Board logo

Lumpy Idle
Major Stare - 3/6/11 at 07:11 PM

Had a lumpy idle on the R1 which has gotten worse since having the engine, especially noticable since the Power Commander and rolling road was completed 2 weeks ago.

Had a look at the map today and just cant get a smooth tickover.

Took a plug out and a quick call to Andy @ AB with plug part numbers - the engine has NGK Iridium plugs, that should'nt be in the engine as they are race plugs and need regular changing. They have been in the engine since buying it - so 2.5yrs old and could account for the deteriorating tickover.

Thanks to Andy who's sorting a "proper" set of plugs.
Gutted another weekend not using the car

eddie99 - 3/6/11 at 07:15 PM

We had some of those NGK Iridium plugs go on us at Snetterton on a test day, they seem to be quite troublesome, Glad you got it sorted though!

adithorp - 3/6/11 at 07:27 PM

I've just renewed a set of NGK Iridium plugs after 10000miles trouble free use.

britishtrident - 3/6/11 at 07:34 PM

NGK Iridium should be good for the life of the engine even without re-gapping.

Sounds like the plugs were the wrong heat range for the engine or mixture is out.

Major Stare - 3/6/11 at 07:36 PM

quote:
Originally posted by britishtrident
NGK Iridium should be good for the life of the engine even without re-gapping.
Sounds like the plugs were the wrong heat range for the engine or mixture is out.


Nope, Andy checked..... they are definetly the wrong plugs

britishtrident - 3/6/11 at 07:56 PM

quote:
Originally posted by Major Stare
quote:
Originally posted by britishtrident
NGK Iridium should be good for the life of the engine even without re-gapping.
Sounds like the plugs were the wrong heat range for the engine or mixture is out.


Nope, Andy checked..... they are definetly the wrong plugs




Thats what i said Wrong heat range = Wrong choice of plug number.

Iridium is the centre electrode tip material which is nothing to do with heat range of the plug.

You have to use plugs of the correct heat range number to match the engine and the conditions of use, if you are using too soft (hot) a plug the plug will overheat causing the insulation ceramic nose of the plug to breakdown causing a misfire , using too hard (cold) a plug will result in oil fouling of the plug.

A weak mixture will cause plug to run hotter demanding a harder (colder) plug.
A rich mixture will tend to require a softer (hotter) plug.

Racing plugs tend to be "hard" sometimes called "cold so they don't breakdown under extreme conditions, while plugs for normal/town/shopping use are softer (hotter) to avoid cold fouling. In the old days racing engines were started on soft plugs and switched to hard plugs before the car/bike went to the grid.

britishtrident - 3/6/11 at 08:19 PM

This explains it NGK technical info

Major Stare - 7/6/11 at 07:09 AM

New plugs ordered from Andy & will be fitted this week.

If the lumpy/inconsistant idle doesnt sort itself out, im getting rid