poor idling

[guzzimeister]

Hi

 

I have a V11 2001 model with 54k miles showing. It runs very well except for a slight stumble and hunting at 3000 revs, which is the last sign of the famous V11 cough which I have adjusted out with a Power Commander. The bike runs great, up to 53mpg, but will not idle relaibly below 1200 rpm when it is hot. It hunts between 700 and 1200 rpm for a bit and then cuts out. It idles perfectly when cold. The PC has been adjusted to give 2% more mixture at 10% throttle and 2500rpm. I have checked the following:

- TPS, replaced in last 5000 miles and set up at 150mv on the idle stop

- throttle bodies balanced at 3000 rpm to within 2% pressure and the allowed 7% at idle

- iridium plugs are 3000 miles old

- regulator has recently been replaced and earthed out to the battery

- ECU and fuel pump relay connections and relays checked and relays changed

- body rubbers appear to be airtight

- air filter is a k&N clone in the standard airbox and was cleaned 3000 miles ago

 

I haven't checked the oil temp sensor, air sensor or fuel pressure regulator within the last 6000 miles, but I did at the last service with a dieagnostic kit. The problem has gradually developed over the last 3000 miles. I also seem to have to keep winding the idle stop further and further in to keep it idling.

 

Any ideas?

 

Cheers

 

Guzz

[raz]

Try a little more valve lash. Textbook says 0.10/0.15 mm. I'm running "the Raceco spec" 0.20/0.25 mm but you should see a lot improvement with just 0.15/0.20 too. I have tried this back and forth and I'm confident there was no other parameter involved: It mutes the "italian sneeze" at 3000 rpm completely AND it makes my idle rock stable.

 

I previously thought this had something to do with my heads being very worn but even after a full overhaul, it still holds true. Motoguzznix posted a technical explanation somewhere around here, it's not voodoo magic.

[docc]

G-meister, good advice from Raz on valve lash.

 

Also, to check: melted 30 amp regulator fuse, and nefarious advice on modifying the temperature sensor (helped me!)

 

Hey, go to your "profile" and show your location. It helps us all know better how to be of help.

[jimbemotumbo]

Good advice above. The only other thing I can tell you is to be absolutely certain that all linkages are disconnected from the TB when you set the TPS. I'm sure you've already considered that. I always did a careful valve adjustment to Euro specs then the TPS, then the TBs. I also balanced at just off idle, say 1500 rpm, rather than 3k rpm, as I feel it results in a better tune. If I varied from that approach I would see a bit of 3k hiccup.

 

YMMV

[Velf 2003]

Good advice above. The only other thing I can tell you is to be absolutely certain that all linkages are disconnected from the TB when you set the TPS. I'm sure you've already considered that. I always did a careful valve adjustment to Euro specs then the TPS, then the TBs. I also balanced at just off idle, say 1500 rpm, rather than 3k rpm, as I feel it results in a better tune. If I varied from that approach I would see a bit of 3k hiccup.

 

YMMV

 

In my case, changing the valve lash to greater values (I adopted the 20-25 option) centainly helped.

 

But the greatest improvement came from adjusting the temp sensor in the right cylinderhead. That did cure the Italian sneeze, made great improvement in not-running-hot-in-hot-wheater en improved heating up (meaning reaching optimumum oil temp quicker).

 

Maybey All (forummember) has already also adjusted his tempsensor in the way I`ve advised him, and he is willing to share the changes?

 

(All Roethisberger is his name, hopefully well spelled)

 

Good luck with all these advices!!

 

Velf2003

[guzzimeister]

Good advice above. The only other thing I can tell you is to be absolutely certain that all linkages are disconnected from the TB when you set the TPS. I'm sure you've already considered that. I always did a careful valve adjustment to Euro specs then the TPS, then the TBs. I also balanced at just off idle, say 1500 rpm, rather than 3k rpm, as I feel it results in a better tune. If I varied from that approach I would see a bit of 3k hiccup.

 

YMMV

 

In my case, changing the valve lash to greater values (I adopted the 20-25 option) centainly helped.

 

But the greatest improvement came from adjusting the temp sensor in the right cylinderhead. That did cure the Italian sneeze, made great improvement in not-running-hot-in-hot-wheater en improved heating up (meaning reaching optimumum oil temp quicker).

 

Maybey All (forummember) has already also adjusted his tempsensor in the way I`ve advised him, and he is willing to share the changes?

 

(All Roethisberger is his name, hopefully well spelled)

 

Good luck with all these advices!!

 

Velf2003

Thanks fellas, I'll look at the temp sensor and let you know how I got on

 

Cheers

 

Guzz

[Skeeve]

 

(All Roethisberger is his name, hopefully well spelled)

 

 

I'm fairly certain there's supposed to be an "L" in there somewhere...

[Paul Minnaert]

well look at the intake rubbers

[vuzzi]

Hi

 

I have a V11 2001 model with 54k miles showing. It runs very well except for a slight stumble and hunting at 3000 revs, which is the last sign of the famous V11 cough which I have adjusted out with a Power Commander. The bike runs great, up to 53mpg, but will not idle relaibly below 1200 rpm when it is hot. It hunts between 700 and 1200 rpm for a bit and then cuts out. It idles perfectly when cold. The PC has been adjusted to give 2% more mixture at 10% throttle and 2500rpm.

 

i 'm not sure 2% more mixture will help. Setting the tps at 150 mV w clossed throttle will not work for every bike. The dealer offset mine at 520 mV when idling at 1100 rpm.

 

maybe this link will help?

 

http://www.v11lemans.com/forums/index.php?showtopic=16351&st=0&p=175748&hl=position&fromsearch=1entry175748

[motoguzznix]

Hi

 

It idles perfectly when cold.

- TPS, replaced in last 5000 miles and set up at 150mv on the idle stop

- throttle bodies balanced at 3000 rpm to within 2% pressure and the allowed 7% at idle

HI Guzz

 

The TPS has to be adjusteed at 150 mV when the throttle is closed completely, not on idle stop. This has to be done with the linkage disconnected. Close the bypass screws. Then open the throttle to 510 - 525 mV. Connect the linkage, start the engine and synch the throttles. Now your idle speed should be around 1000 rpm. When too low open both bypass screws to the same amount, 1/2 a turn or 1 turn (revolution).

 

I would recommend to perform this with the PC disconnected.

Next step needs a CO meter and hardware/software to adjust the CO in the exhaust gas to 3,5 %. If idle changes, readjust id at that stage.

 

Hope you get it.

[guzzimeister]

well look at the intake rubbers

 

Thank you Paul, it was a hole about 20mm long in the LH intake rubber. Always start with the simple stuff first.....

 

At the risk of starting a very long thread, I have replaced a few of these, and find the ratio of left to right rubbers to be about 3 to 1. Anybody got the same experience?

 

Cheers and thanks to all for your help

 

Guzz