Measuring wheel runout

[Steve_T]

Does anyone know how I should measure the run-out on a bike wheel, or alternatively
who I could ask to do it. I'm potentially looking at a set of wheels for the Falco,
but I'd like to avoid a costly mistake and know how to assess the condition of wheels
properly before I hand over any cash.

The seller seems keen for me to hand over a bunch of notes and take the wheels away to be assessed, however that makes me think of what could happen should I find the wheels are not true and the seller does not wish to return the money. I'm hoping some of the trackday specialists such as fergus et al might have a suggestion of how to do the assessment in front of the guy.

Thanks,

Steve.

[mtbr]

Mount the wheel in a static balance frame and turn it. Put something close to the rim (like a pencil) to give you an index.
If you want to be really precise, use a dial gauge instead of a pencil.
Look at the rim side to side and radially.

Personally I would be more concerned about cracks than run out, in wheels with an unknown history.