Pin lever balance

[LittleWatchShop]

I have cleaned a BFG 866 and am timing it.  I notice that PU and PD I get wildly different timing than level.  So I was curious about the pin lever...is it balanced?  No...it is not--confirmed on a balance poising tool.

Then I found this old thread where some of you said that it is not supposed to be balanced.  This perplexes me.  Counter intuitive.

I am all ears!

 

[KarlvonKoln]

Following.  I want to find out more too.

[Nucejoe]

Pin lever is not a time keeping element, no need to be poised. 

Rate variation has to do with poise of the balance and to a lesser extent shakes on balance staff, rarely defective jewel. 

BFG 866 balance is old tecnology, the balance is likely to be causing the varaitions you see.

Regs