Compression test plug size?

[Guest]

The compression gauge I use for my '82 1100GL does not fit Tom's '80 1100E because its spark plugs are smaller.

Of course I only discovered this after taking the tank off to get the the plugs and removing all the plugs.

Looks like the 821100GL is 3/8"

What size is the 801100E?

Any suggestions for where to find an adapter in the city full of the usual shops?

If not maybe i will get these from Amazon. Looks like it will also fit my Honda E2000i generator.

edit: I did already check at my usual auto parts store and Home Depot. The compresison test guage I have is the Lisle shown here on Amazon

TIA,
-Bob

[Steve]

Yep, the 1100GL is an 8-valve engine with 14mm plugs.

The 1100E is a 16-valve engine with 12mm threads.

I believe all the 16-valve engines and the 8-valve 650 engines all use the 12mm plugs.

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