Commando 750 rear wheel off set

Its all here

http://www.nortonownersclub.org/support/technical-support-commando/wheel-offsets

As you have a wider rim you need to modify all figures accordingly.

I then installed the rear wheel:-

• The spoke flanges are offset 1/8" to the left as mounted in the arm, so the rim is laced off 1/8" to the right to put the tyre in the centre
• The centre of the rim is 3.3/8" from a straight edge laid across the brake drum (not the backing plate

Hi peter. Some time back I wrote up a method of getting the rim to be perfectly central in the front forks and swinging arm in relation to the centre line of the bike...(which is wht you want) perhaps try this method as shown in the following write up....You will obvioulsy not require to do the front wheel but the second part will provide a way to get YOUR frame and wheels aligned...whic is better than any official measurement:

For the front wheel: With the old rim removed....Fit the wheel hub assembly with its spacers and tighten as if fitting a complete wheel. Cut a strip of cardboard, wood or plastic that fit exactly between the forks and measure the distance to find its centre...Now,.. say you are fitting a WM2 rim with 69mm width; Mark the centre of the cardboard strip and measure 69/2mm from this centre mark each side of it and once again mark the strip at these positions. The two marks will represent the rim edges ...(they should be equi-distant from the ends of the strip). This will be where you want the rim to sit. Hold the cardboard between the forks and flush with the side of the hub. Now, using a chosen solid feature on the hub for a reference, measure the distance to the rim mark on the cardboard. This will be the offset you require when building the rim. Usually the face of the brake drum is used by the wheel builder, so if you have used say the spoke flange to measure from....( the spoke flanges are easier to get a reference onto the cardboard strip rather than the brake drum face).... simply mark on the cardboard when you have it in position where the spoke flanges are....then remove the hub. By using these spoke flange marks, you can now reposition the cardboard strip to the hub and THEN measure the distance to the brake drum face to the rim position on the strip using a set square for accuracy. For the rear wheel, this is not so easy as often swing arms are not always equal distance from the bikes centre line, IE: the swing arm is not symmetrical in order to provide chain clearance....So, as before fit the rear wheel hub axle assembly with correct spacers and speedo drive if fitted, pushing it all the way forward in the slots and make sure hub is directly facing forwards and not skewed to the side. Tape a bar or piece of wood across the frame directly above the rear hub...Make sure the bike is level by using a spirit level across the rear frame. Now you have to find the centre of this piece of wood/bar....I would then use a laser line and shine this down the bikes top frame tube or use a straight edge from the steering column tube then mark the wood cross piece's centre. Then drop a plumb-line down from this centre mark to the hub and mark with a felt tip pen this position on the hub...Remove the hub assembly. The mark will represent the centre of the bike and the wheel on the rear hub position. Then using the cardboard measure used previously, you can line up the centre of the 69mm cardboard marks (If WM2 rim is used) to find where the edge of the new rim should be. Use a convenient flat edge on the hub on any side of the hub (usually the brake drum side) for the reference and measure to the cardboard mark this distance which represents the rim edge . Note the distance ...This measurement will be the rear wheels offset for your wheel builder....Les

Your offset is 3 3/8" minus (76mm divided by 2) to edge of rim or 3 3/8" to rim center, but I prefer setting up as per Les.

I have a WM3 rim that is 76mm wide, I've just been out to my bike and measured it. The dimension you want is 2.5mm. so with the rim on the kitchen granite work surface (and the wife locked in the cellar) you should be able to slip a 2.5mm drill or feeler gauge under the face that the drum butts up to.