stefmeister Posted September 22, 2021 Share 15 hours ago, Mojoman said: Raise your hand if you said this would happen again...Less than 150km...Now the talk is I didnt have the seatpost in deep enough.,... Momsen can kiss my behind! POS bike...???? Forged in the Untamed South Africa - And broken in the Magaliesberg..... Wow, same repair job has the same crack and they have the cheek to call you out on the seat post. Real class and great backup service...NOT. Never liked the brand. And who on earth thought Mompsen is a cool name? justinafrika and Mojoman 2 Link to comment Share on other sites More sharing options...
Jewbacca Posted September 22, 2021 Share 7 minutes ago, stefmeister said: Wow, same repair job has the same crack and they have the cheek to call you out on the seat post. Real class and great backup service...NOT. Never liked the brand. And who on earth thought Mompsen is a cool name? Isn't it his surname? ???? Mojoman, Mountain Bru, NickGM and 2 others 5 Link to comment Share on other sites More sharing options...
Mojoman Posted September 22, 2021 Share And thats why I WILL NOT take another Momsen frame, the level of service from TWT is absolutely shocking and utterly pathetic, They took a whole week with no comms on what they were planning on doing..I was going to take the STF frame but today opted against it as I may have other options...so I asked if I can get my refund ASAP so I can move forward...Now they wont pay until the broken frame has been collected...FFS It seems the customer must just suck it up...Good luck if you own a Momsen.... I think its a sign to sell all this cycing crap and get into my new hobby of shooting things!???? Hopefully cheaper and less things to break... Edited September 22, 2021 by Mojoman Link to comment Share on other sites More sharing options...
Mojoman Posted September 22, 2021 Share 2 hours ago, stefmeister said: Wow, same repair job has the same crack and they have the cheek to call you out on the seat post. Real class and great backup service...NOT. Never liked the brand. And who on earth thought Mompsen is a cool name? Sadly I quite enjoyed my 4 years on that AL129... If it wasnt for the dismal service I would have continued... I just dont need this headache and battle being repeated when the next frame breaks... Link to comment Share on other sites More sharing options...
i24 Posted September 22, 2021 Share 19 hours ago, Mojoman said: Raise your hand if you said this would happen again...Less than 150km...Now the talk is I didnt have the seatpost in deep enough.,... Momsen can kiss my behind! POS bike...???? Forged in the Untamed South Africa - And broken in the Magaliesberg..... Was this repair done under manufacturer's warranty, or was it an "approved" repair by one of their dealers? if so Momsem have some explaining to do. Welding aluminum is a science. Depending on the grade of aluminum specific pre and post weld heat treatment is essential. From the post repair, pre-repaint photo's it was clear this weld got neither. That is one of the most highly stressed areas of the frame, if it had cracked once there is no way this repair would not fail again. This was just a "cover up" job. The only motivation I can think of doing a repair like this is to enable the bike to be sold to some unsuspecting buyer - which the OP clearly had no intention of doing. This is an interesting story on how Giant make frames https://www.cyclingnews.com/features/tech-inside-giants-taiwan-bike-factory-part-three/ "Once welding is completed, frames are sent off for the first round of heat treatment (to T4 spec, for those that are interested), checked again for alignment, then sent for the final round of heat treatment (T6 spec)." ChrisF 1 Link to comment Share on other sites More sharing options...
Mojoman Posted September 22, 2021 Share 31 minutes ago, i24 said: Was this repair done under manufacturer's warranty, or was it an "approved" repair by one of their dealers? if so Momsem have some explaining to do. Welding aluminum is a science. Depending on the grade of aluminum specific pre and post weld heat treatment is essential. From the post repair, pre-repaint photo's it was clear this weld got neither. That is one of the most highly stressed areas of the frame, if it had cracked once there is no way this repair would not fail again. This was just a "cover up" job. The only motivation I can think of doing a repair like this is to enable the bike to be sold to some unsuspecting buyer - which the OP clearly had no intention of doing. This is an interesting story on how Giant make frames https://www.cyclingnews.com/features/tech-inside-giants-taiwan-bike-factory-part-three/ "Once welding is completed, frames are sent off for the first round of heat treatment (to T4 spec, for those that are interested), checked again for alignment, then sent for the final round of heat treatment (T6 spec)." My choices were: 1. Repair 2. Take a payout 3. Cough up more money and take the steel frame and cough up even more money again to get it rideable (new rear wheel etc) I havent had full time work for quite some time so I opted for the repair to save some money...Lol..my mistake.... I did actually speak to the welder who performed this fix and he sounded as though he knew what was going on as I had also spoken to a metalurgist mate and the guys I worked with at a tool and die factory so I had an idea of what to ask... Whether or not the area was correctly treated pre and post welding is another story though..No-one will ever know for sure......But they have you up against a wall really and they know that hence the poor scenario thats played out here....I was offered R2500 payout on the frame...R2k on the frame and R500 for the assembly...No worries about what the cost would have been if I wasnt able to strip the bike down and reassemble myself.... I have now opted to take the payout, I was going to take a steel frame and just sell it on but bugger that. Then its another problem for another poor soul! TWT couldnt even tell me if there were spare hangers for the replacement frame as well.... Lol..Fanks but no fanks mate... Anyway...lesson learnt...Some of it was my fault anyway...Make sure you have the right insurance to cover you in a case like this... Edited September 22, 2021 by Mojoman Link to comment Share on other sites More sharing options...
