Cracked head tube

[Cocximus]

My jake the snake head tube cracked. I know I know, the frame is done, but this is 2021 mad max bikes edition. It's very hard to find a bike and prices are ridiculous. I am looking for ways to squeeze a few more months out of it.

Options?
1. Shaft collar?

2. Wrap the head tube in g-flex + fiberglass? Dunno if this would help much with the crack progressing, but I hope it would prevent a sudden catastrophic failure.
3. ...?

[toast2266]

You're gonna want this:



plus this:

[stealurface831]

thought this was about a crackhead in a tube.

[grinch]

Looks like the crack starts to splay at the top of the bottom cup. Don't do it. Im sure someone has something safer laying around

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[rideit]

See my username.

Seriously, I doubt things would end in catastrophic failure before you had a chance to get off of your bike. Does it creak/etc when you ride it now?

[XXX-er]

JB weld ductape WD 40

but seriuosly maybe talk to the mfger

[Cocximus]

Yes the crack splays.

There is no slack or clicking.


Anyone ride the carbon jake frames? Are they worth the price jump?

[milestogo]

Drill tiny holes at the ends of the crack, that can help it from propagating.
Then Fiberglass.
If they can build bikes out of bamboo you should be able to keep it running for a bit.

[Peruvian]

Contact Kona. Then report back.

[grinch]

Kona are generally good with warrantee and crash replacement. That'd be worth a try

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[evdog]

Further point to add - bike co's seem to be holding separate inventory to take care of warranty claims. So even if this doesn't qualify it may be possible you could score a crash replacement from said stock, even if regular stock is out.

[John_B]

See my username.

By that logic we also should be waiting for Ill-Advised-Strategy to make a post too. I vaguely remember him fixing up a seatstay of a scooter with fiberglass tape? A little less sketchy then a cracked headtube.

[mntlion]

any local welders? might be able to do a wrap around the crack that comes back to the downtube?

[rideit]

You would probably have to re-heat treat the frame with a weld like that. I guess my point is that will give you some horrendous feedback before it catastrophically fails, IMO. I wouldn’t go trying to get downhill KOM s, but I would certainly still take it for a spin until it really cracks.

[XXX-er]

Jakes come in Carbon altho its unclear what this is?

depending on if its carbon or not the warranty is different

https://konaworld.com/warranty/

[toast2266]

You would probably have to re-heat treat the frame with a weld like that. I guess my point is that will give you some horrendous feedback before it catastrophically fails, IMO. I wouldn’t go trying to get downhill KOM s, but I would certainly still take it for a spin until it really cracks.

...Maybe?

I've only snapped off one head tube in my time, but it was almost completely without warning. I was lucky that it happened on a very minor bunny hop in a parking lot and it held on by a sliver of metal at the top tube that didn't detach.

If I'd been at full speed on a trail, it would've sucked. A lot.

I've seen steerer tubes rip out the front of a head tube through cracks that look like op's. Maybe he could limp it along for a bit. But if that thing fails, there's a 99% chance that it'll be the worst fucking crash OP has ever taken. Cracked headtubes and cracked handlebars are two things that aren't worth gambling with.

[rideit]

Fair enough.
Burn it with fire, and nuke the remains.

[VTskibum]

No way I'd be riding that more than to a neighbors house. Yeah may not fail catastrophically but if it does that's gonna be a major problem. Have an old steel Salsa Mariachi frame that I retired b/c it has a smaller crack than that in the downtube right on a gusset and this has way more potential for failure.

Contact Kona, if that doesn't work there are still frames to be found right now, even if it's a hold-over frame.

[bagtagley]

But if that thing fails, there's a 99% chance that it'll be the worst fucking crash OP has ever taken. Cracked headtubes and cracked handlebars are two things that aren't worth gambling with.

I’m surprised the discussion made it beyond this. I wouldn’t ride that thing down the block.

[Cocximus]

It's 7005 aluminum, apparently no need to heat treat it. Any recs for a van area welder?

Kona only open thursday to friday. I will drop by, but the frame is 2012.

Looking at youtube it seems I misinterpreted "CX". I thought CX meant 90s rigid MTB with drop bars on green trails.

[Cocximus]

Anyone try the knolly cache steel? Looks like an amazing bike especially for doing what I should not have been doingwith the JTS. But, how is it on the road? I hang with some pretty fast road bikes and the JTS was no slough.

[jono]

It's 7005 aluminum, apparently no need to heat treat it. Any recs for a van area welder?

7005 was typically heat treated to a t5 condition, which is much easier in production than t6, but that's still heat treatment, despite how the final step was often combined with powder coating (which lead to a lot of over-simplified descriptions in bike press). The material properties compared to as-welded are pretty different, though, like almost 5x the yield strength. I would not go this route.

[snowaddict91]

Its a nine year old bike that it sounds like you've rode hard. Its new bike time.

[toast2266]

It's 7005 aluminum, apparently no need to heat treat it. Any recs for a van area welder?

7005 doesn't need a complicated heat treating process, but it still needs to go through a couple stages in an oven at various temps. The temps are relatively low, so that makes it easier. But it's still probably gonna ruin the paint on the rest of the bike.

(Edit: Jono beat me with actual info)

[XXX-er]

Its a nine year old bike that it sounds like you've rode hard. Its new bike time.

this ^^ if OP has good components maybe they will go on another used frame

Vangroovy should be a great place to pick up a used frame,

if you talk nice to Kona maybe they help you out for cheap $

but trying to weld aluminium could do all kinds of shit to a compromised pretty important joint

I wouldn't fix it