Gearbox Oil

Posted by Hendred on
URL: http://silk-motorcycles.221.s1.nabble.com/Gearbox-Oil-tp5001455.html

We had a very interesting talk by a motorcycle engine/gearbox designer and repairer at our recent VOC meeting.  We got on to the topic of gearbox oils suitable for Velocette gearboxes.  His recommendation was MTF94 which was developed for Landover and some Rover model gearboxes.  The problem with EP80/90 oils is that some contain additives which attack the yellow metals in the gearbox which results in their rapid wear.   It is difficult to tell which ones have the additives as it isn't shown on the label.  Most commonly available EP80/90 oils are just labelled API GL4 or GL5.  There is an earlier thread in this forum which mentioned Silkolene BOA or Gear Oil Medium, both of which are API GL4/5 compliant but no information on additives.

As the Silk gearbox is based on the Velocette box and contains yellow metal bushes and selector arms I will be changing over to MTF94 as the possibility of accelerated wear from EP additives has concerned me for some time.

Be interesting to hear other views on this topic and experiences of yellow metal wear - if any.