danoulz

I love my Brompton M6R+ ! It's fun to ride, the handling is good, it's comfortable enough, the luggage carrying capacity is great, and last but not least, the small footprint when folded puts the B in a class of its own.

If money was no object, I would buy another one for my wife. However she is not a keen rider so I needed something cheaper: here comes the Merc !

I am well aware that the Merc is cheap in terms of price *and* quality, but I was actually quite exited to discover what the fuss was all about. I also thought it would give me a great base to experiment with incremental updates, something that I don't fancy doing on my new-ish Brompton.

The aluminium frame is light and strong, the quality of the welding is good and the hinges look robust. It all seems like a durable package, and according to Merc owners this is effectively the case.

However some components are just dreadful ! The prehistorical single-pivot brakes are useless (dangerous in fact), the pads and cables+housing are cheap, and the saddle is a piece of junk. The seat post tends to slide downwards while riding, unless the clip is really tight. There are tricks to make it reliable but it's a bit of a pain.

The factory tyres handle just fine, but they need to be inflated over the rated PSI to be satisfactory. The wheel spokes are too thin and will bend or snap because of the high tyre pressure.

There's definitely flex in the handle bars and post, but to be honest not much more than my B. The grip-twist gear shifter is the usual matter of taste. Personally I think it interferes with other riding functions. The folding pedals are cheap mainstream plastic ones, but they work. The Brompton aluminium pedal design is more laterally compact though.

On the bright side, the Sturmey Archer 3-gear hub works fine, and I find the rounded hinge clip rotating handles more practical than the straight ones. The rear rack, roller wheels and mud guards are decent, on a par with the B. The front luggage block works perfectly with my Carradice/Brompton gear. My wife prefers the kick-stand to the "garage" half-folded position, so here y'a go

I notice that the fold is different (i.e. not as compact as the B), maybe because of quality control issues, manufacturing tolerances, or just plain dysfunctional cloning For example, the chain tensioner sticks out too much and prevents the front wheel to fold closer to the bike (note: I have the upgraded aluminium tensioner). On my Brompton, I have stubby bar ends and they fit fine when folded without adding volume. On my Merc, I think they would interfere with the wheel.

I don't have the dynamo lights so I can't comment on that.

Overall, I like the price/value ratio and I am looking forward to piling-up miles to put it to the test. Until I'm bored that is, or have a bit more cash and purchase another Brompton

Enjoy your rides.
Cheers, Dan

somnatash

Hi Dan,
Thx for this nice comparison and valid points I am curious about your findings in the long run - stay tuned

I only disagree with this point: I prefer the straight handles over the round ones because:

On a side note, just an idea: On partner rides, let your wife ride the lighter/better/more geared...bike since she is probably weaker then you. Letting her ride the better performer would balance a little of the strength difference. Also she obviously needs more support/stimulation than you to like biking more and to become a keen biker as you are. Having the better bike perhaps helps with that.

jur

This doesn't sound right. It sounds like the spokes need to be tensioned. Tyre pressure has a tiny effect on spoke tension. What do you mean?

danoulz

Yes. I will also make sure that she gets to ride both bikes alternatively, so she can judge by herself. We will probably ride on flat surfaces to start with, so the experience will be mostly positive. I think she'll find the Merc's 3-speed twist-grip shifter easier to use than the Brompton's 6-speed double-lever setup.

She seems exited about learning the fold/unfold techniques, which is cute !

danoulz

Yes, I realize that I'm wrong. In my haste I assumed that a harder tyre would create more stress in the spokes when riding over potholes. The main factor is obviously not that, but a bad wheel. I will take the rear wheel to a cycle shop so it gets rebuilt. The front one is tensioned uniformly, as much as I can tell.

EvilV

I broke five spokes in my Merc rear wheel over about the first 1800 miles. I've done almost another 1700 with no more breakages. I think the wheel wasn't properly tensioned when I got it since it has been fine for so long now. In the early days of Brompton they used 14 gauge spokes, but after a lot of breakages, they replaced them with thicker 13 gauge ones. I think this happened around the early nineteen nineties - but at any rate, it was a long time ago. Merc is based on the early Bromptons and doesn't have the stronger wheels. I think the rear wheel is especially prone because of course it transmits the heavy torque when accelerating away from traffic lights and also, the small wheel and wide hub create a steep spoke angle at the rim. Brompton spokes fit right into the merc wheel if you do break any. You can also put in the larger 13 gauge spokes.

I agree about the brakes. Koolstop salmon pads will make a big difference and either lubricating the cables or replacing them as SesamiCrunch did, will make them a lot better too. When I first got my Merc, I had a few unpleasant experiences when it wouldn't quite stop when I'd been going fast down steep hills. It would slow right down but just keep rolling at about 5 mph no matter how hard I squeezed. Get some salmon compound pads and it will be much better. Also, clean the rims with citrus degreaser and let it get on the pads. That makes them a lot more grabby. A women will need better brake power than a man since she probably has a lot less hand grip strength to force the damned thing to stop, so I would make the braking a priority for modification. I think the Brompton double action calipers will fit. It's probably enough just to replace the front one, I should think. I'm happy with my brakes now though after the pad change and cable lubrication.

jagatron

I did the same thing for us; esp with new minimum prices for getting into a basic Brompton.

danoulz

I added a couple of photos of both bikes:

https://www.bikeforums.net/showthread...33#post7721133

ShinyBiker

Thanks for the write up. Where are you located? Where did you buy the Merc and how much? thanks.

danoulz

I'm in the UK. I purchased both the Merc and the Brompton as private sales, from London. I also keep an eye on eBay to spot a bargain. There are many Bromptons for sale in the classifieds, mostly in London. A lot of them are cheap...because they're stolen. There's a huge demand for these bikes so there is a lot of fraud as a result. If only Brompton would fix its supply chain (decrease the lead times) and lower their prices a bit...

jagatron

Is there a good online source for where to spot these in classifieds in the UK? 'Travel there on business and it would be easy to arrange this. Thanks.

EvilV

Maybe you missed the phrase after the word 'cheap'. He said, ' a lot of them are stolen.'

1-2-many bikes

Hi Dan - Adam here. just come across this thread saw your right ups / reviews of the old Merc - how you finding the Merc now? Must say i miss it a bit but dont have to commute for a while as a plus side!

danoulz

Hi Adam ! Nice to hear from you again. The Merc is fine. I spent a couple of hours on TLC to enhance a few things. I've cleaned-up the gear hub, torqued-up lots of nuts, etc. I've re-arranged the cables around the handle-bars and frame, so that folding the bike doesn't bend the cable housings. I followed the design on my Brompton to attach the cables together in specific locations. The cables on the Merc are too long actually, I will shorten them when I upgrade the brakes (my wife enjoyed the rides, except the brakes which are useless).

Take good care of yourself, cheers, Dan

bykerouac

Excellent comparative thread Dan! I think if you tweak your Merc a bit you will approximate the Brommie's fold. How much lighter is the Merc compared to the B?

danoulz

The frame itself is lighter (it's aluminium instead of steel/chromium), but the cheap components add weight so I think they weight the same in the end.

somnatash

hum, I guess not even that. Actually not the fork, not the steering stem nor the rear triangle but only the middle part, the main frame is of aluminium - that part is 300 gr lighter than the brompton steel middle frame.

danoulz

That's what I meant by the "frame".