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Lacing Triumph 500 (to 1974) and 650 (to 1970) Rear Wheel (Rim 37-1007)

You will need:

A Triumph rim 37-1007, or equivalent, rim pierced to accept .300″ diameter nipples.
A set of 40 spokes:
- a. Buchanan part #Tri511 (specify Chrome or Stainless spokes and nipples)
- 10 spokes 7 9/16″ long with 95 degree head – left (drive) outside
- 10 spokes 7 9/16″ long with 90 degree head – left (drive) inside
- 20 spokes 7 7/8″ long with 90 degree head – right side inside and outside.
- 40 .300″ diameter nipples. Buchanan part number N10307.
Screw driver or modified offset-screw driver (picture below).
Spoke wrench.
Nipple lubricant.

Where to Start:

Verify that the holes pierced in the rims and the nipples measure .300.”Using a .250″ nipple in a .300″ hole can lead to wheel failure!
Lubricate the spoke threads using Buchanans lubricant. Lubricate the head of the nipple on the edge that bears on the wheel rim.
Place four nipples in rim as illustrated to identify how the rim is handed. This (37-1007) rim is handed and must be installed correctly.

This is a picture of a .250″ nipple in a .300″ hole. The nipple should fill the the hole in the rim! Using a .250″ nipple in a .300″ hole can lead to wheel failure!

Modified “Speed Driver” and 8″ Spoke wrench. Both save time and make the job easier, especially if your job is building wheels.THIS RIM (37-1007) is handed and must be installed the right way around! The rim is handed because the wheel hub has different diameter spoke flange holes on one side from the other.With practice you should be able to see the difference in dimpling and piercing that makes a rim handed. If you need some help try the method below:

In the picture I have placed nipples in the rim and I am measuring the distance between two adjacent nipples which are angled, front to back, away from each other.
Using the outside edge of the end of the nipple I get a measurement of 3″ (see picture below).
I then move to the other side of the rim and take a measurement on the a pair (it will be in the range of 3 1/4″).
By measuring the distance between the nipples you can determine which has a larger included angles.
From the angle you can determine which way the rims should be installed. The widest distance between the tops of the nipples (3 1/4″ in my case) goes to the drive side.

1
Time to offer the first, or “key”", spoke. It will be the drive-side outside and it is located like this: (On some early hubs there is a little half moon cut next to the “key” spoke hole.)

2
You take the first key spoke(7 9/16″ – 95 degree head) offer it to the hub and rotate it anti-clockwise like this (then follow with other 9 spokes). Your wheel will look like this:

3
Next you take the last 10 drive side spokes (7 9/16″ – 90 degree head) and offer them like this:

4
Time to move across the hub to the right side. You offer the third set of 10 spokes, (7 7/8″ – 90 degree head angle) like this:

5
The last set of 10 spokes, with the (7 7/8″ – 90 degree head), are offered like this:

6
Here is a map of where the spokes go. If you look you can see that the wheel hub flange closest (TS) is smaller diameter than the far side (DS) flange.You should also be able to see the the two spokes on the small flange TS – nearest the camera) are nearly parallel while a similar pair on the other side are not.If the rim was mounted wrong way around the spokes would have to bend for the nipple to be able to seat in the rim. If your spokes bend as they enter the nipple, the rim is on backwards.

Problems to look out for:

Many modern replacement rims are a lighter gage than the original Jones and Dunlop. One should be sure to lubricate the underside of the head of the spoke nipple where it bears on the rim. This is especially important when using stainless nipples as they are prone to galling against the rims steel. One must be extra careful when using stainless nipples in a stainless rim. Lubricate the parts well before assembly and stop if the spoke stops getting tighter as you turn it.
Buchanan lists the spoke torque on the insert in their spoke packaging as such “For large displacement cycles, the torque should be in excess of 80 inch pounds. Hub and rim structure will determine the amount of torque that can be exerted.” The key to reading this sentence is “Hub and rim structure will determine the amount of torque that can be exerted.” See the brake drum in picture below. The spoke tension broke the cast hub.
Applying too much torque to a spoke can lead to failure. While the nipple can through the rim the cast hubs can also fail. This is a 1967-70 Triumph front hub.

Triumph IS NOT A LARGE DISPLACEMENT MOTORCYCLE as described in Buchanans instructions! The final torque using an aftermarket Triumph # 37-1007 rim would be more like 30 to 35 inch pounds. This can be a little bit tighter if using original Dunlop or Jones rim.
Definitions:

Key Spoke: The first of the ten spokes offered to the hub. In this case it does not refer to the spokes next to the tube hole in the rim.
Keyhole: The unique keyhole shaped spoke peircing on the TS hubs flange.
Cross Pattern: This wheel uses a cross three on both sides.
Dimple: The bulge pressed into the rim to accept the nipple. This rim is what is called 1×1 where the dimples alternate from one side to the other every other dimple. The front wheel for this bike uses a 2×2 pattern. This is where two dimples are on one side followed by two on the other side.
Piercing: The hole in the dimple for the nipple. There are three common sizes: .250″ and .300 used on British wheels and .281″ used on Japanese wheels. You should never use a nipple smaller than the piercing!!!
Drive Side and Timing Side: Refers to the side of the motorcycle. On this motorcycle the drive side is the left and timing side is the right side.