H: Hubs, Wheels and Tyres Rear Drum Runout - what is an acceptable figure?

[Spqreddie]

Hello!
I am finishing rebuilding my rear wheel.
Unfortunately I didn't check the individual components before to start.... (Hub faces and drum faces and holes), but mounted all the parts as they were.

I have the following reading now. Are these acceptable?

Side 1:

• Side movement ( measured on the external diameter - Drum flange) = 18 cent of a mm (7 Thou if I got the conversion right!)
• Vertical (measured in the internal diameter of the drum) = 7 cent of a mm (2,7 thou)

Side 2:

• Side movement ( measured on the external diameter - Drum flange) =12 cent of mm (4,7 thou)
• Vertical (measured in the internal diameter of the drum) = 13 cent of mm (5,1 thou)
• Chain Sprocket mounded on drum on side 2= 38 cent of a mm (15 thou)

 

[greg brillus]

A common fault is the spoke flanges do not sit fully home on the hub flanges, this makes the drum sit crooked and not fully square.

 

[Spqreddie]

Thank you Greg,
I think it sit square, but as mentioned unfortunately I didn't measure before to assembly... so it's a visual assumption.

Now before, to take everything apart again, given the drum doesn't seems to be much out of line, I would like to know if the runout I have measured, is considered acceptable.

Thank you all!
Edmondo

 

[Gene Nehring]

A common fault is the spoke flanges do not sit fully home on the hub flanges, this makes the drum sit crooked and not fully square.

Last lot of a certain Australian suppliers hubs that I got were running out 10 thou or more on the faces. I believe he was getting them from a supplier in the UK.

 

[Gene Nehring]

Thank you Greg,
I think it sit square, but as mentioned unfortunately I didn't measure before to assembly... so it's a visual assumption.

Now before, to take everything apart again, given the drum doesn't seems to be much out of line, I would like to know if the runout I have measured, is considered acceptable.

Thank you all!
Edmondo

I think given the build up I was happy with under 5 thou on the faces of the drums after all the build up. I believe mine were at about 3 thou.

 

[vibrac]

Last lot of a certain Australian suppliers hubs that I got were running out 10 thou or more on the faces. I believe he was getting them from a supplier in the UK.

Yes generally there is a difference between the cheaper cast drums and those machined from a solid billet

 

[Bill Thomas]

Did I read somewhere the drums were dipped in paint ?,
So might have more paint in places ?.

 

[Gene Nehring]

Yes generally there is a difference between the cheaper cast drums and those machined from a solid billet

Might be cheap in the uk. They were not that cheap down here.

Casting a hub vs billet does not excuse poor machining. At least that’s the way it seems to me.

 

[Simon Dinsdale]

Yes generally there is a difference between the cheaper cast drums and those machined from a solid billet

Cast v solid billet has nothing to do with it. The critical surfaces are machined on both type and so both type could be machined right or wrong.

I find that if the drums has paint on the area where it contacts the spoke flange then the paint can built up around the edges and cause problems. Same with spoke flanges as the factory originals were cadnium plated so no paint build up, but if you have rusty originals and then blast and paint them then the paint on the contact face can cause problems.

Simon

 

[bmetcalf]

Would the issue of spoke bends touching the drum be happening here? Peter Barker used to offer washers to space things out, maybe the VOCSC does now.

Edit; They have a ring for the purpose PN H66