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Norton Commando
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08/11/24
Norton Commando
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10/05/24
Norton Commando
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09/21/24
Norton Commando
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08/30/24
Norton Commando
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09/21/24
Norton Commando
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04/29/24
Norton Commando
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05/04/24
Norton Commando
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06/13/22
Norton Commando
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Updated 10/08/24
Norton Rear
Wheel Lacing
Updated
04/03/24
Norton Front
Wheel Lacing
Updated
09/21/24
Norton Front
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Updated
09/21/24
Sunday, December 22, 2024
January 29, 2019 I'm building a 1974 850 Commando, and both wheels need new rims. So, I'm going to build them with new rims and spokes. Before taking them apart, I am documenting the measurements and I'll detail it all here. This page covers the front wheel.
Norton front disc brake wheels are harder than most to assemble and true. The rim is not centered on the hub, and the spokes on the disc side have very little angle to the rim. This makes getting the offset difficult.
The rim is More complicated than normal. The picture shows the old built wheel and the new rim with the hole for the tube aligned. When we start lacing, we'll start with the non-disc inner spoke and go to the fourth hole.
There are 10 each of four different spokes. The longer are non-disc side. The more square are outer.
The offset from the hub to the rim is 0.500" on the disc side. On mine, the other side is 0.831" but that will be ignored and 0.500" will be used as shown in the first picture.
January 30, 2019 Ok, time to take the old wheel apart, polish the hub, and then start building.
January 31, 2019 Here's the hub ready to go below. It was hard to get to this condition. First used #0000 steel wool, then the parts that could be done using my buffer, and finally by hand. It took about three hours.
February 2, 2019 Still stuck without the correct spokes for the rear wheel so back to the front. In the first picture, the inner spokes are installed. They were partly tightened to make sure they were the correct length and the loosened so the outers could be installed
In the second picture, the outer spokes are installed and the first round of static truing is done.
By static truing, I mean that the hub offset is very close, and the rim is equidistant from the hub (centered). This is all done with the disc side. The disc side spokes have very little angle from the hub to the rim and slight turns of the nipples makes big changes. To start, the non-disc side nipples are tightened to about 4-5 threads showing and the disc side 1-2 threads showing. Then the offset and centering are set using just the disc side spokes with the office around 3/8" (will be pulled to 1/2" later using the non-disc side spokes).
On this wheel I decided to install the bearings after the wheel was nearly trued and cleaned up. Generally, it's better to install them first so you can use the axle for measuring center and of course, they need to be there for a truing stand or to true on the bike. I've had so much trouble with the rear wheel spokes causing me to take it apart a few times and getting grease and anti-seize on my hands and then on the hub. With the bearings installed, it's much harder to cleanup the hub.
February 4, 2019 After searching for hours I found the double row bearing I set aside for this wheel and installed the bearings.
February 6, 2019 The disc side is trued and the spokes are nearly tight enough. Notice the arrow - it's hard to see, but the gap is 1/8" and it will be pulled to 1/2" when the non-disc side is tightened. Right now, the non-disc side is just finger tight. The outside disc side spokes set the side to side offset and the inner disc side spokes set the center offset.
February 9, 2019 Back on this wheel. I decided that it would be nice for this page to know actual torque values so I bought a spoke torque wrench. It is simpler when you don't really know!!
Various info says that the torque on the disc side should be 40-50 inch pounds in-lb (4.5-5 newton meters (N-m) and the non-disc side less, maybe 25 in-lb. My wrench is much easier to read in N-m so I'll talk that way and state the final in-lb at the end.
I tightened the disc side to 3 N-m and made sure the wheel was still true. Then, planning to go a little at a time, I tightened the non-disc side to 1.5 N-m. The wheel was still true, but my offset was 5/8"! So, I tightened the disc side to 5 N-m and the offset barely moved, So then, I tightened the disc side to 6 N-m and the offset was slightly more than 9/16". Clearly, it wasn't going to be possible to get back to 1/2".
So, I loosened all non-disc side spokes until loose. The disc side spokes were then not overly tight. I tightened them to 4 N-m and the offset was then minus 1/16".
Then I went around the rim tightening the non-disc side a little at a time checking for true all the while. Then I tightened all the non-disc side to 0.5 N-m. This brought the offset to a little less than 1/4" while still true. Then I tightened to 1 N-m and the offset was about 3/8" with a little wobble so I re-trued. Then I tightened to 1.5 N-m and the offset was just under 1/2" and still fairly true. Very small changes on the non-disc side makes a big difference in the offset so I tightened all to 1.75 N-m. This brought the offset to exactly 1/2" with a tiny bit of wobble.
Finally, I carefully trued by tightening as needed and I verified the offset at several location around the rim.
I tested the torque to see where it ended up on the disc side. It was 5.75 N-m (51 in-lb). Keep in mind that they were tightened to 4 N-m before I started on the non-disc side. So, with this rim, these spokes, using anti-seize, the procedure ended up being:
Tighten the disc side incrementally to 4 N-m (35 in-lb). Probably best to do 1 N-m, then 2 N-m, then 3 N-m, and finally 4 N-m.
Tighten the non-disc side incrementally to 1.75 N-m (15.5 in-lb). Yes, it sounds light, but any more and the offset is too large. Also, since anti-seize was used on the threads and grease under the nipples, they are tighter than the torque implies.
Touch up the truing (tighten only).
February 21, 2019 Mounted the tire and installed the disc so this wheel is done except balancing so back to the
74 Norton rebuild page.
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