GhostSixFour Posted September 22, 2021 Share Didn't you say Outsurance was willing to insure after the repair? Did you not get it insured after the first crack and everyone told you it would crack again? Mojoman 1 Link to comment Share on other sites More sharing options...
GhostSixFour Posted September 22, 2021 Share On 8/12/2021 at 1:14 PM, Mojoman said: I did speak to their welder...seems like he knows his stuff....Nothing I can really do now anyway....no money for a new bike so over the barrel, vaseline free, I can like to be.... Unfortunately Momsen made no offer of any steel frames....quite honestly though I think my time with this brand is done after speaking to a few people including bike shops. 4 Years ago when I first got the frame and the clear coat was coming off they didnt want to replace the frame...I had to dance and invoke the CPA to say I then wanted a full refund...then I got another frame... Seems its one of those when you have paid then bad luck things..... Lol...after talking to Outsurance it seems they can insure it after being repaired... Yeah, this. Did you not get it insured? Link to comment Share on other sites More sharing options...
Mojoman Posted September 22, 2021 Share 7 minutes ago, GhostSixFour said: Yeah, this. Did you not get it insured? I did but the inception date was too late. ???? So if you do own a AL129 then make sure you have cover...according to TWT there are no frames so there will be no replacement for you. Edited September 22, 2021 by Mojoman GhostSixFour 1 Link to comment Share on other sites More sharing options...
Trashy Posted September 22, 2021 Share 32 minutes ago, Mojoman said: Whether or not the area was correctly treated pre and post welding is another story though..No-one will ever know for sure...... You most certainly can know for sure if it was heat treated. Heat treating to T4 is around 400°C for 40 minutes if I remember correctly. At that temperature the paint burns right off the frame... It is therefore very clear that this was not done for your repair. The problem with many aluminium welders that do these repairs, is that they seldom deal with aircraft grade alu that bike frames are made of. When we used to repair frames it wasn't uncommon for people to come with prior welding done on the frame. In addition. Even the slightest impurity in that weld (old paint, dirt) would compromise the weld strength. Cleaning the area for repair is not a quick and easy process. Mojoman, Mountain Bru and ChrisF 3 Link to comment Share on other sites More sharing options...
Trashy Posted September 22, 2021 Share 19 minutes ago, Mojoman said: I did but the inception date was too late. ???? So if you do own a AL129 then make sure you have cover...according to TWT there are no frames so there will be no replacement for you. It's likely that your frame was just a dud. That is one of the hardest welds to get perfect and if the seat tube had been over-enthusiastically sanded before assembly, it may just have been ever so slightly too thin. Mojoman 1 Link to comment Share on other sites More sharing options...
i24 Posted September 22, 2021 Share 19 minutes ago, Mojoman said: My choices were: 1. Repair 2. Take a payout 3. Cough up more money and take the steel frame and cough up even more money again to get it rideable (new rear wheel etc) I havent had full time work for quite some time so I opted for the repair to save some money...Lol..my mistake.... I did actually speak to the welder who performed this fix and he sounded as though he knew what was going on as I had also spoken to a metalurgist mate and the guys I worked with at a tool and die factory so I had an idea of what to ask... Whether or not the area was correctly treated pre and post welding is another story though..No-one will ever know for sure......But they have you up against a wall really and they know that hence the poor scenario thats played out here....I was offered R2500 payout on the frame...R2k on the frame and R500 for the assembly...No worries about what the cost would have been if I wasnt able to strip the bike down and reassemble myself.... I have now opted to take the payout, I was going to take a steel frame and just sell it on but bugger that. Then its another problem for another poor soul! TWT couldnt even tell me if there were spare hangers for the replacement frame as well.... Lol..Fanks but no fanks mate... Anyway...lesson learnt...Some of it was my fault anyway...Make sure you have the right insurance to cover you in a case like this... I am very surprised that a responsible manufacturer would have offered "1. Repair". This was never a viable option. It's only purpose that I can see is to deceive a future owner. A typical Aluminium bike frame is made from "6061" or similar tubing. After welding it gets "placed in an oven at 530C for 40 min" then quenched to room temperature (eg in a water bath or spray). Then optionally, re-heated to 177C for 8 hours (which makes it stronger). There is no way any of the original paint would survive anything like this. Your photo's show that there was no recognized heat treatment. (If they claim otherwise, ask them for their heat treatment procedure, it should be documented). You might get away with a simple weld repair, without heat treatment, in a low stressed part of the frame. For example if the damage was due to an external force above design force, like an accident, that is not expected to happen again. If the damage is a fatigue crack in a highly stressed part of the frame, a weld without post weld heat treatment will be much weaker than the original frame and that crack is going to reappear! Some more interesting reading on Aluminum bicycle frames. https://web.wpi.edu/Pubs/E-project/Available/E-project-042612-124752/unrestricted/Material_and_Design_Optimization_for_an_Aluminum_Bike_Frame.pdf Trashy 1 Link to comment Share on other sites More sharing options...
