FolderBeholder

Why Brompton doesnt braze a k/s tab on that triangle (or offer it) is a mystery to me.

2_i 

OK, I am back to the base and trying out the Aceoffix ACE Tensioner Wheels. Unfortunately they are absolutely unusable. The outer diameter of the toothed wheel is by 2mm larger than for the original Brompton wheels or for the Best. The elongated teeth, with the elongation there apparently to drill a hole, makes the chain occasionally stumble and fail to climb a tooth an then gradually move completely off the toothed wheel, see photos. In addition, the side retaining wheels do not slope in to push the chain back onto the toothed wheel. Complete disaster. I go back to the Best wheels, resigned that I have to look whether the chain sits correctly after folding the rear triangle in and unfolding - that is the moment when the latter wheels are most vulnerable against a similar chain walk out.



Commercial Photo for ACE Wheel



Toothed Wheels: Best on the Left and ACE on the Right



Climbing Out



Chain Out Free

2_i 

When I encountered the Ti Parts replacement tensioner wheels for Brompton dramatically marked off, I could not resist and got a single one to replace the original Brompton wheel shifted by the pusher to change speeds. The Ti Parts wheels are Porsche-level with triple bearings, inner and outer, rather sturdy and different details demonstrating well more effort gone into their design and manufacturing than into wheels by other brands, such as the Ace junk.

Indeed after I put the Ti Parts wheel on, all was going smooth and dandy, without the hiccups immediately encountered with the other brands absent. Yet after a few weeks of riding with the Ti Parts wheel, I noticed that the pusher would often fail to move the chain to the small cog. Moving the shifter up and down would eventually get the chain where it needed to be, but this started getting annoying. I got the bike into the basement, started analyzing and realized that the bearings were themselves the problem. For the tensioner wheel to get shoved by the pusher, it needs to rotate relative to the tensioner to tame the friction, which is the case for the original Brompton wheels. When the teethed portion of the wheel is riding on a bearing, as in all the aftermarket wheels I encountered, the rest of the wheel quits rotating and can easily get stuck in a single position relative to the tensioner, with the return spring operating the pusher being to weak to unstuck the wheel and pusher combination. The Ti Parts wheel came off and I am back to the original Brompton wheel.

Myself I am Joe Blow tinkering with the bike. If I mess up something, I will myself suffer. These guys, the aftermarket parts manufacturers, without really understanding how the parts need to work, I suspect unfulfilled engineers, mass manufacture failed products, impacting customers all around the world. I am baffled, basically now resigned to the expectation that most aftermarket products in the folding area are not going to work as intended.

Below is the photo of Ti Parts wheel taken apart, from their on-line store:

Jipe

Another bad replacement part for the Brompton: the Nov Design chain tensioner.

First, to save weight it uses a proprietary spring which is lighter but also much weaker than the original one. It can hardly hold the chain tensioned. There is not enough space inside the tensioner to use the original Brompton steel spring.

Second, there is no axle for the moving arm, its the bold that is also the axle and this bold cannot be tightened otherwise it would block the moving arm. The (bad) solution found by Nov Design to avoid that it come completely loose is to use Loctite thread lock.

Third point, to save weight the moving arm is thin aluminum and can easily and permanently be damaged.

This chain tensioner is very expensive and there is an even more expensive magnesium version with threads directly made in the magnesium with the well known sensitivity of magnesium for corrosion, these threads won't last long !

2_i 

Switching from 2 to 3 cogs on Brompton narrows tolerances in the system. While you can set the shifting over 3 cogs fine, it becomes easier for the system to drift out of tune over time. With this you might want to tighten the operation such as by replacing the original plastic Brompton chain tensioner with a stiffer metal aftermarket one. In my case I looked into an aluminum H&H tensioner, sometimes also called the X-tensioner. After putting the H&H tensioner on, I was shocked to find that not only it failed to improve the shifting over 3 cogs, but that it disabled that shifting completely. No matter how fine I tuned the system, what washers, spacers etc. I put on, I could not arrive at shifting over 3 cogs even marginally. The reason turned out to be the distance between the upper tensioner pulley and the wheel axle. In H&H the pulley is pushed away from the axle by about 0.5cm compared to Brompton and then the chain cannot climb from the smallest to the next sprocket when the pulley wheel is put into a central lateral position.

The pulley is presumably pushed away from the axle to allow for a larger maximal sprocket. However you do not know that ahead of time when getting the tensioner. While this tensioner turned out to be a complete waste of funds and time for me, it could still be useful for someone interested in shifting over 2 sprockets only.


