Got a 30.9 Reverb and a frame with a 31.6 seat tube. USE do seatpost shims and they get mixed reviews. Has anyone used them on a dropper post? If so, any good?

Yep. Did the same with my 30.9 Reverb. No probs.

Works fine for me

Brewdog Punk IPA beer can shim works fine for me

works fine for me

That’s good to know – thanks all

Depends on the frame as well…should be fine but if you have a huge amount of post showing it might be an issue if the seat clamp bit is detachable from the frame…if the clamp is part of the frame and you haven’t got a huge amount of post showing and the shim is very long then it’ll be fine.

I had one on my C456 for a couple of years with no problems.

i use the exact setup you’re talking about with a USE Shim.
I use carbon assembly compound both inside and outside the shim

As above, no problems at all.

i use the exact setup you’re talking about with a USE Shim.
I use carbon assembly compound both inside and outside the shim

Same here too.

It’s only done two rides so far like that, but so far no issues.

You will die. That is pretty certain. It is unlikely to be the result of using a shim with a reverb, though.

The only issue I could think of is being able to tighten the clamp sufficiently without impairing the action of the post – but I doubt this will be a real issue.

One thing – after letting my reverb seize in the seat tube of my bike 😳 I had to take it to the seatpost man. He reckons copper grease is better than assembly paste as it is less likely to result in a seized post.

Or you could just look after it properly unlike me.

Ran a 31.6 reverb shimmed in a 34.9 frame for a year with no bother at all.

If you do use a Reverb shim, just make sure the shim is a minimum of 10cm and both post and shim are below the weld point juncture of the top-tube and seat tube…too little in this area will put strain on the weld point…could in some cases cause it to fail.

I used one, it worked well but occasionally needed removing, cleaning and putting back in with new assembly paste to prevent it from creaking.

That was using a torque wrench at the correct torque, perhaps if I had tightened it a slightly bit more it wouldn’t have become a problem

Mines a31.9 and has been shimmed to 31.6 in a steel, a carbon and an alu frame. No issues in any of them and that’s with a USE shim.

I did that till I swapped with someone who had the opposite problem. Should still have the USE shim somewhere. Would be postage cost if you wanted it.

Just buy a new body tube and fit it so you have the correct size post. Simple.

A cut up plastic bottle works fine

Thanks all – you’ve reassured me – JPR thanks for the offer but I’ve already ordered the shim (Hurry up CRC!)

@essexbiker what did you order exactly as I need the same and can’t find the right one on CRC