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Old 01-02-19, 06:50 AM
  #9  
berlinonaut
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Join Date: Mar 2016
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Originally Posted by Raxel
It does have front luggage mount, which TW Brompton lacked.
This seems not to be entirely true, following an old website.

Originally Posted by Raxel
-Titanium clone frames are not inexpensive (I paid like $2K) but they are actually very good value considering the weight savings (roughly 1.8kg over full steel version). The Nikel plated Brompton with ti fork and rear frame is around $3.5K here. My total build costs around $4K, but is 5kg lighter. According to my calculation I can make the whole bike as light as 5.1kg with current frameset if I go up to 11 (and some people do nowadays!)
Would be interesting to know what the weight of the frames is. An Mk4 Brompton main frame weights about 2,1kg, the Brompton fork 560g (steel) or 260g (titanium), the Brompton rear frame 800g (steel) or 480g (titanium). The stem differs depending from the model - an S-stem weights about 880g, an H-stem about 910g, P and M about 810g.
A full steel Brompton frame including M-stem (as yours), forks and rear frame would therefor be roughly about 4,27 kg, the ti-version ~3,53 kg.
If the ti-clone does safe 1,8kg over a steel Brompton it would therefor be around 2,47kg and - assuming that Brompton ti-parts (fork and rear frame) and equivalent clone ti-parts would weight around the same - save about 1,18kg on frame and stem which equals around 40% of the weight of a steel Brompton main frame + M stem (~2,9kg). Quite impressive.

Regarding the "5kg lighter": A stock Brompton M2Ex (2-speed ti w/o rack, lights and blades) like your build weights around 9,7kg. With your build being 5kg lighter you should end up clearly below the 5kg mark... Regarding the price: If you want to have a shiny silver main frame on your Brompton indeed the Nickel Edition is the only factory choice. But as it is far more expensive than an "ordinary" ti-Brommi a price comparison to your build would rather be with a ordinary model. In this case you would have plenty of money left to upgrade to the same lighter parts that you use on your build (and even more if you'd sell the stock parts). So in the end the weight difference will end up at about the weight difference between Brompton frame and stem vs. Clone ti-frame and stem. Which still may be impressive enough.
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