for the units fitted on the later GSs you need a special pump (£140 IIRC) to get high enough pressure. i've spoken to the importers about this, and there is no way round it.
other older(?) units run at a lower pressure & you might be able to do it with a substitute for their low pressure pump.
Spoke to Mr Fournales UK today , they have reduced the Price of the pump
drastically , cos it was affecting overall sales.
Yes you need it . But its now £49.00
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