Spokes for the Ordinary (Penny Farthing) Bicycles
One Mans Opinion
Penny Farthing spokes are a frustrating issue for some riders. They are consumables. Frequent spoke breaks cause riders to carry spares in large numbers in their wheel strapped to the inside. Generally this happens on reproduction bikes or on restored bikes with a total set of new spokes. This should not be the case. Some original bikes from the 1880s still have all of their original spokes. If some bikes' spokes can last for 120 years, why not new spokes? Original bike makers worked hard and studied the issues for many years. Most changed from Radial to Semi or Full Tangent spokes by the late 1880s. They had the best mechanical engineers in the world in the bike industry. The late 1880's bikes reflected the results of their research. There were several techniques which they adopted:
- Butting spokes (variable guage...thicker at the hub for about 2 cm) allowed a thinner section for the rest saving weight while increasing strength.
- Tieing and soldering added strength
- More Crosses (a 5, 6, or 7 cross pattern) added strength and can facilitate a wheel with slightly thinner spokes.
- Columbia Light Roadster had 1 cross in 1885 and went to 3 later for strength
- Victor had 3 crosses in 1885 and went to 6 crosses by 1890 for strength
- G&J Light American Champion (Some say the Best US bike) had 7 crosses
- New Rapid (Some say the BEST ordinary) had 7 crosses
- New Mail had 3 crosses...as did its English mate Royal Mail
- Rudge had only 3 crosses BUT
- The spokes were butted which made for a stronger wheel...as above.
- The spokes were threaded with all spoke heads on the inside of the hub flange which made for a stronger wheel than if some were on the inside and some on the outside. RUDGE WON THE MOST RACES.
- Andrews had only 2 crosses...BBBUUUTTTTTT:
- Direct pull spokes (like Andrews) have no loop to be stressed at the turn in the hub...since no turn is in the spoke at the hub flange. Rather the Flange turns and the spoke goes happily straight through to the nipple at the rim.
For most wheels a 12 guage spoke wire is the best choice for strength and weight. See the table at the end of the article for spoke guage definitions and suggested applications. The European 2.6 Millimeter is best for a match to the 12 Guage which I generally recommend. Actually 12 guage is 2.68 mm. Therefore one would want to do the threading of the 2.6 mm with a ROLLER rather than cutting threads. This way the spoke will be a TIGHTER fit into the 12 guage spoke nipples. This is a good way to make sure that the spokes are not easily coming loose. If they come loose and are ridden loose then the spokes are being flexed far too much and the loadings are uneven and will cause early spoke failure.
Also, when heading spokes for the connection at the hub, you should never heat the spoke. Heating takes out the work hardening of the steel which was added in the drawing process of the spoke. The heat would also leave the spoke very vulnerable to fatigue from flexing.
Of course, stainless steel (although shinny and bright and therefore popular for looks) is a bad spoke wire choice for riders because:
- It is more brittle and therefore more easily fatigues at the flange and breaks.
- It will not easily roll threads.
- You cannot tie stainless with fine wire at the crossings and then solder to have the ties stay tight. The solder will not hold to the stainless after a few rides.
- Heading is difficult without adding heat...thus spoke heads are weaker on heated stainless steel spokes.
Thus you want to use a good grade of zinc coated (~1 mil) 12 guage steel wire which will work well and not fatigue quickly under the stresses of repeated flexing at the turn through the hub flange. If the expected loading is over 220 lbs then a stronger (heavier guage) spoke should be used. In doing the bending at the flange, you want to be sure that there is a nice fit...no pocket of air (bowing) which will flex repeatedly...then snap.
A fun observation in the following wire guage table: the 37 guage wire will allow 1 Lb of wire to unwind for nearly 1 mile ( nearly 5280 ft).
Cycle Recycled Cycles,
Steve
| Wire Gauge No. | English Measure
Decimal | Millimeters | Feet
Per pound |
|---|
| 3/8" | 0.3750 | 9.520 | 2.66 |
| 5/16" | 0.3125 | 7.940 | 3.84 |
| 1 | 0.2830 | 7.190 | 4.68 |
| 2 | 0.2625 | 6.670 | 5.44 |
| 1/4" | 0.2500 | 6.350 | 5.99 |
| 3 | 0.2437 | 6.190 | 6.31 |
| 4 | 0.2253 | 5.720 | 7.38 |
| 5 | 0.2070 | 5.260 | 8.74 |
| 6 | 0.1920 | 4.880 | 10.16 |
| 3/16" | 0.1875 | 4.760 | 10.70 |
| 7 | 0.1770 | 4.500 | 11.95 |
| 8 | 0.1620 | 4.110 | 14.27 |
| 5/32" | 0.1562 | 3.970 | 15.37 |
| 9 | 0.1483 | 3.770 | 17.03 |
| 10 Best size for Lowell Noel @ 175 Kg | 0.1350 | 3.430 | 20.55 |
| 1/8" | 0.1250 | 3.180 | 23.94 |
| 11Good for JUMBO RIDERS over 220 lbs (over 100 Kg) | 0.1205 | 3.060 | 25.79 |
| 12 Best for Ordinary Spokes! | 0.1055 | 2.680 | 33.65 |
| 13 OK for riders under 170 lbs but 12 guage is better | 0.0915 | 2.320 | 44.73 |
| 14 This will break often if riden on roads with "spray and chip" surface | 0.0800 | 2.030 | 58.52 |
| 15 For Racing on Wood Tracks Only | 0.0720 | 1.830 | 72.25 |
| 16 Racing on Wood Tracks Only by Bantem Weight Riders (under 55Kg) | 0.0625 | 1.590 | 95.88 |
| 17 | 0.0540 | 1.370 | 128.40 |
| 18 | 0.0475 | 1.210 | 166.00 |
| 19 | 0.0410 | 1.040 | 222.80 |
| 20 | 0.0348 | 0.880 | 309.30 |
| 21 | 0.0317 | 0.810 | 372.70 |
| 22 | 0.0286 | 0.730 | 457.90 |
| 23 | 0.0258 | 0.660 | 562.70 |
| 24 | 0.0230 | 0.580 | 708.00 |
| 25 | 0.0204 | 0.520 | 899.90 |
| 26 | 0.0181 | 0.460 | 1143.00 |
| 27 | 0.0173 | 0.440 | 1251.00 |
| 28 | 0.0162 | 0.410 | 1427.00 |
| 29 | 0.0150 | 0.380 | 1665.00 |
| 30 | 0.0140 | 0.360 | 1911.00 |
| 31 | 0.0132 | 0.340 | 2149.00 |
| 32 | 0.0128 | 0.320 | 2286.00 |
| 33 | 0.0118 | 0.300 | 2690.00 |
| 34 | 0.0104 | 0.260 | 3463.00 |
| 35 | 0.0095 | 0.240 | 4150.00 |
| 36 | 0.0090 | 0.228 | 4624.00 |
| 37 | 0.0085 | 0.216 | 5184.00 |
Note: The Westrex cutterhead uses 39 guage wire in the drive coils, and 45 guage in the feedback coils. The 45 guage is thinner than a human hair, and delicate to wind.