors now plug in the harness . You can leave the sensors in the pipes if you want to . Norton uses the Aprilia style plug on the harness. You can find them on ebay . We know the resistor values and you can make your own if needed.

Look for these on ebay :

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Norton Commando 961 O2 Oxygen Sensor Eliminator Plugs (2 plugs)​


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TonyA said:
The resistor plugs that plug in to where your O2 sensors now plug in the harness . You can leave the sensors in the pipes if you want to . Norton uses the Aprilia style plug on the harness. You can find them on ebay . We know the resistor values and you can make your own if needed.

Look for these on ebay :

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mcconnectors (38 )
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Norton Commando 961 O2 Oxygen Sensor Eliminator Plugs (2 plugs)​


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Will the bike run rich / lean?
 
Tony I removed by far the O2 sensors and plugged the wires as was suggested with the resistors. But I still not understand if I have to move to iwilson or Richard Coote modification.
 
Portofino Norton's Garage said:
Tony I removed by far the O2 sensors and plugged the wires as was suggested with the resistors. But I still not understand if I have to move to iwilson or Richard Coote modification.
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You don't have to go any further. How is the bike running so far ? This is what I am running on my bike now and it works good. Try this for a while and see how your bike runs. Why don't you recap for us what is on your bike : Exhaust system type , Which ECU , which map , which air filter , what year is your bike etc ..
 
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Tony I've been following this fully interesting forum by years so my Commando 961 SE 2013 is well update with all the changes stated by Richard Coote (coils, spark plugs and wires, Bosch sensors and injectors etc). Everythings were done by years so far. The bike runs better, much better that Norton made it, but still have the well known issues at idling (not always, only when it wants :confused: of course) and low/zero throttle operations.You never know how the engine will behave approaching a curve, sometimes very smooth as it should work, sometimes rough and with boring hiccups and on-off.
This is why I would try the iwilson experience, but at the same time , I would understand the difference from the simple closing the hose coming from the IAC valve to the throttle body that Richard suggested years ago
 
Today I tried a first attempt in the path of IAC removing. I want to proceed step by step to understand the different effects modifications cause.
So in order to easily simulate the Richard Coote mod (a ball obstructing the hose from the IAC to the Throttle body), without disassamble nothing I simply disconnected the hose from the airbox spigot to the IAC valve (the one where IAC valve breathes). I started at idle the bike and after a few seconds I plugged the hose with my thumb. Immediately the bike stalls. So I thought I will have had to adjust the screw for zero butterfly valves position in the throttle body. Again to avoid any useless intervention I just simulate this taking a bit of throttle open with the throttle grip. Nevertheless the bike immediately stalls when I plug the hose and dont' permit air flowing onto the throttle body. So I indeed don't understand how either closing the hose from the valve to the throttle body (Richard Coote solution) or even more the passage in the body between one cylinder and the other (iwilson solution) the bike can still idle. I don't consider any difference MKI ( mine) or MKII (as iwilson Dominator is) can have an influence on this. What am I doing/thinking wrong?
 
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Portofino Norton's Garage said:
Today I tried a first attempt in the path of IAC removing. I want to proceed step by step to understand the different effects modifications cause.
So in order to easily simulate the Richard Coote mod (a ball obstructing the hose from the IAC to the Throttle body), without disassamble nothing I simply disconnected the hose from the airbox spigot to the IAC valve (the one where IAC valve breathes). I started at idle the bike and after a few seconds I plugged the hose with my thumb. Immediately the bike stalls. So I thought I will have had to adjust the screw for zero butterfly valves position in the throttle body. Again to avoid any useless intervention I just simulate this taking a bit of throttle open with the throttle grip. Nevertheless the bike immediately stalls when I plug the hose and dont' permit air flowing onto the throttle body. So I indeed don't understand how either closing the hose from the valve to the throttle body (Richard Coote solution) or even more the passage in the body between one cylinder and the other (iwilson solution) the bike can still idle. I don't consider any difference MKI ( mine) or MKII (as iwilson Dominator is) can have an influence on this. What am I doing/thinking wrong?
Click to expand...
Are you opening the throttle valves enough ? Try and bring the revs higher say to 2000 or 2200. To must hold it there open with a throttle stop of some sort then try plugging. Conversely, loosen the lock nut on the throttle stop and screw in the idle screw until you raise the revs about to 2200 , then try to block the IAC.
 
As Tony said you need to adjust the idle screw to crack the butterflies open far enough to allow the engine sufficient air with the IAC blocked. The difference between my solution and Richards is simple. He blocks the tube but not the passage between the two throttle bodies. My solution not only blocks the IAC but also prevents one cylinder stealing fuel from the other which gives a much smoother and consistent idle.

This is the result a perfect start from cold! It’s been a few years now and nothing has changed, perfect start hot or cold. No plug fowling.

 
iwilson said:
As Tony said you need to adjust the idle screw to crack the butterflies open far enough to allow the engine sufficient air with the IAC blocked. The difference between my solution and Richards is simple. He blocks the tube but not the passage between the two throttle bodies. My solution not only blocks the IAC but also prevents one cylinder stealing fuel from the other which gives a much smoother and consistent idle.

This is the result a perfect start from cold! It’s been a few years now and nothing has changed, perfect start hot or cold. No plug fowling.

Click to expand...

So you’re saying you removed the IAC completely and left it off and plugged the port? Then adjusted the idle to smoothen it out at around 500-600 rpm?
no other changes?
 
iwilson said:
Come on up and I'll stick a probe up your back end! :eek: But seriously I'm in Pukekohe, feel free to bring your bike up. What exhaust system are you running? Needs to be CAT free and not have a crossover pipe to measure the lambda values.
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So I have a Domi with megaphone and a commando with a decat x pipe. Are you saying this can only be done with the megaphones?
 
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