I suspect that he would want you riding his bikes and using the gear because they will continue to "trek" even when he cannot. He'll be there, with you, in spirit, with every stroke of the pedal. Then, you can talk about it together.

I saw a movie starring Martin Sheen. He walked a pilgrimage that his son began and died in an accident along the way. He carried his son's ashes and scattered them along the way and then dumped the remainder in the sea at the end. It was a great money.

Your brother will not have died, but, his journey ended in another sense. You can ride for him.