Does anyone know the thread pitch on an NC30 spark plug? I know they are 8mm, but I seem to remember having trouble cleaning the threads in my heads because of the pitch

Reason I ask is I want to buy something like this:
http://www.ebay.co.uk/itm/120933175121? ... 423.l26494

and I'd love to find one that just works, rather than having to get collars machined etc. Not interested in using the rubber bung style testers either.

Thanks
Luke

lukemillar wrote:Does anyone know the thread pitch on an NC30 spark plug? I know they are 8mm, but I seem to remember having trouble cleaning the threads in my heads because of the pitch

Reason I ask is I want to buy something like this:
http://www.ebay.co.uk/itm/120933175121? ... 423.l26494

and I'd love to find one that just works, rather than having to get collars machined etc. Not interested in using the rubber bung style testers either.

Thanks
Luke

I think it was 8mm / 1.25 but I cant be sure.

That kit from the US wont work.. the 8mm is the compression tester adapter hose size.. the actually plug sizes are 10mm/14mm and 18mm (cars and most bikes.)


It easy enough to make out of brass bar, if you dont have a lathe do you have any friends with one, its easy enough to knock one up.

I cut it from long brass bar and used an o-ring out of an assorted kit which works fine. If I had a lathe here id knock you one up.

I think they are quite scare as the only Honda bikes I know that use this size plug is the NC30 and NR750.

Honda should still the copmresion testester adapter but it was relally expesnive last time i checked hence making my own. 07KME-MR8-0100

8 x 1.0 mm

Ok... I know this is an old thread, but do you think this adapter will work?

http://www.toolsource.com/diesel-engine ... 97782.html

It will put a dent in the top of your piston! but if you cut the end down back to the threaded bit it should work.
I've just checked a plug with my pitch gauge and it is a 1.0 mm pitch thread. I've taken a a photo but as usual can't get it to work on this forum.

Thanks for the confirm. I might use an old plug as an adapter.

you can use the rubber push on type to get a compression testing reading too... that original link kit has them in, just make sure you get a long one :)