Hermle 340-020 floating balance with no speed adjustment

[John P]

I'm working on a ALFRY anniversary clock. Came in with a broken mainspring
on the time barrel. Replaced the barrel and spring.
The clock seems to keep accurate time.
This is the 1st one I have seen without a speed adjustment screw.
How is one to regulate the speed?
The balance wheel is spinning at 360 degrees.

John

 

[harold bain]

Pictures may help, but if it is an older balance, it has a three legged spider spring on top of the balance that is moved to regulate it.

 

[John P]

Thanks Harold,