1960 A10 Super Rocket Rear Wheel offsets

[Craig]

Hi Folks

Apologies as this may well be a repeated topic but am struggling and bit and need some assistance.

I am looking for the rear wheel offsets for 1960 A10 Super Rocket. The rear hub (42-6313) is a 7” full width cast iron hub.
The new rim is 19" x 2.15 (CWC Stainless Steel).

I read a lot of topics stating no offset, however when I measure the existing rim I get about 8mm each side. I have no idea if the existing wheel is correctly built and judging by some of the other work on the bike, do not trust it at all.   

Appreciate any help you can give.

Thanks

Craig

[Jules]

Hi Craig, there are lots of discussions around wheel alignment and offsets in the forum, but I think the over arching discussion always plays out to ensure front/rear wheels align as the first and most important step (allowing for the different rim width f/r of course). In my case for example, with the front wheel centred and rear wheel aligned, the rear wheel "offset" within the swinging arm is a few mms side/side (cant remember exactly now).....

[JulianS]

With the full width iron hubs the centre of the rim should align centre line of the hub.

The was a very useful service sheet posted here earlier this year but cannot find it.

[Norsa1]

The best way is to run a laser down the backbone of the frame.  The laser is dead centre of the steering head and this allows the front wheel and the rear wheel to be aligned. Riding with some of the other bikes in the group their bikes are going down the road sideways.  Align your wheels with a laser and lace the read wheel to the centre line of the frame.

[muskrat]

G'day Craig.
This is the service sheet download JulianS mentions https://www.a7a10.net/forum/index.php?action=dlattach;topic=13967.0;attach=46476
Looks to me as saying central to drum.
As Norsa1 said it should be inline with the c/l of the frame.
Cheers

[Jules]

Hi Musky/Julian, I think there's a bit of confusion here....the service sheet isn't clear wrt its meaning/interpretation (at least from my perspective!!). I have a 1956 s/a full width rear hub (I think its referred to as "ariel type??) and when I look on this sheet it says "1 23/32 to C/L of rim from ballrace face on brake side", so not totally sure that's c/L of rim to C/L hub, plus its not really clear which MY the different wheel part nos. correspond to (I have no idea what the specific part nos. of my wheel rims are)??
AND I think the original question relates to C/L of rim to C/L of s/a, which could be different again (I think!)….
PS which front wheel spec should I be reading on this sheet too?.... I'm not sure that this sheet really helps unless you know which specific rim part no. you have actually now fitted

[RDfella]

As per Julian's post - and as I recall -  the offset is neutral, ie centre of rim with centre of hub (no offset). I think some posters are getting confused with wheel alignment. Or is it I who am confused???

[JulianS]

The iron hub front wheels are parts 42 5806 for A7, 42 5803 for A7SS and A10 Golden Flash, and 42 5804 for Super Rocket and rear 42 6398 and 42 6338 for SR are built with rim central to hub.

Not to be confused with the Ariel type.

[muskrat]

G'day Jules.
The 56-57 "Ariel" hubs are front 42-5600, rear 42-6088. Not on list above.
I'm pretty sure the c/l of rim IS central to c/l of hub (spoke flanges). I'll check tomorrow as I have to dig it out and cram a few more bikes into the shed ((garage for a house sale inspection. Wish me luck) wonder if I could put it in the for sale section)).
G'day Rd.
If the steering head is central and the front wheel is central in the forks the rear wheel is central to the frame ( not the s/a). But the s/a in a 56-57 IS central to the frame. Mine handles great enough to come 1st in the B grade (how fast do you want to spend) State Champs two years running.
I don't have a later model to measure.
Some HD's come std with a 15mm offset front to back 
Cheers

[ironhead]

Hi Folks



I read a lot of topics stating no offset, however when I measure the existing rim I get about 8mm each side. I have no idea if the existing wheel is correctly built and judging by some of the other work on the bike, do not trust it at all.   

Appreciate any help you can give.

8 mm each side must mean it's central. If you are building a F/W iron hub wheel & all the spokes are the same length ( which from memory these are) the rim needs to central to the hub. Doesn't matter weather you use a WM1 / 2 or 3, the key is center of the rim to the center of the hub.
Hope this makes sense.