Been given a trailer bike. Nice gesture but the plastic shim that was with it is way too small to fit on my seat posts.
Its an “argos special” so none of the shops seem to carry replacements. Anyone know if these Are pretty generic?

Any experiences of similar issues?

Cut up an aluminium beer can – instant shim material.

and if that’s too thin can you find a bit of hosepipe, use a strip of inner tube, or a bar grip etc.

I’ve adapted 32mm waste pipe/fittings on a Trail-a-bike

So am i correct in thinking that the clamp ought to be tight enough on the post to not slip down to the top of the seat post clamp?

There is a universal joint which would suggest that this is the case. The doubts were sown when I hired one from a trail centre shop, lets call it “Pink Hill” and it was fitted by them just sitting almost loosely on top of the seat post clamp.

It is only for very short term use. The littlest Darling, whilst able to pedal perfectly well, can not be trusted within 100 yards of any kind of other trail users, innocent passers by or immovable objects.

If the clamp can move, the whole setup wobbles, which is horrid for bike and trailer, and if you get metal to metal movement that’s just death on a stick when the seatpost goes. I used a cheap burly post and a spare saddle and left the clamp permanently on, keeping my lighter Easton post and saddle for riding solo, basically as I had them anyway, but it was quicker to swap posts than unhitch the fitting.

Length of innertube on ours. And on a spare post. Not shagging up a Thomson with the contraption.

Cheers chaps. Old seat and clamped solid it is….