V7 Special/Stone plug boots.

[pete roper]

Without looking at the NGK book or website Steve I can't remember what the differences are with the second letter for the caps. It might just designate a difference in the angle at the elbow. What I can remember is the suffix letter which relates to the top electrode fitting of the cap. F designates the larger electrode, E designates the threaded top. When fitting aftermarket caps it is sometimes necessary to change the plugs to fit the caps. Over here for instance you cannot get XD05E caps which means you have to swap to a plug with a different electrode fitting.

Essentially though as long as the plug has the right reach, thread and heat range it really doesn't matter if it has one electrode or two. Consult the book, match up the plug and cap, install, ride.

Pete

[stevet]

Thanks, Pete, I appreciate the input.

Steve.

[spowell]

So which plug cap is it:
MI's NGK XBO5F, or
Pete Roper's NGK XDO5F?

Is there agreement on the spark plug, NGK CPR8EA-9?

And where is the likely place to obtain the caps?  I've been web searching some of my local auto parts stores websites for that NGK part and they don't have them.  And it's too late on the Saturday afternoon to start calling local MC shops.

I'll email my local MG dealer and ask them about the tech update.  Closed til Tuesday, though.

Thanks,
Steve.

Here is what I could find on the difference between the XB and XD. Seems to be the plug diameter.



Image found here: http://www.sparkplugs.co.uk/ngk-plug-cap-xb05f

[Andy1]

Logically you would think that the XB05F caps were for a B sized plug....but a B sized (14mm) plug does not fit inside them.......while they fit the CPR8EA-9 plug perfectly.
And the plug cap fits down the hole in the cylinder fine.

Not installed mine yet as the originals are OK but it looks like the XB05F / CPR8EA-9 combination is right.

AndyB

[stevet]

Great info, guys, thanks!

Steve.