Plug gap please?

Just gapped my plugs on the 850-T3 Cali to 23 thou as per Haynes.
The yellow Guzzi book say 19 thou.
Which is correct?
All the best,

23 thou

Thank you Keith.
All the best,

As Keith says for standard NGK plugs (about the best IMHO)
Always worth checking them against the cylinder head to see that this setting is giving a fat blue spark. Not terribly scientific but…
Usual rules on earthing the plug apply
All the best

Just to be obtuse, 20 thou

Make sure you do NOT get Thou" and mm mixed up
for the 850 and 1000 engines the HAYNES clearly shows

0.6mm or 0.023" plugs high speed 0.5mm 0r 0.019"

Tappet clearances are 0.22mm or 0.009" (see also the "Raceco reccomendations)Some Guzzi manuals will have the tappets as low as .10mm inlet and 0.15mm zorst and folk wonder why they run badly

Many Guzzi clearances ARE in METRIC folksguzzibear2013-08-07 12:28:54

Yes so my 20 thou then becomes 0.5mm, (pedantic: 0.508) I knew 0.5 should be a familiar number.
Mike H2013-08-06 14:52:45