Rear wheel offset for a Dommie 99

I don't have a measurement ,but I set mine exactly between the rear suspension units .It steers beautifully and turns in very well. Others comment on it. Can't be far out .I would have liked a bit more clearance on the chainside as anything bigger than a 3.50 tyre will not fit.

Hi Tom - The Dominator rear and front rims are central on their respective hubs. So no offsets.  If the rear wheel is not central in the swinging arm you have problems with the brake-drum and spacers or a distorted swinging arm.  Good luck, Howard

RGM have a full break down of wheel off set AND they know what they are talking about

Hello again Tim and Tony,  I think that you will find that Roger has measured from the outside of the hub to the nearest part of the rim on that corresponding side.  These measurements will obviously vary depending on the size of the rim (WM!, WM3 etc).  If the measurements are the same from both sides what one can say confidently is that the rim offset is zero. In other words if you build your wheel with the centre-line of the rim aligned to the centre-line of the hub it must be correct,  irrespective of the rim width.  This is too hard to measure when the rim and probably tyre are fitted so I guess that Roger took the measurements as best he could.  My interpretation of offset is no doubt different to yours Tony but then I am only a simple Chartered Engineer who,  as you so kindly point out, doesn't know what he is talking about.  Kind regards, Howard   

Have to say that I agree with the guys above in that the rim is set to be bang in the centre of the swinging arm. Same for the front, bang in the centre of the forks.  That's how I built my wheels and the wheel alignment if perfect.  Not sure where RGM measured from as that just seems to cloud a simple issue.

off set . means the line from the centre of the hub to the centre off the rim. If the line is dead centre = zero off set 

with a straight edge running diagonal over the centre of the brake drum over the rim edges . if the hub is sitting lower than the rim that is negative offset

if your hub is protruding over the rim shoulder that is positive offset

MY interpretation wheel offset

The hub is not centre to the swing arm . the rim is adjusted so it sit centre to the swing arm. The swing arm is mounted so the centre is to the frame head stock

How I look at it.

Get the rear wheel spacing correct so as the chain alignment from sprocket to sprocket is as near as dammit, then centre the rim between the swinging arm by adjusting the spokes - no need for any understanding of off sets.

I use a 100/90 19 Avon Roadrider on the rear of my 99 with no clearance issues - although it is tight - just over an 1/8" each side.

The std size normally fitted is a 3.50x19.   The latest Avon SM is what I would use. .The old square profile has gone and its a long lived tyre  which  has  deep sidewalls .More Modern low profile tyres will lower the gearing and alter the way the bike sits on the centerstand.and sidestand, But that might be an improvement!.

When I built my 99 from wrecked remains I decided  it would be all original apart from some modern  " proper" tyres. I consulted the Leading Norton specialist who had worked on countless Nortons and restored a bike exactly like mine.  I ordered the tyres he recommended about half way thro the build. What could go wrong?.  Everything.  The tyres were way too big in width and were relegated to wall art.I stopped believing in self proclaimed experts. I went back to the tyres that God (Norton Bracebridge st) specified  and all is well.And my sons still have trouble keeping up with the old clunker.