Does this look like a crack? Momsen Al129 -2018 model

[GhostSixFour]

33 minutes ago, Mountain Bru said:

Clearly someone isn't an engineer..... ????

But I do agree. Being an expert in one thing in no way suggests you're competent at anything else. 

I'll never forget at a engineering conference a few years ago where Pat Morewood spoke about how he designs bike frames. It was quite a techy conference, so all the other talks had been on complex ways to use software in design, and then Mr Morewood got up and his answer to "how do you design bikes" was basically "I draw it on a piece of paper, and then we make a prototype, and then I sit on the bike and decide if I like how it feels". There was audible confusion amongst the group of engineers that are used to analyzing everything to death. Such a good example of how being a "analysis expert" in no way means you're good at sitting on a bike and deciding if the geometry is good. 

I mean, with a name like that, he must be a hairy finance specialist right?

[DMJ]

One would expect Momsen to respond here and to inspect the bike and take care of the issue.

[Steady Spin]

@Mojomanhave you given them flack on social media yet? 

After this i'm really glad I didn't buy that Vipa

[Mojoman]

22 minutes ago, Steady Spin said:

@Mojomanhave you given them flack on social media yet? 

After this i'm really glad I didn't buy that Vipa

I did message Momsen on FB half way through this mess...:
"Best place to start is the Dealer who you purchased it from. All info is on the Momsen Bikes website too"
????
 

As it always seems to be...once you have paid...
You are on your own....
(if you go through this site there are a good few complaints on Momsen/TWT....history just repeating itself here!)

Edited September 23, 2021 by Mojoman

[Steady Spin]

Time to start reviewing them everywhere I guess. 

[Trashy]

2 hours ago, Mountain Bru said:

Clearly someone isn't an engineer..... ????

But I do agree. Being an expert in one thing in no way suggests you're competent at anything else. 

I'll never forget at a engineering conference a few years ago where Pat Morewood spoke about how he designs bike frames. It was quite a techy conference, so all the other talks had been on complex ways to use software in design, and then Mr Morewood got up and his answer to "how do you design bikes" was basically "I draw it on a piece of paper, and then we make a prototype, and then I sit on the bike and decide if I like how it feels". There was audible confusion amongst the group of engineers that are used to analyzing everything to death. Such a good example of how being a "analysis expert" in no way means you're good at sitting on a bike and deciding if the geometry is good. 

I think Pat was exaggerating, at least a little bit. Even in the Morewood days (apart from the very beginning) the designs went through software analysis. I can't imagine things went backwards when he started Pyga, but perhaps I'm wrong.

Your point remains though that he takes a very hands on approach to design, where software and analysis supplements hands on development and feel.

[MORNE]

6 hours ago, Jewbacca said:

I disagree.. Being a specialist in one field doesn't always translate into other specialized fields.

Designing a 25000 seater stadium out of system scaffolding that can survive multiple earth quakes doesn't make one in any way qualified to comment on bike design with the same authority. 

Much like a web designer or software engineer cannot start picking apart another platform without seeing the flow charts and data.

I think THAT is what happens here. People use their knowledge to make massive assumptions with the authority of a qualification without being privy to all the relevant and important data.

That's just me. I think a lot of why people are starting to find this particular site 'boring' is because a lot of the current locals spend a majority of their time whinging about the same stuff on repeat, which means any interesting threads that do pop up land up being ignored or very quickly turned into the same whinge fest. 

I'm not pointing fingers, I think we are all somewhat guilty, some more than others. 

This kills discussions and the weight of opinion makes it difficult for people who might have valuable input to comment. I dunno, It's just a trend I've started to notice.

Look at me, whinging about people whinging!!! ????

its only a bicycle. Though alot of what you say is valid for a lot of industries you mention....design is design is design imo, and if you have been schooled to think like a designer, it's quite easy coming up with solutions to any problem. The thought process and way of working through a design problem is EXACTLY the same..the inputs just change.  So being an "engineer" does not necessarily mean you can design - although a lot of them think they can lol. All they see is practicality, efficiency, numbers and analysis. Design is the glue that makes all that work together. 

I have more respect for someone who builds a prototype, draws out something on paper, puts togethers models as part of the ideation/prototyping process than someone sitting in front of a PC feeding numbers into what ever godawful CAD machine. 

PS - As far as i remember you are busy DIY'ng one yourself lol 

also: it's 'whinception' damnit

[ChrisF]

1 hour ago, MORNE said:

its only a bicycle. Though alot of what you say is valid for a lot of industries you mention....design is design is design imo, and if you have been schooled to think like a designer, it's quite easy coming up with solutions to any problem. The thought process and way of working through a design problem is EXACTLY the same..the inputs just change.  So being an "engineer" does not necessarily mean you can design - although a lot of them think they can lol. All they see is practicality, efficiency, numbers and analysis. Design is the glue that makes all that work together. 

I have more respect for someone who builds a prototype, draws out something on paper, puts togethers models as part of the ideation/prototyping process than someone sitting in front of a PC feeding numbers into what ever godawful CAD machine. 

