Jamis Allegro Sport

[Rhythm Thief]

If you have one of these, it might be worth having a good look at the drive side chainstay. We've had two identical bikes donated to Enviroability and both feature terminal cracks in exactly the same place.

 

[T4tomo]

Maybe the folly of naming a bike model after a crap british leyland car?

 

[Dogtrousers]

Might be worth dropping Jamis a line. They'll probably ignore you though.

 

[wafter]

That's an interesting failure - looks like the result of aluminium's propensity to work-harden in the face of over-zealous application of the squashy-squashy machine at the stay.

Probably "fine" when it left the factory but likely provoked by vertical loading during use since this area will see the highest strain under these conditions.

I assume the crack isn't repeated on the underside of the chainstay..?