Sheared Seatpost

Riding along and hit a small bump in the road. Luckily my balls escaped any damage from the sheared seatpost. One advantage of keeping a short seatpost :-) Rolls slightly scuffed :-(

The seatpost and frame is from my 26 year old peugeot, past 5 years in fixed mode, so its done its time.
This happened about 3 miles from my destination, and boy was it hard trying to ride fixed without a saddle. A serious workout for the calves, and strange looks from other peds/cyclists/drivers. They must think its the latest rage.

On the hunt for another french sized seatpost, or will have to settle for a coke can shimmy job.

From that picture it looks like you've had the clamp on the seatpost upside down...

And never mind short seatpost - looks like you're running the saddle on the top tube!

What diameter post you looking for? I'll keep my eyes peeled whilst trawling ebay.

Seatpost was definitely right way round, as its the only way it could be adjusted in situ from rear. Seatpost had enough clearance for the rear light clamp, so it wasnt sitting directly on the frame.
Not riding 13 miles without a saddle on a fixed tonight. So will drive in tomorrow to pickup bike, extract seatpost and measure. I'll take a look on eBay, cheers.

25.4mm aren't they? i vaguelly remember finding a cheap and cheerful "push" one in cycle surgery on pentonville road. it's about three feet long though.

Borrowed some allen keys and took out the seatpost. Rough measurement with a ruler shows just under 24mm diameter. Had a look on Sheldons site, and the nearest is 23.4mm (hard to find). WIll measure with micrometer tonight.

My options are:

1. bolt on a cheap seat clamp bolt to the hacked original post. Likely to require constant readjustment, and bulky.
   
2. Shim a 22.2mm BMX seatpost to 23.4 with a can shim
   
3. File/lathe down a 25.4mm seatpost to 23.4mm? Filing of 2mm sounds very dodgy, so will avoid this option.
   
4. Find another Peugeot seatpost with integrated clamp (hens teeth?). Anyone have one spare?
   
   

Suggestions welcome.

French proprietary pugs are 24mm and the answer us Decathlon and shim

http://www.decathlon.co.uk/EN/l330-basic-diam-23-4-25-27-2-35412401/

PM Hilary Stone, he may have something lying about

Do you have a better picture of the fracture surface? Interested to see how long it's been cracking for...

Cheers Wicksie, Decathlon have them in stock. Shame their online service isnt quite running yet, will pickup from instore this week.

Samuel, I will post a closeup shot of both surfaces with a proper camera rather than my phone. It looks like the crack was slightly oxidised from the front of the seat tube after which the rest is a fresh shear.

PS It was a 24mm seatpost.

Yeah looks like a small area of fatigue, but no more than 1/6 of the total cross section width. Aluminium's a sneaky customer, you never get something for nothing :-( . Just makes you wonder about all those aircraft flying around with quietly growing fatigue cracks. Or maybe we don't want to think about that...

is that a bubble on the right piece? or is that just the end of the filled piece? if that makes sense

Top of the hollow section (I hope). That would be a pretty horrible casting void if not!

innit. I'm gonna start ultrasounding my seatposts

Yeah looks like a small area of fatigue, but no more than 1/6 of the total cross section width. Aluminium's a sneaky customer, you never get something for nothing :-( . Just makes you wonder about all those aircraft flying around with quietly growing fatigue cracks. Or maybe we don't want to think about that...

Believe me, they check aircraft components for fatigue cracks fastidiously.