As a Mechanic, in a LBS, we have no trouble dealing with Racks and mudguards
on Bikes with disc brakes..
(@ the shop, here, buying the rack can include installation..)

I have a few small wheel bikes, their front rack is an over the wheel ..

and quite low.. ..

my 2 panniers have D rings on them , so I can hook on a stretch net ,
across both, to bring home Pizzas..

Being in Front, bag is handy to access.. my rain cape is in one,
to pull out and put on in a moment..



But when I go for groceries I use the trekking bike with both racks. rear bags are bigger.. rarely buy more that will fit in the 2..







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