12 string string tensions

[Brian T. Williams]

Hello, hope everyone is keeping safe & well.

I have a Guild Starfire 1V 12string, 3 years old with a set, three piece (reinforced) neck.

I have recently re-strung the guitar from Ernie Ball 09-46  to a slightly heavier Rotosound 10-48, which I do prefer. I have tweaked the truss rod slightly (1/4 -1/3 turn) to compensate.  The relief is perfect, as is the intonation and tuning stability. The guitar plays fine and (to my ears), sounds better too; all the results I was looking for!

My only worry is the increased string tension, that has gone from 97.7Kg to 123.68Kg, (calculated with Stewmac's online string tension calculator).

I want to keep the guitar at concert (A440) pitch, but also, I do not want to risk any potential damage to the guitar, so my question is..............

Is a string tension of 123Kg. within the the acceptable parameters of a well constructed & very sturdy 12 string?

I have contacted Guild (Cordoba Music) regarding this, but meanwhile, I have had some excellent advice here before and I truly respect and value your opinions........any thoughts would be greatly appreciated !

Thank you.........Brian

[Rob Bixler]

Just as an anecdote. My neighbor who plays 3 chord folk songs on a Gibson B45-12 keeps his guitar tuned down one full step and plays it with a capo on the second fret. Someone taught him this near the time he bought it new. The mid 60s guitar is in great shape both top and neck angle.

[Paul Verticchio]

That gauge of strings should cause no temporary or permanent performance issues to your Guild Starfire XII. 
The guitar is designed and manufactured to easily accommodate a set of .010’s.  
Enjoy that beautiful 12-string and best of luck. 

[Brian T. Williams]

Thank you both, much appreciated.