Originally Posted by
Raxel
Root cause is a bad design (thin titanium steerer tube + archaic conical expander nut that puts too much stress on a line, not a wide surface), not overtightened stem.
Ti-Bromptons do exist since 2005 - the issue seems to be pretty new. Maybe a coincidence after moving production of ti-parts back to the uk a couple of years ago. It thus is not a generic design issue but one of maybe having choosen a wrong tube or having had a bad series of tubes. Should definitively not happen, that's for sure.
Originally Posted by
Raxel
It is almost meaningless to tighten the expander nut using the torque wrench as the friction between the nut and tube is huge.
I personally do own two ti-Bromptons and -as far as I know - they do not have those issues. And I have had no issues tightening the nut correctly until now.
Originally Posted by
Raxel
Brompton SILENTLY changed the expander with a wedge for this year to handle this issue
One calls this process continuous improvement and it comes from Japan... Out of curiosity: How do you know about the silent change when it was done silent and secretly?
Originally Posted by
Raxel
They are not my bikes. Owners did place warranty claims and the local dealer said those Bromptons are modified (disassembled) by third party so they lost warranty. Fun part is that one cannot know their steerer tube is intact before taking the fork apart. They got a ton of flak for this policy and I think owners got them replaced eventually.
This is an issue with the local dealer and his tolerance I'd say. Or maybe he knows his customers and their abilities - obviously cannot tell. And from one possible perspective he might be correct: If a third party does work or maintenance on a bike during warranty that is not average service work (which pulling the fork is clearly not) - how would one know who caused the problem. The good thing about not knowing about the issue before taking the bike apart is obviously that it does not lead to a dramatic accident immediately. But obviously a failure like that is beyond any tolerance. According to European law an issue like that that pops up during the first six months after purchase would be assumed to be caused by the seller/factory unless they would be able to prove otherwise. This is the law, independent from any warranty that may be given by the manufacturer or not.
Originally Posted by
Raxel
All others do as well.
Dahon i.e. is famous for not doing so. Look i.e. at the thread in this forum dating from 2012 when Tern was founded and how people were joking it would would be a main differentiator from Dahon it Tern would actually offer spare parts.
Would be interesting to see how well 360 is able to handle warranty and support and spare-parts topics.