Hunting and High idle permanent fix! - TRIAL

The manual seems to show a gasket with O rings between the throttle body and gasket, and between the head and gasket.
I checked my 2013 961, and I can't see any gasket.
Certainly nothing 1/16 of an inch thick. That would be very apparent.
Hmmmm.

Hunting and High idle permanent  fix! - TRIAL
Hosted on Fotki
 
The gasket is 1/16 inch hard poly with embedded rubber O rings. Quite nice, actually. I thought that was rather thick and not is not crushable. Curious, Richard, having earlier imports of '13 and '14, did you or your dad's bike come with that?

My dads red SF has this gasket. The first 10 bikes in Canada have this gasket. The rest don’t. My dads SF is the 5th bike in canada and first red bike in Canada. My dads 2013 SE was the 30-somthing-th bike in canada. So must have been a change during that time. Also, when we asked about it in 2014 Simon said it was unnecessary so we left it at that.
 
Last edited:
We've been reluctant to share this and again - TRIAL USE ONLY!!!

Since February 2018 my dad was sick of the hunting idle. He was determined to solve it. And he did. But here's the back story:

Seems like the newer ECU's have more power to better control the IDLE AIR MOTOR but not everyone wants to spend money on a new ECU. And on top of that, there are still a few bikes with the new ECU's that have that annoying hunting idle and high idle situation. And there are some IDLE AIR MOTORS that are faulty. And there are VALVE BODIES that are adjusted incorrect or poorly made with the butterfly flaps not tuned. ????? Meaning one flap when closed has a .003" larger gap then it's neighbor. All around sucks! and makes for an unhappy owner. If a custom "hand made" builder were to assemble this bike, every detail would be looked over and tuned. So that's what we are doing.

So even after you tune the flaps, clean the IAM, change all the sensors, re-map the bike. With the pre-2016 bikes there still seems to be this issue. So my dad warmed up his bike to full running temp. put a ball bearing in the hose between the IAM and the air box. Then, cranked up the idle screw so it actually does control the idle. BAM!!!! Perfection. Like a new bike.

I did this to mine about 3 weeks ago. BAM!!! a new bike. Why did I wait so long to try this??? The idle will always drop smoothly to where you told it to and NEVER EVER CLIMBS or hunts!!!! Say you're doing 120km/h at 4,800 rpm and pull in the clutch. ....BAM!!! PERFECTION!!!!

This comes with a small sacrifice though. Cold starting is non existent. You have to hold the throttle when starting for about one minute.

Is it worth it?? Definitely!!!

Do I miss perfect cold starts? Definitely!!!

Would I ever take out the ball bearing and go back to the way it was??? NEVER!!!!


GOOD LUCK OWNERS!!! Try if you dare. And again. Trial only.

*******Only do this if your bike is out of warranty and you feel 100% comfortable doing so.*****

Just clarifying... this ball bearing you put in the hose between the IAM and the air box, I'm assuming, is large enough to block air altogether or am I totally misunderstanding. I would like to try this before going down the route of ECU upgrade
 
Just clarifying... this ball bearing you put in the hose between the IAM and the air box, I'm assuming, is large enough to block air altogether or am I totally misunderstanding. I would like to try this before going down the route of ECU upgrade


You got it. Basically anything to block the air.
 
this is unreal. i also see that rob has not addressed this on line but has answered some other things you posted. IMHO the factory should be happy that you guys are keeping the flag flying in canada after all you have put up with from them.

Normally we would report this to the factory first to confirm and let them put out a letter to dealers to correct but the factory have officially told us to get lost and never contact them so I will now have to rely on the public to discover and confirm these issues. Looking forward to your help.
 
Just clarifying... this ball bearing you put in the hose between the IAM and the air box, I'm assuming, is large enough to block air altogether or am I totally misunderstanding. I would like to try this before going down the route of ECU upgrade

Because its crappy weather im not able to test it if the washers under the bolt heads will work. If they do work and the entire time it was a vacuum leak then I will be removing the ball. We do smoke tests on engines and have found loose bolts and a leak at this flange but high idle being so inconsistent, we never found a leak in my bike here. Could be so slight and we missed it because its only when the bike is super hot. Try placing washers under the heads of your bolts first. If that doesn’t do anything then try the ball. The ball for sure works for me but as was brought up, i have o2 eliminated so that may keep me safe. Rob said you’ll blow the engine so please only give it a try to prove the IAM is the cause.

Im convinced the IAM is the real issue here. Maybe the wrong one not designed for heat. Or maybe in thr wrong spot. Too close to heat. Or maybe the ECU is not providing it enough power hence why the ECU upgrade is recommended because it may provide more power to this IAM to move it when it starts binding from heat. When we brought this issue up to Simon years ago, he told us its our fuel thats the problem and we need to clean the IAM more often. hence why I have a manual on it. But it really didn’t make a difference. And canada has great ethanol free fuel.

So ?????? Not sure what to say. But temporarily blocking will prove if your bike can run amazing. Please convince yourself you should try it and don’t listen to me on this one. Im only sharing what I did and you’re welcome to try it too.
 
Im convinced the IAM is the real issue here. Maybe the wrong one not designed for heat. Or maybe in thr wrong spot. Too close to heat. Or maybe the ECU is not providing it enough power hence why the ECU upgrade is recommended because it may provide more power to this IAM to move it when it starts binding from heat.

My previous 2012 bike with SC ECU suffered from high idle - anything up to 2800rpm - the factory changed the IAM but no difference - I wrapped the IAM in exhaust bandage to protect it from the heat & that solved it
 
Im convinced the IAM is the real issue here. Maybe the wrong one not designed for heat. Or maybe in thr wrong spot. Too close to heat. Or maybe the ECU is not providing it enough power hence why the ECU upgrade is recommended because it may provide more power to this IAM to move it when it starts binding from heat.

My previous 2012 bike with SC ECU suffered from high idle - anything up to 2800rpm - the factory changed the IAM but no difference - I wrapped the IAM in exhaust bandage to protect it from the heat & that solved it


Thats great info!!!!
Thanks for sharing!!!!!

So perhaps it was a mistake that the heat insulation plate was removed and is the real reason its back. Im assuming the heat plate was Dreers idea. Because if Simon designed it he wouldn’t have removed it. If thats the fix then I hope Norton mails every owner one of these plates as a recall. I wish the weather was better here to test this out. My dads red SF that has this plate never once had high idle. So this is really interesting now.

So it could be the screws
It could be the lack of the plate
Could be both related to each other
Could be heat on IAM
 
It is probably a good idea to have the insulator plate on just to reduce some of the heat to the throttle body in general.
 
If the throttle body was separated from the cylinder head sufficiently, as to prevent heat transfer, this would surely be the perfect solution...

For example... by a small supercharger unit...
 
Last edited:
Goes to show how sensitive the IAM is though. I don't have the plate, mine was ever so slightly cocked that you really couldn't even see it, yet two turns of one screw cure it. Don't forget, last year my bike bounced....hard. That may have just thrown it off a bit. That little POS is connected to quite a heavy piece of equipment, attached to a too heave hose to the airbox. AND...its the second time it shook loose.
 
Hunting and High idle permanent  fix! - TRIAL

Next Project : Install 1/16 in. thick Heat insulator with built in O-rings . As you see from the drawing this goes between cylinder head and throttle body .
 
I have idle issues also. But mostly I am doing this because it is a good idea to isolate the throttle body from excessive heat.
 
Last edited:
Back
Top