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Unanswered uhm, is this a crack in my frame? I'm hoping it's just the paint...

EnjOy!

New Member
Jul 8, 2019
31
29
Belgium
I was just cleaning my bike while I noticed this, I hope it's just a crack in the paint..

1.jpg
2.jpg
3.jpg
 

Paul Mac

E*POWAH Elite World Champion
Patreon
Subscriber
Jul 9, 2018
986
1,041
Uk
Doesn't look Like a crack to me.
Its too short and wide, looks to me Like a bit of debris has got in that gap and dug into the paint.
 

EnjOy!

New Member
Jul 8, 2019
31
29
Belgium
Looks pretty wide, can you get a fingernail or tip of a toothpick in there to confirm if it has depth?

I just tried to stick the thinnest needle I have in there, and seems to go in for 3-4mm :censored:
And there also seems to come a little water out of the crack after washing it as you can see on the bottom.
needle.jpg

And here's a video of the needle going in, sorry for my shaky hands
 

Pukmeister

Active member
Jul 18, 2019
283
263
Fareham
Hard to tell without inspecting if it is a crack, a surface flaw or a paint finish defect. I would ask at your supplying dealer. If it is a crack the frame needs replacing or repairing (probably cheaper/easier for them just to exchange the whole bike once labour is charged).

An Engineer will tell you that a crack will propagate under stress as the forces at the absolute tip of the crack are infinite (due to having no radius). You can stress relieve by drilling a hole at the absolute tip of a crack(to create a radius), a silly idea on a bike.

If it is a crack it will only get worse, get it checked. Most frames are guaranteed for the life of the bike.
 

khorn

E*POWAH Elite World Champion
Patreon
Jul 19, 2018
980
1,054
Denmark
I just tried to stick the thinnest needle I have in there, and seems to go in for 3-4mm :censored:
And there also seems to come a little water out of the crack after washing it as you can see on the bottom.
View attachment 17754
And here's a video of the needle going in, sorry for my shaky hands
Based on your video it is for sure a crack and back to the LBS, you will need a new frame if still on warranty. If not ,a good welder can fix it for you but it will hurt the paint.

Karsten
 

squeegee

Well-known member
Aug 19, 2019
360
267
USA
The only way to know for sure is remove the swing arm and strip back a small area of paint in that area, my guess is it's a crack forming that will get progressively worse. Maybe a shoddy weld, too much heat used perhaps causing a weakness on that bearing tube.
 

Mikerb

E*POWAH Elite World Champion
May 16, 2019
6,105
4,636
Weymouth
The area where the "crack is located is not part of the seat tube. It looks to me to be the weld holding the pivot tube to the seat tube, which has been machined back. The defect is therefore likely to be a defect/foreign matter in that weld. That face also has some defects not machined smooth at 12 oclock. If I was being super critical I also do not like the look of the weld joining the pivot tube to the bottom of the seat tube either. The weld has undercut the ally of the seat tube ( see your second photo).
 

Pukmeister

Active member
Jul 18, 2019
283
263
Fareham
If the weld has inclusions in that area or porosity, what about the rest of the bike especially the bits you can't see? It doesn't say much for the welding processes or quality control checks during manufacture.

I would be concerned about frame strength/integrity.
 

Rusty

E*POWAH BOSS
Jul 17, 2019
1,513
1,673
New Zealand
This is a perfect illustration why one should regularly perform a close inspection of your frame. Nothing worse than not noticing something then having it fail and cause injury.
 

njn

Active member
Founding Member
Mar 14, 2018
340
178
USA
definitly looks like a not so perfect weld that was machined. paint is intact around the flaw, so it's not flexing and the weld is strong.
 

EnjOy!

New Member
Jul 8, 2019
31
29
Belgium
Thanks for the replies everyone, this morning I sent an email to bike24 with the pictures. Just waiting for a reply now, but they are always a bit slow on replying email
 

EnjOy!

New Member
Jul 8, 2019
31
29
Belgium
Bike24 told me I'm going to get a new frame, just finished packing my bike so I can send it back.

Was hard to find a box that fits my bike but found these big boxes at work and was able to modify them.

From this (x2)
IMG_20190909_1512590.jpg

To this
IMG_20190909_1609309.jpg


Now I have to ride my stupid city bike again :(
 

Mad Mark

E*POWAH Elite
Patreon
Nov 2, 2018
434
670
Burton on Trent
Bike24 told me I'm going to get a new frame, just finished packing my bike so I can send it back.

Was hard to find a box that fits my bike but found these big boxes at work and was able to modify them.

From this (x2)
View attachment 18311
To this
View attachment 18312

Now I have to ride my stupid city bike again :(
My misses has got an old box, do you think you could do anything with that ?
 

EnjOy!

New Member
Jul 8, 2019
31
29
Belgium
Time for another update

My bike arrived at bike24 and Cube sent them a new frame... which also had these weird openings
P1080290.JPG


They mailed back to Cube and they didn't seem to have any more of these frames.
But they also told me "Cube confirmed that there will be no stability issues ".
I had the option to take this frame or get a refund, I told them i'd rather have a refund if these openings are not supposed to be in the frame.

Didn't think I would have to look for a new bike this fast, too bad I can't find one that I like as much as this one in the same price range :/
 

Rusty

E*POWAH BOSS
Jul 17, 2019
1,513
1,673
New Zealand
That is just real bad quality control.
If the welding is not correct looking at that, then how can one be sure the rest of the weld has the correct penetration. Not much of a chance I would buy a Cube looking at that.
 

HORSPWR

E*POWAH Master
May 23, 2019
849
675
Alice Springs, Australia
There is no way that will fail, there is heaps of weld underneath and on top, I would even suggest that there never was any weld in that area where the gap is above, there simply isn’t any need for weld in there. To put weld in that area is overkill.
 

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