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spark plugs after 70.000 Km - Printable Version

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RE: spark plugs after 70.000 Km - DAC - 08-17-2026

So, having never changed the plugs or even take. Them out, at 32k miles and 11 years, I’m guessing it’s time to. My worry is messing up the holes since they’ve been in there so long. The plan so far is to use some penetrating oil, then getting the engine up to operating temperature, and a lot of patience to work them out.

Any other tips?

RE: spark plugs after 70.000 Km - Cormanus - 08-17-2026

Make sure you've thoroughly cleaned the area around the plugs so nothing can fall through the hole when they come out.

RE: spark plugs after 70.000 Km - DAC - 08-17-2026

Cormanus_imp dateline="0' Wrote: Make sure you've thoroughly cleaned the area around the plugs so nothing can fall through the hole when they come out.

Will do. Thanks!

spark plugs after 70.000 Km - max - 10-04-2023

For some reason we decided to have a look at the sparkplugs which are the original ones on the 2010 cb1100.

Something vitally importand on this bike is to clean any debris around the sparkplugs so as to prevent sand, small rocks and other hard things falling into the cylinder and " make themselves at home there " .

We pried some small loose rocks out of the cavity, blew around the sparkplugs before starting to loosen them, some loose grit came flying out with several blows in the small plastic tube, and also before the sparkplugs were completely removed some more loose stuff was "blown away", the second lot surprised me but there it is, easy to overlook this debris.

[Image: 83199e098d02fef42348dfdc8b210244.jpg]

and here are the plugs after 70.000 Km, the gap is 1 mm., the spec is 0.8 to 0,9 mm and i think i have gapped them before around 25.000 Km.
To me it seems fine for another 30.000 at least;

[Image: 2a9a6f1a999987dff24a2c77e405e94f.jpg]


and the tools i used to get them out and i used the smalles amount of 90w gear oil on the threads which helped a lot when putting them back in the engine, we"ll see if that was a good idea some time later;

[Image: be8138af8a672eccf9b3b5ae6dea6d2c.jpg]


So we think that removing them has some risk included because of the debris our bikes are prone to collect and it is easy to forget to blow the plugs clean before removing them, hope this helps.

RE: spark plugs after 70.000 Km - GoldOxide_imp - 10-04-2023

The plugs look good to me too, max. 100,000 kms should be reasonable.

Yeah, the classic roadway debris is always an issue when removing plugs from any engine. Even if the high tension leads have rubber boot/caps, I still find junk tends to fall down into the base area of the plug.

RE: spark plugs after 70.000 Km - pdedse - 10-04-2023

Hmmm...and to think the shop where I had my valves checked also replaced the spark plugs at 14k miles.

RE: spark plugs after 70.000 Km - the Ferret - 10-04-2023

I replace mine (and the air cleaner) approx every 25,000 miles (40,000km). Just put in my third set just before the CB 1100 rally this year.

RE: spark plugs after 70.000 Km - peterbaron - 10-04-2023

I replace my spark plugs and air filter, all OEM, every 50K kms.
They always look almost like new.

RE: spark plugs after 70.000 Km - GoldOxide_imp - 10-05-2023

For the Honda Africa Twin, over 100,000 kms. Some sort of [newer gen] iridium is used.

RE: spark plugs after 70.000 Km - peterbaron - 10-05-2023

Very sure my plugs would last 100K+ kms, and the reason I dont keep them that long in service is air cooled engine and higher chance of failure, which I don’t need during long distance rides,
Biker