Gearbox filler plug Allen size?

[AdzCM]

Just wondering what size of Allen bit I need to open the gearbox filler plug. Don't have a bit to fit, so will just order one. Couldn't really get the vernier in, but it was around 20mm?

Adrian

[hayesey]

17mm.  a wheel bolt head can be used if you don't have a hex key about.

[AdzCM]

17mm.  a wheel bolt head can be used if you don't have a hex key about.

That is pure genius haha. Cheers Paul.

Adrian