Honda motorcycle oil funnel

Funnel/filler for 1970's Honda motorcycles, mine is a CB400F, the thread is M25 x 1.50. I hope at some point to put an air bleed pipe in, I have always used funnels in the past and could continue to do so …. but where's the fun in that?

I have now added a slot to allow the crankcase to vent during use.

Created on Fusion 360, printed on Anycubic Kobra 2 Neo using eSun PLA+

My next will be for my 1960's bikes which use an M24 x 1.5 thread.