Singlespeed & Fixed Gear - Spoke gauge switch?
Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.
04-21-08, 04:22 PM
I have a a front drum brake I want to install and I'm thinking of switching from 14 ga to 12 ga spokes.I assume this would require larger holes in hub and rim.Can these just be drilled out.Thanks,Ron
04-22-08, 06:12 AM
Yes, but there could be serious consequences like the hub flange breaking apart.
What kind of hub?
Why do you want 12 ga.? Is this a tandem set up?
Despite conventional wisdom, bike theory suggests thinner spokes are stronger.
Straight gauge spokes have the same thickness all along their length from the threads to the heads.
Single-butted spokes are thicker than normal at the hub end, then taper to a thinner section all the way to the threads. Single-butted spokes are not common, but are occasionally seen in heavy-duty applications where a thicker than normal spoke is intended to be used with a rim that has normal-sized holes.
Double-buttedspokes are thicker at the ends than in the middle. The most popular diameters are 2.0/1.8/2.0 mm (also known as 14/15 gauge) and 1.8/1.6/1.8 (15/16 gauge).
Double-butted spokes do more than save weight. The thick ends make them as strong in the highly-stressed areas as straight-gauge spokes of the same thickness, but the thinner middle sections make the spokes effectively more elastic. This allows them to stretch (temporarily) more than thicker spokes.
As a result, when the wheel is subjected to sharp localized stresses, the most heavily stressed spokes can elongate enough to shift some of the stress to adjoining spokes. This is particularly desirable when the limiting factor is how much stress the rim can withstand without cracking around the spoke hole.
Triple-butted spokes, such as the DT Alpine III, are the best choice when durability and reliability is the primary aim, as with tandems and bicycles for loaded touring. They share the advantages of single-butted and double-butted spokes. The DT Alpine III, for instance, is 2.34 mm (13 gauge) at the head, 1.8 mm (15 gauge) in the middle, and 2.0 mm (14 gauge) at the threaded end.
Single- and triple-butted spokes solve one of the great problems of wheel design: Since spokes use rolled, not cut threads, the outside diameter of the threads is larger than the base diameter of the spoke wire. Since the holes in the hub flanges must be large enough to fit the threads through, the holes, in turn are larger than the wire requires. This is undesirable, because a tight match between the spoke diameter at the elbow and the diameter of the flange hole is crucial to resisting fatigue (http://sheldonbrown.com/gloss_e-f.html#fatigue)-related breakage. Since single- and triple-butted spokes are thicker at the head end than at the thread end, they may be used with hubs that have holes just large enough to pass the thick wire at the head end.
04-22-08, 07:50 AM
Well,at the risk of being kicked out of here,I have Micargi beach cruiser mounted with a 50cc.Chinese 2 stroke.I thought it may be prudent to put a drum brake hub on front.Ordered a Sturmey-Archer.I think 14 ga should be fine but I find weight is no longer an issue.Thanks,Ron
04-22-08, 09:36 AM
guess I'll stick with 14 ga.I did just receive brake hub.Absolutely no instructions.Could easily be mistaken for a heavy duty saltwater baitcasting reel.Geez,you need a motor to haul this thing around.Thanks,Ron
Powered by vBulletin® Version 4.1.12 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.