Modifed front brake plates

http://victorylibrary.com/brit/2LS-table.htm

Jeffrey diamond.

Interesting articles and stuff on here!

 In the Table below, the brakes are grouped by drum ID, then sorted by index of efficiency with strongest first. A link appears next to the description, click to see a picture of that brake (some links are not functional yet). Terms used mean:     “*”: converted to 2LS.     “K”: weight of the assembled hub in kilograms.     “S”: # of spokes in the hub.     “A”: axle diameter in MM.     “Brake Shoe”: lining width.     “Drum Type”: number of leading shoes and drums.     “Area” (swept area): brake drum ID × shoe width(s) × Pi, in square inches.     “R”: ratio     “BEC”: brake effectiveness coefficient     “ß” index of efficiency     Ratio is a “leverage factor” (developed from a Mac program by Douglas Wright) which weights the effect of replacing the trailing shoe with another leading shoe. The improvement of the single shoe is 27.9%, therefore: Ratio “S” = SLS & dual SLS at 1.0000, Ratio “D” = 2LS & 4LS at 1.1395.     BEC: swept area × the drum radius.     “ß”: BEC multiplied by the Ratio to give an arbitrary relative strength rating for comparison.

Copied from Victory Library Jeff diamond.

Results of Drum Brake Tests:

In Index of Efficiency B; 30% factor normal road riding, 40% factor performance/Road racing

Norton brakes Atlas 88/99 come in at  B = 126, barely adequate @ 30% weight Machine chassis weight factor;

Commando B =  TLS 143

BSA Triumph Full width/Conical TLS B = 186;

The Gold Star standard brake comes out B = 121, with a Pearson 2LS conversion this increases to B = 138! The main problem with the Norton set up seems to be the reduced Brake shoe area compared to BSA Triumph set ups, as the brake shoe with @ 1 1/4 inches is smaller that 1 1/2 inches BSA/Triumph twins/Triples and the BSA Gold Star @ 1 3/8 ths.

Se  attached Table which relates efficiency to Mph!