Hunting and High idle permanent fix! - TRIAL

Last few rides this week the hunting consistently comes in after about 8mls ( first stop at lights) All I then do is turn off the ignition count to 10 then start up again with the tick over returning to 1200. This strongly suggests to me the hunting is not caused by leaks but ECU/sensors not managing things properly. BTW if I ever so slightly add a bit of throttle I can keep revs constant at say 1800 whilst in neutral.
 
Graeme Mitchell said:
Last few rides this week the hunting consistently comes in after about 8mls ( first stop at lights) All I then do is turn off the ignition count to 10 then start up again with the tick over returning to 1200. This strongly suggests to me the hunting is not caused by leaks but ECU/sensors not managing things properly. BTW if I ever so slightly add a bit of throttle I can keep revs constant at say 1800 whilst in neutral.
Click to expand...
If you have covered leaks,cleaning out the intake port, filters clean then the issue might be power going the idle air control valve. We found that at idle the charging system along with the SCS ECU was not providing enough to full/smoothly operate the IACV. The easy test is to have a full charged and full CCA battery on a cold bike. (We found the a lithium held better voltage at startup as well.) Leave headlamp off, turn key, switch to run, let fuel pump cycle and then start. Idle should raise then should mellow as the valve does its thing. Look at voltage during start up. How much does it drop?

Check wires at ecu, Dielectric grease is your friend, and check the pins for the IACV to make sure they are full seated as we have found loose/ poor connections.

If you think the valve is suspect you can pull the valve and cycle to see the solenoid raise and lower the valve.

The IACV valve is the last thing to worry about and electrically checking it is super easy to confirm operation.

Unlocking the ECU is helpful in locating these issues as well.
 
City Garage said:
If you have covered leaks,cleaning out the intake port, filters clean then the issue might be power going the idle air control valve. We found that at idle the charging system along with the SCS ECU was not providing enough to full/smoothly operate the IACV. The easy test is to have a full charged and full CCA battery on a cold bike. (We found the a lithium held better voltage at startup as well.) Leave headlamp off, turn key, switch to run, let fuel pump cycle and then start. Idle should raise then should mellow as the valve does its thing. Look at voltage during start up. How much does it drop?

Check wires at ecu, Dielectric grease is your friend, and check the pins for the IACV to make sure they are full seated as we have found loose/ poor connections.

If you think the valve is suspect you can pull the valve and cycle to see the solenoid raise and lower the valve.

The IACV valve is the last thing to worry about and electrically checking it is super easy to confirm operation.

Unlocking the ECU is helpful in locating these issues as well.
Click to expand...
Hi
Gone through suggestions but nothing obvious. When I first start with a fully charged battery and cold engine the revs are holding constant about 1500revs. Not sure what to look for in voltage drop as the reading says 12.7 volts before turning ignition then increases to plus 13 volts when running
 
Have you cleaned out the IAM and Cap ? Might be some debris or other gunk in there restricting its closing . So when you start the bike , do the revs climb up to 1800-2000 or so then settle back to 1500 rpm ? When you go for a ride are you still getting the hunting revs , or is this now gone and you get a constant high idle 1500 rpm ? This has to be solveable because there are too many OMEX Euro 3 that work . Have you considered trying this :

https://www.accessnorton.com/proxy.php?image=https%3A%2F%2Fi.vgy.me%2FmKN6AG.jpg&hash=574b928ca078b1b1be4854e12353c3c5
 
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TonyA said:
Have you cleaned out the IAM and Cap ? Might be some debris or other gunk in there restricting its closing . So when you start the bike , do the revs climb up to 1800-2000 or so then settle back to 1500 rpm ? When you go for a ride are you still getting the hunting revs , or is this now gone and you get a constant high idle 1500 rpm ? This has to be solveable because there are too many OMEX Euro 3 that work . Have you considered trying this :

https://www.accessnorton.com/proxy.php?image=https%3A%2F%2Fi.vgy.me%2FmKN6AG.jpg&hash=574b928ca078b1b1be4854e12353c3c5
Click to expand...
No, but will give them a clean.

Revs are only 1500 constant when starting from cold. Starting from warm they generally hold at 1200-1300 for a while until the hunting starts between say 1400 and 1800 which is most noticeable when stopped and in neutral. It sounds like I am deliberately giving it a bit of throttle so get some looks every now and then - not that bothers me!
 
Graeme Mitchell said:
No, but will give them a clean.

Revs are only 1500 constant when starting from cold. Starting from warm they generally hold at 1200-1300 for a while until the hunting starts between say 1400 and 1800 which is most noticeable when stopped and in neutral. It sounds like I am deliberately giving it a bit of throttle so get some looks every now and then - not that bothers me!
Click to expand...
I can just add that I have had hunting idle for as long as I have owned the bike since 2015. I have changed all the sensors and still I had hunting. I replaced the IACM motor as per SCS instructions on setting idle the motor was defective. After all was said and done, I still had hunting, I had put a clamp on the silicone hose from the IACM as there was none. I was all but ready to go the DELTA400 route when I thought I would check the hose from the IACM to the manifold intake and it was not just leaking but it was off. Installed a clamp on the silicone hose at the manifold and I know after 6 years have an Idle. I went for a ride, little cold however I stopped and started many times and always an idle (1100 to 1150). So for my two cents the idle problem has to do with the IACM motor or a leak in the line to the manifold. I have also put a mini filter on the hose to the IACM and plugged the air box so the IACM is receiving only good air. I also plugged the other tube to the air box as my hose from the rocker cover runs down to an air oil separator behind my left foot peg. Now with my idle and my PC5 DYNO map the bike runs like I always felt it should.
 
I've been reading trough all of this..interested to see how I'll get on. Ian Wilson has posted some interesting vidos on you tube and noticed this last night:



Really interesting stuff on crank case venting in another video!

Ian, can you give any detail on the new and improved cold start?
 
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