If like me you've had bikes in the past with more conventional metal tanks chances are you have a magnetic tank / day bag lurking - I've done a little DIY job so I can make use of mine again 
Get you hands on a pice of mild steel plate approx 1.0mm thick...
Cut to the shape of the base of your magnetic tank/day bag, drill a couple of holes, paint and hey presto you have your base plate ready to fix to the bikes rack......for your new tail bag ;-)
Not sure how I managed such a crap out of focus photo, still rubbish after major downsize :-(
Two fixing holes top and bottom (the other 4 'dots' are little rubber feet) - stainless steel button head Allen bolt, washers to use as a spacer for the frontmost mount and stainless steel self tapper.
The bolt screws into the captive nut at point (1) hence the washers for spacing and the self tapper screws into a small pilot hole (2) drilled in the plastic top box mount.
Here ya go...
I've glued a piece of black vinyl sheet on top to make it neater.
And ready to go (tail bag security strap locates round the middle rack mounting 'post')
Free and takes 2 secs to remove to use the top box - carry the plate in your topbox when travelling to your holiday destination then swap out for day trips ;-)
Get you hands on a pice of mild steel plate approx 1.0mm thick...
Cut to the shape of the base of your magnetic tank/day bag, drill a couple of holes, paint and hey presto you have your base plate ready to fix to the bikes rack......for your new tail bag ;-)
Not sure how I managed such a crap out of focus photo, still rubbish after major downsize :-(
Two fixing holes top and bottom (the other 4 'dots' are little rubber feet
) - stainless steel button head Allen bolt, washers to use as a spacer for the frontmost mount and stainless steel self tapper.
The bolt screws into the captive nut at point (1) hence the washers for spacing and the self tapper screws into a small pilot hole (2) drilled in the plastic top box mount.
Here ya go...
I've glued a piece of black vinyl sheet on top to make it neater.
And ready to go (tail bag security strap locates round the middle rack mounting 'post')
Free and takes 2 secs to remove to use the top box - carry the plate in your topbox when travelling to your holiday destination then swap out for day trips ;-)
