Oh Snap, There Goes My Seat Post Clamp…

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Sheered Seat Post Bolt
Sheered Seat Post Bolt

About 25 miles into a 33 mile cycle ride I was just starting a climb when I heard a nasty snap and suddenly the back of my bike seemed very wobbly. Instinctively I sprung to my feet and it was then I heard a nasty bump-clank-clank as parts formerly connected to the bike hit the floor. Turns out that bolt that holds the saddle to the seat post had sheared.

Seat-less bike!
Seat-less bike!

So I rode the remaining 8 miles without a seat which was actually quite fun.

What surprised me though was how difficult it is to get a replacement. It’s a 45mm M6 socket cap (Allen) bolt which are ten-a-penny but if you don’t want to buy them by the kilo they’re quite hard to come by.

So I’ll be going out on a mission to find later and if I can’t I may have to order a titanium one from The Internet. I may not look too hard, there’s no such thing as too much titanium on a mountain bike (unless it’s getting in the way of the carbon fibre, or course).

Addendum Aug 13th

It’s lucky I did do an initial search before ordering a titanium one! I popped to Pedal Power Cycles, mainly because it’s closer than any decent hardware supplier. Turns out it’s not M6. So after some measuring I think it’s 1/4″ UNF – I’ve ordered a pair of stainless steel ones from Ebay for next-to-nothing so we’ll see!

1/4" UNF?
1/4″ UNF?

Addendum Aug 15th

Gah! It’s not 1/4″ UNF either. It’s close, it’s really, really close. It’s possibly close enough to work but it’s not close enough for me to have any confidence in it.

So it’s not a common standard size. I could keep looking but I’m going to end up spending more than the cost of new seat-post if keep getting nearly-but-not-quite right bolts. It could be one of any number of little used standards or even a custom thread just for that seat post.

So it might be better to get a new seat post after all. Think I can justify this one? It is titanium and titanium is good!