Mojoman Posted September 22, 2021 Share 2 minutes ago, i24 said: I am very surprised that a responsible manufacturer would have offered "1. Repair". This was never a viable option. It's only purpose that I can see is to deceive a future owner. A typical Aluminium bike frame is made from "6061" or similar tubing. After welding it gets "placed in an oven at 530C for 40 min" then quenched to room temperature (eg in a water bath or spray). Then optionally, re-heated to 177C for 8 hours (which makes it stronger). There is no way any of the original paint would survive anything like this. Your photo's show that there was no recognized heat treatment. (If they claim otherwise, ask them for their heat treatment procedure, it should be documented). You might get away with a simple weld repair, without heat treatment, in a low stressed part of the frame. For example if the damage was due to an external force above design force, like an accident, that is not expected to happen again. If the damage is a fatigue crack in a highly stressed part of the frame, a weld without post weld heat treatment will be much weaker than the original frame and that crack is going to reappear! Some more interesting reading on Aluminum bicycle frames. https://web.wpi.edu/Pubs/E-project/Available/E-project-042612-124752/unrestricted/Material_and_Design_Optimization_for_an_Aluminum_Bike_Frame.pdf I think the hope was for it to last another 12 months then its totally my problem! The guy who did the repair told me he had worked on aircraft doing welds? ???????? Link to comment Share on other sites More sharing options...
i24 Posted September 22, 2021 Share 6 minutes ago, Mojoman said: I think the hope was for it to last another 12 months then its totally my problem! The guy who did the repair told me he had worked on aircraft doing welds? ???????? Weld repairs on airliners are common. BUT, there has to be a documented repair procedure. This has to be signed off by the aircraft manufacturer and approved by the governing authority (eg FAA). The procedure would typically state: What the part is and what damage is to be repaired What weld process to use, current, voltage, gas, filler metal spec etc. Weld preparation and inspection . Weld pre-heat, filler metal preheat and how temps are to be measured and recorded. Welder qualifications (typically welding a similar test sample which is then cut up and inspected). Welder qualification renewal (when was he last retested). Heat treatment (time, temperatures, quenching etc). Reinforcement jigs may be required to prevent deformation during treatment. Post repair inspections (eg X-ray, or dye penetrant inspection) and dimensional checks - in case the part deformed during heat treatment. Post repair coating/painting (another whole procedure). Then there is the paper trail which goes in the aircraft repair logbook: The part serial number, hours flown and number of take off/landing cycles. The above weld repair procedure. Material certificates for the filler material, gas etc. Pre repair inspection report Records of pre heat temperatures. Welder identity, qualification and renewal tests dates. Heat treatment reports. Copy of the chart from the temp/time recorder on the heat treatment oven. Post repair inspection report. All of the above paperwork is subject to getting audited, by the likes of SACAA. So the welder may be very experienced, fully qualified and have a very good idea how to do the work and what process to use. But he is not qualified to write the repair procedure. Also he is likely not the person responsible for post weld heat treatment, post repair inspection etc. This has nothing to do with bike repairs. There above costs way more than a replacement frame, never mind the cost of repainting. Carbon frames are much easier to repair to original strength. It is just difficult to not add extra weight and make the repair look invisible. But this is still a job for skilled/experienced repair guys. Hairy 1 Link to comment Share on other sites More sharing options...
i24 Posted September 22, 2021 Share 1 hour ago, GhostSixFour said: Didn't you say Outsurance was willing to insure after the repair? Did you not get it insured after the first crack and everyone told you it would crack again? Let me guess. Outsurance cover, if it was in place, they would send the bike back to the same guy and get it welded again ... ???? And make you pay excess and loose your "bonus". Link to comment Share on other sites More sharing options...
Mountain Bru Posted September 22, 2021 Share After reading through this thread, I've concluded that bikehub should be rebranded to "Engineers on Bicycles".... Not even being sarcastic. It seems 80% of the guys on here have some kind of engineering background. Link to comment Share on other sites More sharing options...
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