At the minute this is purely hypothetical.

When I say safe I mean lowest chance of failure.

So …..

Remeaning a seat tube by 0.2mm

Or

Taking the same amount off of a seatpost.

Frame is steel and ST is double butted.

Seatpost would be a Thomson.

Keen on thoughts.

Get a post that fits?

You knew that was coming, if the post will go in a late I’d do that. Imagine if it snaps an slots up your bum 😯

Neither.

Out of interest what sizes are the post and frame?

The frame currently has/requires a 27.0 post.

I would in theory like to run a post with some layback I.e. a Thomson (which I have).

Argos are happy to do the reaming but cannot guarantee they could get the reamer deep enough as to fully lower/significantly lower the post.

Not really a problem as I run a lot of the post out of the frame.

Just kicking ideas about

Get another seatpost. FWIW, I wasn’t impressed with the one and only Thomson I had – bent within a few weeks and then started to crack..

Edit >>>> 27.0 & 27.2

Ream the seat tube.

Surely the least hassle / expense / worry would be to get a new seatpost and sell your current one?

How much would it cost to get your frame reamed? How much for a new seatpost? How much could you sell your old one for on the classifieds? What value do you place on your safety?

Not really a problem as I run a lot of the post out of the frame.

Now that definitely sounds like a good reason why reaming the frame wouldn’t be a problem 🙄

Isn’t 27.0 an odd size? Is the frame welded or brazed? If It’s brazed then get a framebuilder to stick a 27.2 seat tube in.

I did that to a USE seatpost, and I’m a biffer, and it didn’t snap.

It depends on the wall thickness of the tube and post.

Ream the post, when it fails it will exact revenge by reaming your arse

Thank you all.

Remember this is hypothetical 😉

The issues emanates from there being a lack of decent 27.0 posts with layback.

26.8mm post with a shim?

Remember that the wall thickness of Thomson posts isn’t uniform. They are 3mm thick at the front and rear but only 1mm thick at the sides.

Ream the frame, because as long as there is sufficient depth so as the minimum insertion goes in, then you can cut the post down to length, I’m assuming you hypothetically know how high you have your seat.

26.8mm post with a shim?

This.

0.2mm shim?

Does going down to a 26.8 post open up the options for a post with layback?

My Thomson wore quickly and ended up pretty slack in the frame… So just stick it in a 27.2 frame for a few months til it’s down to size 😉

ritchey do 26.8 layback posts and so do thomson!

Thomson do 27.0

Yes but they don’t do a 27.0 layback.

Buy a frame that fits?

Are there no 27.0 posts with a decent setback then?

get a smaller post, have a shim made from a bit of alu tube (you could probably do it yourself!).

taking material away would make me nervous.

26.8 layback tommy on chainreaction

ooo looky a 26.8 layback

Have you tried the 27.2 post in the 27.0 frame?

Just asking like, because I did that once. Ran fine for a year or two until I found out it had the wrong post in it.

got a 27.2mm I beam post turned down to 27.0mm for an old kilauea frame, its only 0.1mm off the seatpost

For the sake of .2 mm get a strip of emery and take it off your post. Posts are cheaper than frames do mod the post to suit the frame. Seems crazy to do it the other way round and ending up with a bastardised frame.

Or do the frame and never have to muck about with every seatpost you might potentially use?

If you do the frame you have the same volume of metal as a narrower post in the unreemed frame assuming wall thickness is the same. And if its butted the reemer should be able the get the full length of the butt?

If you reduce the seatpost you have a weaker seatpost which is lovely right at the point it leaves the frame…..

Ofcourse everything is so over designed you probably wont die eitherway….

…….. maybe

Get a custom seatpost.

mines from Matt at 18bikes, He’ll also sort your frame to a better size, seen it done on a few Cove frames.

I’d ream the frame. Then you have a big choice of posts, including a few droppers. Isn’t the layback on a Thomson pretty minimal, though?