Interesting coming back to this thread and not seeing any sort of resolution to it. There don’t appear to have been any further failures, could this be due to riders stopping using I-Beam posts? I have a particular interest in that I have three bikes fitted with I-Beam posts and saddles, the oldest six years old, the newest pair around a year old. The thing that strikes me is that the failures seem to affect the newer micro posts, which have the head bonded into a tube. Mine is all one piece, so there is no joint to fail. Could the problem lie in the fact that the saddle is so much more rigid fore-and-aft, which may place a greater strain on the joint, especially in very cold conditions. I’m no engineer, but there’s a sense to it; conventional saddles have a fair bit of flex, which would take the strain away from that joint. Pure speculation on my part, but it adds up to me, and I’m not stopping using mine.

CountZero of the two failures, which occurred to me one, was on a 12 month old ‘old’ style post and the other on a 4 ride old ‘New’ micro post…

Common denominator for these failures and for one the other failures posted here was that they were 27.2 dia and had been ridden in cold weather failures seem to occur to the rear of the post where the head is bonded into place

As for the question of usage or stress one broke on Weavern Lane nr Chippenham and the other on the Canal path to Laycock

Despite getting a refund under warrantee for the 2nd post, I’ve not seen any one get an explanation from the importer or manufacturer

I really liked the I Beam system but, after having a 2nd one fail after 4 rides on nothing better than canal paths, I have extreme doubts about the durability of the head & post junction and if anyone is using these posts be alert for creaking noises as these proceeded both catastrophic failures

Hmmmm…..plastic seatposts….

Just fell victim to an SDG I-Beam failure. Reading this thread it looks and sounds like an identical failure to that described in this thread.

The post/saddle was fitted to my Intense Tracer and I was only riding the Marin trail in N Wales, Hardly extreme!

Still waiting for a decision from Silverfish on the warranty claim.

Will update the thread as soon as I have an answer.

Just had a close call – thanks to Martinxyz for spotting it! That’s a crack running down from the top of my seatpost.

I’ve been using SDG I-beams on all my bikes for quite a time now and never had a problem. Built this bike up for road use last week and it’s done all of 120 miles on the road. One factor is that the saddle is about 10-15mm forward of the position it would be in normally while I wait for a shorter stem, so the leverage is higher.

Although the seatpost has been used on my cruiser earlier, it has never seen arduous use.

I’m not greatly upset, but very concerned at the potential damage that could have been inflicted when that crack propagated and the post failed.

The I-beam seatpost on my rigid 29er which has seen several 24 hour races looks perfectly ok, but now I’ll have to worry about that too.

Edit: another I-beam thread