Don't have blind faith in what you read in any of these sites, in regards to MVVS engines.

These engines have lately (three years ago) had their thread sizes changed.

The .40-.49 engine now have a 7 x 1.0 mm thread.
The .61-.91 engine now have an 8 x 1.25 mm thread.

If you get an older MVVS of these sizes, it may still have the older 6 x 1.0 mm thread.


So before believing and taking things for granted, take your vernier calipers and measure it yourself.