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Frame crack


Lach's picture

By Lach - Posted on 18 August 2013

Interested in any views / recommendations on the safety / feasibility / cost of repairing a badly cracked aluminium frame (see pic). And yes, I should have been using a longer seat post.... Sad

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Zoom's picture

What brand, model is it? So others can avoid the same fate.

Magnum9's picture

Could probably be repaired. If you have the seatpost long enough there wouldn't be a huge amount of load there. I reckon it would be a couple of hundred bucks to fix.

hawkeye's picture

Take it to Stan at BA for an opinion. With a long enough seat post it should be fine. Additional reinforcement like a carbon wrap may be needed. Which bike?

mxracer92's picture

carbon wrap ?? its an alloy bike by looks of it ..

how far was your seat post in .. surely if 70-100mm min insertion this wouldnt of happened

Fatboy's picture

I've done similar in the past. Needs a specialist welder. The ones who work on aircraft are best as light weight aluminium needs a lot of care. You'll end up with some sort of sleeve. It won't look pretty but will save you from throwing it away.

Lach's picture

It's a Bianchi Jab 7500 - but I don't think it is so much a problem with the bike as my stupidity in not getting a longer seat post for it.

craked's picture

mxracer,Lach has already stated that his seat post insertion was incorrect !

Lach's picture

..yeah its aluminium and you have spotted the problem. Was running about 70mm inserted, but about 30mm less than the recommended minimum on the post. Mind you, I've done similar with all my bikes over the years, but pushed my luck a bit too far with this one. The seat post looks fine by the way....

Slowpup's picture

should be able to effect a 'repair' if you just want it rideable again. Like fatboy said, it won't be pretty but it'll be functional.

For the sake of being nosey.... how much post was hanging out and how long did it take to fail? Hardtail or dually?

fairy1's picture

Seat stays welded to the seat tube, guessing a dually Eye-wink

trails4us's picture

Seat stays welded to the seat tube, Guessing it's a hardtail

muvro's picture

Yeah, easy fix and fairly straight forward, but would need a gusset for strengthening. I've done a few of them recently.

Little-Ditty's picture

Gripsport in Melbourne. They are the only choice really. But highly reputable.

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