Fnhon 20" Brompton clone
 

It seems that Fnhon will sell a 20" Brompton clone with disc brakes. As fr as I know, its the first time that Fnhon makes a Brompton clone and its also a complete bike, unusual for Fnhon !?

If the frame quality is similar to the quality of the Fnhon bi-fold frames, it should be a good deal.

The transmission with a nice cassette and derailleur seems also good, I suppose that this derailleur also ensure the chain tensionning when the rear triangle is folded like done with a L-twoo Fold B derailleur?

https://cimg4.ibsrv.net/gimg/bikefor...d53ff0936d.jpg

Here ya go. It's for real if reputable sellers like Delta Cycles are offering it. I'd prefer a Silver frame and build it myself. Price is about $1,250.

https://cimg4.ibsrv.net/gimg/bikefor...a29d9cd58d.jpg

https://cimg7.ibsrv.net/gimg/bikefor...6fd5b96b50.jpg

https://cimg8.ibsrv.net/gimg/bikefor...f6078c667f.jpg

https://cimg9.ibsrv.net/gimg/bikefor...5b4c987b40.jpg

https://cimg0.ibsrv.net/gimg/bikefor...ffce61e9fe.jpg

https://cimg1.ibsrv.net/gimg/bikefor...4dafc3c19c.jpg

Note the absence of a front block, but the presence of bolt holes, suggesting that a separate kit could take care of that.

https://cimg4.ibsrv.net/gimg/bikefor...48e29745b5.jpg

Thanks for the pictures.

They had the excellent idea to make a frame for wide tires just like on the G-line while most other 20" are limited to 1.6"wide tires.

But, crap, its a Brompton style two pieces 10s rear derailleur.

I'm just wondering if a Shimano Alfine 8 or 11 speed IGH can fit in those dropouts...:p

Some more specs : aluminum frame, weight 10.8kg, folded size 80x35x65cm or 75x65x30?, price.

Fantastic! It looks like the ad in Jipe's link has mistakes. It says fixed-height seatpost and adjustable stem post.

This bike looks good.
Wondering about your comment Jipe: "But, crap, its a Brompton style two pieces 10s rear derailleur."
I'm not sure what that means?

Its the same type of derailleur than the Brompton Advance derailleur but with 10s instead of 4s.

Instead of having a cage with tow pulleys, this derailleur has only one pulley to move the chain, the second pulley is on the separate chain tension arm and is laterally sliding.

Knowing the problems of this kind of derailleur with only 4 cogs, i am afraid that it won't be reliable with 10s because too sensitive to dirt, mud...

Ah - thank you for the explanation. I guess it's a case of swapping in another 10 speed set up? Apparently there will be some sort of rear rack especially for the GT20 later this year

Plausible insight. I have test ridden G-line speeds and encountered no problems shifting, Nor have I heard of any.

Yeah I saw that too, I had not seen that design before, so first question to me is availability of replacement parts, especially for a non-standard mount.

I also saw fine print just forward of the diagonal to the bottom bracket, saying aluminum. I'd prefer chrome-moly steel. However, notice the higher quality weld at the upper seatpost (versus the other TIG welds), a feature we have seen before on Zizzo aluminum frames, where fatigue strength at the weld transitions has been a problem on Dahon aluminum frames. Dahon's Archer Pro seems to show such smooth welds, but is unavailable in north America.

My gold standard for any clone is that it is below 50% genuine price; 349 Brom clones have not met that, and have not nearly the warranty and service of Brompton, so in that case, no more than 33% of genuine price. Now this clone, versus the much more premium price of the Brompton G, may meet that criteria, and, that cost delta being thousands and not hundreds of US dollars, means it may be competitively viable.

If the gearing does not meet 400% range minimum, I'd be looking at the seat post outside diameter, and availability of front derailleurs or adapters available at that diameter.

Dahon's warranty and service is much worse than Bromptons, so that clone price is competitive, plus it doesn't have the Dahon 15mm inboard offset brake discs and calipers that make a brake upgrade very expensive (new calipers AND new hubs and wheelbuild, or new wheels).

Those look like RivNuts, which is more sound than threads into a thin-wall tube; I've replaced stripped threaded holes on aluminum sailboat masts with stainless steel rivnuts. They work sort of like expanding hollow-wall anchors (aka Molly Bolt), but stronger. However, the expanded head inside the tube, is not nearly as much area as a welded block, so any adapter mounted to the rivnuts is still not as strong, not in pullout strength, but in lateral wobbling of your front mount with cargo, and I might expect the head tube to fatigue crack around those holes. Perhaps not if the threads are only used in tension, and the mount stabilized with contact against the head tube itself.

With big cassette gearing, should be the right O.L.D.! The problem with Broms has always been their narrower standard. However, notice a) thru axles (for disc brake safety), and b) nothing slotted or eccentric to provide chain tension, so dummy-derailleur might be needed for that, but then again, is also necessary for chain tension in folding. Can you get Alfine hubs with a thru-axle? (and disc brake, I've seen one with their roller brake and after doing a deep dive on that, passed on the bike despite low price used, the hills here would wear it out too quick).

On the Brompton G-line, the "lug," if you can call it that, is inside the steerer tube. I clipped a photo of the G-line from a Brilliant Bikes video.
https://cimg6.ibsrv.net/gimg/bikefor...045968e38e.jpg

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Interesting, thanks! I also noticed on the clone that the O.D. of the head tube was straight-wall, so thought perhaps thicker in the area of the threads/rivnuts, with recesses for internal headset bearings. But your photo of a Brom G shows just thin wall tube. 349 Broms had an externally brazed front block, so that represents a departure, and possibly different mount interface geometry on the G. The head tube is really highly stressed, I don't know if I'd want that thin a wall.

The rear on their tri-folds isn't a thru axel, so it would work just fine. The same for a chain tensioner, like I used to have on my single speed to 3 speed conversion. And they come with disc brakes as well. I have discs on my 3 speed Shimano igh that I'm saving, and a 7 speed I have stored away. All these igh hubs have the option to get them with disc brakes.

Yes to all, but that Brompton clone shown above, appears to have thru axles front and rear, either that, or not but with some nuts on both end that sleeve over each end of the axle where it interfaces with the dropouts. Not sure. They don't appear to protrude enough to the outside to be normal nuts, and there's no slots at the dropouts.

Apologies, I haven't read any posts. Has it been observed that most (all?) Brommies are 16"? This bike at 20" is gonna be big. Heavy as well. I wish the press photos showed it next to something for a size reference. The price is double that of my present Giant Expressway and I thought that was pushing the envelope. Yeah, a frameset that could be built out with parts box/discount components would be the sweet spot for me.

Announced at 10.8kg, its not heavy and, even if its bigger than 16" tri-fold, its still smaller than 20" bi-fold.

What is gained in weight, is partly negated by the ability to use all-external gearing, being able to get by without an "overdrive" required for the smaller wheels. A lot of custom makers and Asian frame suppliers were making Brom clones on 406 wheels before Brompton jumped in. Additional benefits are ability for wider tires, and that and the larger diameter make off-pavement more possible, hence the Brompton designation of G-Line (Gravel).

I'd always wanted a 20" brompton, but at $3500 they killed my interest. Eventually I'll get a clone. I'm just waiting for the build quality to be good enough. I'm not overweight any longer, but I like a bike designed to carry heavy loads. That's why I have my Origami Bull. Come summer I'm RIDING!!! :ride: