LMX BIKE in distress: crack on the main frame

[enduromac]

https://imgur.com/KF5GmNH
In my beloved LMX 81 is present this crack, I know here are some rally smart and full of experience people so I ask if you have some suggestion that IS NOT that simple say : dump that frame! It's comdemned! I want you to notice that the welding starts different right in correspondence of the crack, so one can think the crack was there from the very birth of the frame. Please help. Thanks

 

[HK12K]

Find someone who is proficient in welding aluminum and have them grind out the failed weld and re-do it. You're right that weld didn't look good to begin with, especially considering the price. Might even contact LMX and see if they'll do anything for you, used as it may be. That kind of failure looks an awful lot like a manufacturer defect to me.

 

[enduromac]

Thanks HK12K for the reply. I had already brought the bike to an expert welder who has already made a special for me (Beta 300 engine in CRF 250 frame). Bike was already there, because the rear swingarm has broken and turn out also has other cracks (see photo). As for LMX, I asked and I am waiting for an answer. Hoping. On another occasion they behaved correctly.
https://imgur.com/vnQMKup
https://imgur.com/EGBr6M5
https://imgur.com/BkoNsBz
https://imgur.com/KRo6YEY

 

[enduromac]

additional informations: I am 62 years old and weigh 76 kg and I do not jump with the bike Sometimes the front wheel is not on the ground and not more

 

[HK12K]

Oh my, that thing is literally crumbling from underneath you. I hope LMX steps up and does something to make it right.

 

[st35326]

Gross. I'd part ways with that frame ASAP.

 

[HK12K]

Please do let us know how LMX responds to this. It is of great interest.

 

[enduromac]

If possible I would like to stay on the point of the crack on the main frame: the swingarm is a piece that seems to be replaceable with the one, HOPEFULLY, better designed, from the LMX 64.
The fact that the break along the weld can always be present and I have not noticed, would it also give a chance to the hope of being able to continue using the bike, without aggravating the problem (after replacing or repairing the swingarm)?
On the other hand, it could be assumed that the frame is starting to break there, as it does not support the effort that tends to open it, on the part of the seatpost, as I use a fairly long off-seat and therefore I do not keep the saddle downhill, as I like to apply myself seriously on the pedals. How about? Hoping to have explained myself
Thus the first opinion (manufacturing defect) would, paradoxically, give tranquility.
The second one (design defect) would give the certainty of not being able to use the bike, without putting a hand on a reinforcement.
Thanks again

 

[HK12K]

Honestly I would have a difficult time ever trusting that frame again. The idea of it coming apart while at speed would always be nagging at me.

That said if you can replace the swingarm then have your trusted metalworker fix the remaining broken weld and review the rest to ensure he doesn't see anything else there may be hope.

Not that I've any direct experience with it but apparently they can x-ray the frame which can reveal hidden defects as well, which frankly you may want to lead with as there could easily be more failure prone welds on that bike based on what I'm seeing.

Good luck and best wishes on getting back in the saddle again soon.

 

[enduromac]

for those who may have been interested, the discussion has had developments here
https://endless-sphere.com/forums/viewtopic.php?f=3&t=100198&p=1549985#p1549985
Including an answer from Adam of LMX