Spark Plugs
- Thread starter Baza 07
- Start date
ed gets a virtual thick ear 
All looking very black and coked... Mine never look like that, they're always a beige/light grey ish colour (bottom plug is always a tad oily, but the electrodes are as above...)
Might be a clue, but if you've been unable to have it run properly for a bit, then I guess that could also explain it?
Sent from my SM-S908B using Tapatalk
Might be a clue, but if you've been unable to have it run properly for a bit, then I guess that could also explain it?
Sent from my SM-S908B using Tapatalk
Obviously running rich.
Ok I’ve now established it’s running Rich, are there any simple fixes I could do 
Cheers Baza
Cheers Baza
Smiffypr
Registered user
I can't tell anything from those because I can't see the central electrodes in your side views, and only the central electrode gets up to spark plug operating temperature.
When you do look at the central electrodes, the colour will only tell you how it was running immediately before the engine was stopped, so if it had been idling for a few seconds they would reflect the idle mixture.
When you do look at the central electrodes, the colour will only tell you how it was running immediately before the engine was stopped, so if it had been idling for a few seconds they would reflect the idle mixture.
Hi mate,are these better,a quick run down on my riding, max 10 miles every now and then, round town mostly
PS would a new set of plugs be in order
Attachments
Smiffypr
Registered user
When I said "central electrode" before, I should have said "central electrode insulator", but you obviously got what I mean as your pictures show the insulator clearly and the colours look fine.
Sounds good to me, what’s the sooty stuff around the plug, also I take it, it doesn’t need new plugs
BTW Thanks very much for your replies
Cheers Baza
Smiffypr
Registered user
My opinion would be that it doesn't desperately need new plugs, but I can see wear on the electrodes, i.e. the centre electrode has a slight taper looking from the side and a slight ovality looking from the end. If they were mine I would measure the actual gaps then decide.Sounds good to me, what’s the sooty stuff around the plug, also I take it, it doesn’t need new plugs
BTW Thanks very much for your replies
Cheers Baza
The soot is soot. I would say that is normal from when the engine has been idling before being turned off. My guess is that will burn off once the engine it thoroughly hot or under load. (Bear in mind that the mixture needs to be richer at idle than when it is under load, even when the engine is hot). One way to see if there is going to be a build up of "coke" over time is to look at the plugs straight away after the engine has been running under load and fully up to temperature. Ideally you would get it up to temperature, then at a safe and convenient place turn it off with the kill switch. Do not close the throttle first, switch it off while the engine is still driving. Pull the clutch in and coast to a stop, ideally outside your house. Then whip the plugs out (doesn't matter if the engine has cooled down, as long as it isn't run again. The plugs then will reflect how they are when running. (We used to call this a "plug chop" and we would do it at full speed to check main jet sizing with carbs.)
As you seem to be the “Plug Man” what plugs would you recommend for my bike it’s a 2010 BMW R 1200 GS
Thanks again for all your advice
Cheers Baza
Smiffypr
Registered user
I'm no plug expert, but spent may hours "tuning" carburated engines. For an unmodified bike I would stick with the maker's recommendations, and I would stick to plugs from the same region, i.e. use Japanese plugs in Japanese engines and German plugs in German engines, the heat ratings aren't always an exact match between continents even when they are listed as direct equivalents.As you seem to be the “Plug Man” what plugs would you recommend for my bike it’s a 2010 BMW R 1200 GS
Thanks again for all your advice
Cheers Baza
You can change from standard to exotic materials for longer life at greater cost, but these only seem worth it when the standard plugs don't last long (this was the case with my "tuned" 1980 R100RS).
As far as I can find there is only one plug available for the 2010 GS Twin Cam, that is the factory recommended NGK plug.As you seem to be the “Plug Man” what plugs would you recommend for my bike it’s a 2010 BMW R 1200 GS
Thanks again for all your advice
Cheers Baza
In the TC plugs only seem to last 12K Miles before going out of tolerance
I tried machining the last 2 threads from the nearest equivalent Denso iridium plugs on 2 sets and they only lasted 18K miles so not worth the effort.
On pre TC bikes 40K miles on iridium plugs was not a problem.
Thanks mate
Smiffypr
Registered user
Interesting, that suggests that BMW couldn't find a German made plug that worked. If I were you I would stick with the recommended ones and just change them at the required interval. If you really want to experiment, you could go one step cooler (That means the centre electrode runs cooler in the same situation by virtue of it conducting heat away to the head faster) and that might make them last longer but you might find that the plugs then foul up at low speeds. If you experiment, you do need to carry the standard plugs with you and the tools you need to change them, and if you want to go down that route you should be riding a 1960s bike!
No experimenting here bro, a new set going in tomorrow and that’s it
BTW my first bike at 15/16 was an Ariel Arrow
Going through a slight protracted service of my GSA. Today valves checked and new plugs fitted.
A bit like the comments above, my central electrodes were all worn - being replaced regardless - the wear was clear and pretty much identical on each plug. They've done about 20-25k miles. The TC seems to get through plugs
. But I have to also say, without checking them, I wouldn't notice! The motor runs really well.
Some pics below. May be of interest.
Hopefully it's clear which are the upper and lower plugs!
Sent from my SM-S908B using Tapatalk
A bit like the comments above, my central electrodes were all worn - being replaced regardless - the wear was clear and pretty much identical on each plug. They've done about 20-25k miles. The TC seems to get through plugs
. But I have to also say, without checking them, I wouldn't notice! The motor runs really well.Some pics below. May be of interest.
Hopefully it's clear which are the upper and lower plugs!
Sent from my SM-S908B using Tapatalk
Cheers Slippery,interesting post when my new ones turn up I’ll take the same photo, at least yours have the brownish tinge to them, mine are really sooty, but apart from the backfire mine to runs very well, I’ve no idea how long the plugs have been in mine, the bike has done 52k and is a 2010 plate.
Cheers Baza
Cheers Baza
Similar threads
