Were all genuine Connoisseur BD1/2 turntable belts the same?

Were all genuine Connoisseur BD1/2 turntable belts the same?

I had noticed over the years differences in drive belt diameter but never measured them before, no need to, just buy replacement genuine parts.  Things are different now with T&G gone, nothing lasts for ever even though we would like it to.

The following comparison of genuine belts comes from my personal stock.  One of the belts I purchased from T&G before they ceased trading and the other is from a BD1 Kit from Sugden, possibly one of the last kits they sold.

Sugden belt from BD1 kit:

On the right is the T&G, on the left is the Sugden:

1. Supplier: Technical & General

Belt diameter: 2.14mm +/- 0.01mm

Belt speed: On both 33 1/3 rpm and 45 rpm belt runs very slightly fast.

Belt length: 830mm approx.

2. Supplier: Sugden, from a new old stock BD1 Kit, maybe the last they made.

Belt diameter: 1.9mm +/- 0.01mm

Belt speed: 33 1/3 rpm and 45 rpm belt runs slightly slow.

Belt length: 815mm approx.

My observations on the belt running:

Both ran well and changed speed effectively.  Both ran quietly but the T&G thicker belt rubbed slightly on the pulley 45rpm groove sides making a low level rubbing sound even when pulley adjustment was correct.  The thicker T&G belt was slightly stronger when stretched as to be expected but both drove the platter effectively.  The two belts looked to be made of the same natural black rubber with a very elastic feel to them, an important property for decoupling motor noise.  Genuine belts are ground rubber and appear vulcanised at the join.  As can be seen in the photos, the thinner Sugden belt has grinding which has left it very coarse, kind of scaly looking compared to the T&G belt which has a finer finish.

Which do I prefer? The thinner Sugden belt - for the reasons above, I am more comfortable with how it runs.

This seems a bit of an indulgence given that you can’t buy them anymore, but when we look to substitute them we should remember that they weren’t perfect.