Bongo Fury

noticed this morning that when i'm traveling slowly (around 10mph) the bongo seemed as if it was going over very small speed bumps.
it felt like the rear drivers side was dipping down, if i went a bit faster bumping sped up, slower = slower so i'm assuming its something to do with one of the wheels?
i was pretty tired but i don't think i imagined it. anyone experienced anything like this?

Are they the original tyres meek?

Perhaps one had been left flat at some stage, and now that a bit more wear has set in, its manifesting itself as a flat spot?

A tyre that has locked up can flat spot too.

Sometimes a tyre can still be within its legal limit,but the sidewall starts to let go,this will give the bumpy effect you are experiencing.

If you have aftermarket alloys fitted,perhaps a centre spigot ring has broken,is missing,or something similar.

It may be worth rotating all the wheels, as this can often cure such problems.

Take your van to a tyre depot and ask them to put it on a wheel balancing machine and turn it slowly by hand to check for any low spots - I once had a brand new car with steering wobble and they found both front tyres had a low spot using this method.