Spark Plug Replacement every 8,000mi

[redbirds_imp]

Is there an Iridium plug option? I changed over to Iridium plugs on my Triumph first time they were due for inspection.

Not from NGK. Their website lists no other compatible options to the standard LMAR8A-9S.

http://ngk-sparkplugs.com/lmar8a9s-p-2844.html

Not from NGK. Their website lists no other compatible options to the standard LMAR8A-9S.

http://ngk-sparkplugs.com/lmar8a9s-p-2844.html
Thanks for the info.

I hope the standard plugs will last at least 20K miles with regular inspection and cleaning. Last car I had with standard plugs was a Jeep Liberty and I was able to get 40K from them before I switched to Platinum plugs.

[the Ferret]

Just my opinion

Honda calls for ridiculous early replacement on motorcycle plugs. Same type plugs (std NGK) in my ST were replaced at 25,000 miles (called for at 16,000) and looked new. Some on the ST forum have put over 50,000 miles on them. Same type plugs in my Honda Civic call for replacement at 110,000 miles.

These are fuel injected, and computer controlled. On a non modified bike they can't run lean, rich, or misfire. Every firing should be text book as the engineers designed it.

And while I'm harping, why of earth should a standard NGK plug cost $20 apiece?

I might replace mine at 25,000 miles if I feel it needs it. For some of us replacing every 8,000 miles could be twice a year.

Disclaimer: I am not an engineer .... YMMV

[sanoke_imp]

Just my opinion

Honda calls for ridiculous early replacement on motorcycle plugs. Same type plugs (std NGK) in my ST were replaced at 25,000 miles (called for at 16,000) and looked new. Some on the ST forum have put over 50,000 miles on them. Same type plugs in my Honda Civic call for replacement at 110,000 miles.

These are fuel injected, and computer controlled. On a non modified bike they can't run lean, rich, or misfire. Every firing should be text book as the engineers designed it.

And while I'm harping, why of earth should a standard NGK plug cost $20 apiece?

I might replace mine at 25,000 miles if I feel it needs it. For some of us replacing every 8,000 miles could be twice a year.

Disclaimer: I am not an engineer .... YMMV

I agree with your assessment. I think there is a bit of a revenue stream involved with some of the recommended maintanence. One of my other bikes is a 2008 Suzuki V-Strom. It's recommended to have the valves checked and the throttles synced every 8,000 miles. I've periodically checked the valves and in over 98,000 miles I've never had to adjust one yet. I've also ignored the throttle sync with no issues. I figure if I don't mess with the linkage, then they shouldn't get out of adjustment.

What it really boils down to is you just need to use a little common sense and do what needs to be done when you think it needs it.

[Haystack_imp]

My Valkyrie went 103,000 miles before I sold it with original plugs...always ran great. I expect the same from the CB1100.

I read somewhere that U.S. regulations require ignition systems on autos to run 100,000 miles before expected replacement: any truth to this? With motorcycles?

[flynrider]

My Valkyrie went 103,000 miles before I sold it with original plugs...always ran great. I expect the same from the CB1100.

I read somewhere that U.S. regulations require ignition systems on autos to run 100,000 miles before expected replacement: any truth to this? With motorcycles?

i don't think there is any regulation mandating 100K mile plugs. Most auto manufacturers tend to use them because they can cram more stuff into the engine compartment without worrying too much about the plugs being easily accessible. Since they only have to come out every 100K miles it's not as much of a big deal if the procedure is a bit more difficult.

Motorcycles definitely don't have that requirement. The standard NGK plugs on our CB1100s are evidence of that.

[Dakota_imp]

My Valkyrie went 103,000 miles before I sold it with original plugs...always ran great. I expect the same from the CB1100.

I read somewhere that U.S. regulations require ignition systems on autos to run 100,000 miles before expected replacement: any truth to this? With motorcycles?

i don't think there is any regulation mandating 100K mile plugs. Most auto manufacturers tend to use them because they can cram more stuff into the engine compartment without worrying too much about the plugs being easily accessible. Since they only have to come out every 100K miles it's not as much of a big deal if the procedure is a bit more difficult.

Motorcycles definitely don't have that requirement. The standard NGK plugs on our CB1100s are evidence of that.

i don't think there is any regulation mandating 100K mile plugs. Most auto manufacturers tend to use them because they can cram more stuff into the engine compartment without worrying too much about the plugs being easily accessible. Since they only have to come out every 100K miles it's not as much of a big deal if the procedure is a bit more difficult.

Motorcycles definitely don't have that requirement. The standard NGK plugs on our CB1100s are evidence of that.
This is an interesting topic. I did quick search and it appears that spark plugs do fall within federal emissions warranties. But, not to 100k miles.

[TonUp_imp]

Does anyone know what the part number is for an Iridium replacement plug?
I figure if those standard plugs are so expensive, might as well pay a bit extra and get a long life plug.

[Motogeezer1949_imp]

I seem to remember in the video about the development of the bike that the motor was experiencing a hot spot around the spark plug area. I had assumed the solution to cool it down was the extra meat and fins where the plugs are. I'm guessing if one was to experiment, it would be wise to stick with plugs in the same heat range.

[furious_blue_imp]

I seem to remember in the video about the development of the bike that the motor was experiencing a hot spot around the spark plug area. I had assumed the solution to cool it down was the extra meat and fins where the plugs are. I'm guessing if one was to experiment, it would be wise to stick with plugs in the same heat range.

Ah, that's a very good point. I had forgotten that the CB has 'spark plug seat cooling'. I've never heard of any other production bike that has this (?). Probably best to stick to the specs on the plugs...

[the Ferret]

Honda did that to make the bike run as cool as a liquid cooled version. The hottest area was around the spark plugs in the cylinder head. There are actually oil passages which run around the spark plug seats inside the head, along with finned covers to direct cool air from above. The spark plugs are designed to not mess with these passages. They are long and narrow.

I reported on this back in Nov 2013

http://cb1100forum.com/forum/showthread....the+Wrench