The three decisions behind an FHR: the 20 or 30 degree recline angle, the collar measurement that sets your size, and the posts, tethers and clips that connect it to your helmet.

The three decisions behind an FHR: the 20 or 30 degree recline angle, the collar measurement that sets your size, and the posts, tethers and clips that connect it to your helmet.

A customer asked whether he needs a 6x74mm boss for his Personal wheel or a spacer. The answer depends which M3 he has. Here are the two bolt patterns, which hubs are drilled for both, and the two spacer sizes that will not do the job.

The five decisions behind a race helmet in the order they arrive: standard, full face or open face, shell material, intercom provision and size, with the full price ladder from £309.60.

The HM is BC Racing’s remote reservoir series, built for sustained track use. 42 fitments across 8 makes, and one install note BMW buyers need to know.

The nine helmet standards Motorsport UK accept for national events, what the FIA 8859 and 8860 families mean, where Snell fits, and the one standard on the list with an expiry date.