PS - As far as i remember you are busy DIY'ng one yourself lol 

also: it's 'whinception' damnit

 

For my sins I "was volunteered" to mentor our young engineers ....  

 

We appoint a guy with about 4 years post qualification experience, and put him to work on a nice entry level project.  Not long before he brings me his "design" ....  I do the typical quick rule of thumb cross check ..... OOOOOO cr@p, the system is UNDER designed by a factor of about x20 !!!

 

Breeeeath .... a mentor should assist and guide, and all that ....

 

So we go back to basics and I take him through the steps ..... NOPE.  He assures me he KNOWS this stuff, and have been doing it for "years", and he TRUSTS his answers !!!   Then he tells me he used "the design software, so the answer MUST be right...."

 

 

 

Reminds me of my days as a student with Dr Less Rencontre.  He did his doctorate in designing stress analysis software.  MAN, was he passionate about getting a "feel" for the reality, and NOT blindly trusting the computer output !!!

 

 

 

[Hairy]

3 hours ago, ChrisF said:

 

For my sins I "was volunteered" to mentor our young engineers ....  

 

We appoint a guy with about 4 years post qualification experience, and put him to work on a nice entry level project.  Not long before he brings me his "design" ....  I do the typical quick rule of thumb cross check ..... OOOOOO cr@p, the system is UNDER designed by a factor of about x20 !!!

 

Breeeeath .... a mentor should assist and guide, and all that ....

 

So we go back to basics and I take him through the steps ..... NOPE.  He assures me he KNOWS this stuff, and have been doing it for "years", and he TRUSTS his answers !!!   Then he tells me he used "the design software, so the answer MUST be right...."

 

 

 

Reminds me of my days as a student with Dr Less Rencontre.  He did his doctorate in designing stress analysis software.  MAN, was he passionate about getting a "feel" for the reality, and NOT blindly trusting the computer output !!!

 

 

 

what you described is essentially just another day if you have a teenaged son who thinks he knows everything.............

[Mojoman]

Lol...still no payment/refund from Momsen/TWT...
Quality 'South African' service levels...????

Edited September 28, 2021 by Mojoman

[DJuice]

18 minutes ago, Mojoman said:

Lol...still no payment/refund from Momsen/TWT...
Quality 'South African' service levels...????

Hope you get sorted soon.

I decided to vote with my money and no longer support Momsen/TWT.

 

[mazambaan]

On 9/23/2021 at 4:44 PM, ChrisF said:

 

For my sins I "was volunteered" to mentor our young engineers ....  

 

We appoint a guy with about 4 years post qualification experience, and put him to work on a nice entry level project.  Not long before he brings me his "design" ....  I do the typical quick rule of thumb cross check ..... OOOOOO cr@p, the system is UNDER designed by a factor of about x20 !!!

 

Breeeeath .... a mentor should assist and guide, and all that ....

 

So we go back to basics and I take him through the steps ..... NOPE.  He assures me he KNOWS this stuff, and have been doing it for "years", and he TRUSTS his answers !!!   Then he tells me he used "the design software, so the answer MUST be right...."

 

 

 

Reminds me of my days as a student with Dr Less Rencontre.  He did his doctorate in designing stress analysis software.  MAN, was he passionate about getting a "feel" for the reality, and NOT blindly trusting the computer output !!!

 

 

 

This comes up quite a bit - one SA university even had a lecturer who missed some very basic stability issues in structural design. He just disappeared.

But to bicycles; I suspect Pat Morewood can just draw out a frame and build it to see if it "fits" but the devil may be in the detail; mainly the stress analysis for member sizing and connection design and manufacture. Seems to me there are two points of frame failure - the member itself it is is under sized (over stressed) and the connection in that it does not distribute the stress evenly within allowable limits. But maybe that is simplistic, understanding what the loadings are must demand experience and deep knowledge; maybe running an instrumented frame.

[dasilvarsa]

Accidents cause a lot of the failures in aluminium MTB frames.

The High Torque Stresses the Weld and the Cracks are only Visible some time later.

If you catch it Soon Enough is is Fixable by the Right Welder.

[Trashy]

38 minutes ago, dasilvarsa said:

Accidents cause a lot of the failures in aluminium MTB frames.

The High Torque Stresses the Weld and the Cracks are only Visible some time later.

If you catch it Soon Enough is is Fixable by the Right Welder.

Even if caught in time, you would still have to heat treat the frame after the welding repair.

[dasilvarsa]

22 hours ago, Trashy said:

Even if caught in time, you would still have to heat treat the frame after the welding repair.

The Damage Was due to an Accident where the Saddle Was Totally Destroyed.

Welding was done by a Professional Engineer.

4 Years Later Some Extreme Riding and Still Holding Up.

Edited September 29, 2021 by dasilvarsa

[RustyHWR]

Maybe i was just lucky, but TWT / Momsen  refunded me in full (purchased price) for a Momsen GP300. Had a problem with the hanger on the frame that could not be fixed. Replaced the hanger a few times with no luck.