Welding a cracked frame?

[Beaver]

This is a 2012 Rocky mt Element 970, 29er with decent spec'd parts, sram xo shifter/deraileur, Monarch shock, rock shock dropper, don't know the rest but probably decent. If not weldable, a good source of parts.

[SumJongGuy]

Seat post tube?. Could make ridable but.probably only with seat at.fixed height. No more dropper utility.

Did you have the sear post bottom above.the joint.when it failed? That will cause that to happen

[muted]

My local custom frame builder helped me out when I need a fix on an old steel frame from yeti. Pretty easy.

[Beaver]

It's not my bike, it's for sale for $500cad just down the road. It's a small frame so someone too tall probably raised the seat too high. I might go talk to a professional welder.

[jm2e]

Alloy frames can't be repaired. There are roughly 1,000,000 pages on the interwebz about it.

[XXX-er]

that rocky looks like aluminium to me, usually the only way to deal with cracked Aluminum is replace the frame but you got a whole bunch of seat post in the seat tube so its not really as bad as say a head tube

I think there is a guy in Vancover who welds aluminium bikes but if you don't already own this bike i would just give it a pass

[Dantheman]

Could you just run a nice long seat post? 500 canadian pesos seems like it could be worth it for the parts alone, though.

[GeezerSteve]

My local custom frame builder helped me out when I need a fix on an old steel frame from yeti. Pretty easy.

Easy because it was steel. (BTW, not all steel frame repairs are easy.)

Al alloy frame is a different animal. Most Al alloy frame cracks cannot be repaired safely. In the rare case when a repair is possible, the frame must be heat treated to proper spec (at least normalized and/or stress-relieved), which can result in warping and/or stress cracks.

The general rule re repairing Al alloy frame: Don't bother

[XXX-er]

When I broke the seat mast on a Gary Fisher Y bike I took it back to RedShred in Williams lake, Red said that the factory was complaining about how many frames we break up here in Canada eh

Red said the hands down best to deal with was Brodie (we broke one of them as well ) cuz whenever some local kid did something really stupid the guy would say " he did what, really!" laugh and give something even if it was only a crash replacement

Junior could snap square taper spindles almost on command until he got a FS Devinci which he eventualy broke completely in half

[Dee Hubbs]

I’d buy and run it with the longest seat post insertion you can find.

[muted]

Easy because it was steel. (BTW, not all steel frame repairs are easy.)

Al alloy frame is a different animal. Most Al alloy frame cracks cannot be repaired safely. In the rare case when a repair is possible, the frame must be heat treated to proper spec (at least normalized and/or stress-relieved), which can result in warping and/or stress cracks.

The general rule re repairing Al alloy frame: Don't bother

Yeah, now looking closer at that pic and also now knowing it's alloy, I shoulda never posted anything.

[Dee Hubbs]

Our shop had some cheap rental bikes in our fleet that had a bend in the seatpost, not allowing the seat to be dropped low enough on size smalls and X-smalls. We cut some seat posts short to accommodate these bikes. A few super short seat posts ended up on Large frames, and ended up braking a few frames in this same way. A few were salvageable by cutting the seat tube shorter and lowering seat clamp. Some were write offs because the break was too close to the top tube.
Like I said above, if the fit allows it I’d run a deep insertion seat tube, even a dropper in that frame without too much concern.

[grinch]

You might be Able to grind it off at the crack and grind another slit on the backside of the seat tube. Use a dropper post(with max insertion as deehubs suggests). Crack looks close to the top tube weld but it may be possible to shave down and Allen bolt seat clamp to fit. Looking at the pic, a little shave of the clamp and it may slide over the weld.

[LesterSmoove]

So, I almost completely snapped the seat tube very low on a 2013 Marin Mount Vision today. no crash, just riding it. aluminium frame. online research tells me that this is completely unfixable. has an undamaged and almost brand new fox transfer dropper of some kind, which I'll list for sale shortly. considering I'm the second owner and therefore not covered by warranty, I doubt there's a reason to delete the following paragraph and bug marin for a new bike.

noticed that the bolts on two of the suspension pivots right near the crack had worked themselves loose. I guess that might cause enough play to snap the frame? I'm fat too, which can't help.

TGR was my last stop for research on welding aluminium frames before concluding that this is unfixable, so I guess i just wanted to say FUCK.

[XXX-er]

No you say " cool I get to buy a new bike! " its an opportunity

[Laps]

So, I almost completely snapped the seat tube very low on a 2013 Marin Mount Vision today. no crash, just riding it. aluminium frame. online research tells me that this is completely unfixable. has an undamaged and almost brand new fox transfer dropper of some kind, which I'll list for sale shortly. considering I'm the second owner and therefore not covered by warranty, I doubt there's a reason to delete the following paragraph and bug marin for a new bike.

noticed that the bolts on two of the suspension pivots right near the crack had worked themselves loose. I guess that might cause enough play to snap the frame? I'm fat too, which can't help.

TGR was my last stop for research on welding aluminium frames before concluding that this is unfixable, so I guess i just wanted to say FUCK.

What diameter is the transfer? I might be interested.


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[LesterSmoove]

What diameter is the transfer? I might be interested.


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