[Closed] Cracked Calibre Dune Frame

Yes, in that order.

Op, rake up the old Dune thread as I think there was lots of info on this (known) issue...

I though the Dune issues were due to chain suck cracking on of the stays, not the seat tube…?

Yeah, dune cracks are mostly reported on the chainstay. How much post you got out?...or in maybe?

I'd talk to calibre and Go outdoors. They were excellent with me when I lost my maxle recently, sending me one free.

🤬🤬! So, Go Outdoors are claiming that as I'm running a slightly longer after market seatpost, it's not a warranty case. I replaced the original 350mm seatpost with a 400mm one, which was set to give me another 40mm of height; so it wasn't at full extension.

🤬 fuming.

I'm not a chancing 🤬, so I took the bike in as I'd been running it. By the sounds of things, I should've put the original seatpost back in and tried to con them that that's what I'd been running.

How much post in the frame?

I'm confused I thought you meant your warranty had ended 10 days ago ?

Speak to Dune or another GO store, that is a pile of crock.

How much post in the frame?

This is the question.

Warranty was probably voided the minute you changed anything from the original spec and outside of their prescribed tolerances & fitments anyway

Would the original 350mm post adjust to your ride height, or would it have been 40mm over the min insert?

In fairness, they will have fatigue tested it with the original post. Even at the same length / bending moment / frame insert length, a different post could be flexier or stiffer which changes the stress on that top stub of tube.

To be fair, using a longer seat post may have caused it.

Edit - what Mick said.

Turns out I bought the bike on the 25th of April last year, so it's getting on for a month out of warranty. I appreciate that switching the seatpost for a longer one, is most likely the reason for the failure.Here's some photos of the replacement and original seatpost.

The photos are a bit sqiff, but it was in by about 13cm:

Whereas the original was in by about 10.5cm:

You can see the difference between the two here:

Would the original 350mm post adjust to your ride height, or would it have been 40mm over the min insert?

It would have been 40mm over the min insert.

I'll be emailing Go Outdoors back and contacting Calibre directly. But I guess I'm going to have to suck it up, so time to start looking for a reasonably priced gravel bike.

Your best bet is to contact Mike Sanderson at Calibre.
Very helpful and he sent me a free of charge replacement frame when my second hand frame suffered the chain stay crack.

Edit - here you are:
Mike.sanderson@gooutdoors.co.uk

Make sure you let us know what Calibre say/do..... be interesting how a more value-focused (cough) company handle this kind of thing - they would be entitled to adopt the same position as go-outdoors, but just because they can doesn't mean they should/will.

I seem to remember a very similar thread related to a commencal hardtail - frame had cracked, and they were disputing whether seat post insertion past the top tube junction/brace.

For a given rider that needs a certain seat height, the op's longer post over the original shorter post is favourable Shirley? It has more insertion and so goes further past the junction for the same leverage outside the frame.

Seems weird for that to be the issue Go-out reports.

I'm a bit lost, it's out of warranty so it doesn't matter how it broke it no longer has a warranty. Stuff happens

This. Not sure why Go Outdoors have given you any reason for refusal apart from the obvious.

Having said that, it would be useful to future customers if Calibre or GO would clarify whether swapping a seatpost (or any other part of the original spec) are grounds for refusal.

I suppose I'm mostly pissed off at the, perceived, brush off. If I'd been a deceitful 🤬 and taken it in with the original seatpost, would they have treated it any differently…? My reading of the email suggests they would've.

Here's a shot showing how far into the frame the seatpost actually was:

I ran a Spesh Hard Rock for years, with a longer seat post, that had less tube in the frame and it was fine. I find it hard to accept that the replacement seatpost is the full cause. 🤷‍♂️

For a given rider that needs a certain seat height, the op’s longer post over the original shorter post is favourable Shirley? 

I agree with this, in your case switching to a longet post should have made it less likely to crack than using the original. But its out of warranty anyway so unless you get a "good will" gesture you'll have to suck it up.