H&H Tensioner

Brompton Tensioner

2_i 

When looking for Ti replacement handlebars for Brompton, I wanted longevity there, anticipation that I would not need to replace them during the life of the bike. I was worried about strength in the stem clamp grab area and any potential material defects. I also wanted to preserve the shape of the M-bars, so that I could just move all my installation around the bars onto the new ones. Since the replacement bars vary a bit in dimensions, i looked for ones with a claim of the same or nearly the same elevation above the stem and width as original. I also looked for ones with reinforced stem clamp area.

All appeared fine according to the specifications and photos for handlebars listed on AliExpress. The photos showed the same box-like shape as for original Brompton bars, elevation was the same, width just 1cm larger, but I could trim it if necessary, clamp area was reinforced. When the bars came in after a couple of months of waiting, all seemed fine at first. There was some modulation when I rotated my palm around the tubes, demonstrating that they were not quite round, but this I could maybe live with. Then I examined them in more detail and realized that the angles were not as sharp in the original, yielding a more V-shape than U-shape in the original, in practice wasting usable lateral space. Before putting the new bars on, I decided to compare the new and old bars against each other in more detail.

The comparison revealed other issues than U vs V shape. When aligning the stemp clamp areas, the replacement handlebars rise by 1/2"=1cm+ higher on the left non-drive side than the right drive side. If I actually mounted them, they would cause discomfort in the long term, maybe even down to pain. For Brompton, the left side of the bars would be hitting the ground for the folded bike, as the margin there is narrow. One other issue that came out is that the replacement handlebars are flatter than the original, providing only 3 degrees of backward sweep against about 6 degrees of the original. Even 6 is low and you normally do not want to make it lower.

The general reflection from this exercise is that you may think about possible flaws in the replacement components, but the manufacturers are very likely to blow your imagination. Photos of the original Al and replacement Ti handlebars follow.



New and old handlebars on top of each other


Left side of the new handlebars is by about 0.5" taller than the right.


Original handlebars are approximately left-right symmetric


Backward sweep is twice as large in the original handlebars than in new

Schwinnsta

You could try Kousac (sp) bars. They are not cheap though.

Too add to the thread, I had bought a set of fast after market hinge clamps. After quite some time using them for some time I started to hear creaking sounds. It took a week to find. The clamp on on main tube was not bringing the parts together no matter how tight. It was close but just not tight enough.

2_i 

This has been such a traumatic experience, of a prolonged wait followed by a ridiculously blown balloon, that I will be taking a long break before trying any other product.

In the meantime, after following a trail of photos supplied by the manufacturer, I seem to have identified the latter as COMEPLAY, Baoji Guanheng Titanium Industry Co., Ltd., located in Baoji City. That city houses Bronzeware Museum reflecting history of metalworking in the region, extending over millennia. On a personal note, I visited a famous giant Buddhist site right outside of that city a few years ago, but never got to the city itself. In any case, the specific handlebars appear to be sold by different vendors. To make things worse, COMEPLAY manufactures many other parts for Brompton, including forks, rear triangles and main frames, of which quality I expect to be similar. Oh yes, they are ISO cerified .

BromptonINrio

its a great thread for bromptom owners.
i already saw many.of those aftermarket parts and wanna buy them.
Great to.rear real costumers reviews!

fietsbob

Popping the catch* & folding the wheel under is the kickstand mode.
then it sits on those 2 rollers + the tire, mudguard roller or 2 more rollers on the rear rack


* older models did not even have the catch, rotating the suspension block keeps the catch from engaging,
just like in the old days..

fietsbob

My aftermarket crank came from Switzerland . it's heavier .. 3 speed, 1 cog 1 chainring.
I could fit Tacx sealed bearing nylon pulleys on since they don't get shoved sideways.
My 6 speeds are; a low range reuse of the 3 once again .. internal gears, crank on one side, chainring on the other
So they can rotate @ different rates .. still chain passes over 1 cog, 1 chainring..

Mk 2 bike :



kept it for newer bike



...

FolderBeholder

Thanks.
Now, back to something I DON'T know: why they can't add a small plate for a tradtitional kickstand like I said ( and one that actually works with a loaded rack )

fietsbob

They are in London England and are challenged to keep up with the sales demand of their bikes just like they are ,
If you want to buy one and modify it yourself Feel free . alternatively I've seen a KS that mounts under the rear axle nut
made in Asia you may buy one and add it to yours

a seatpost mounted Beam rack can take all your stuff and still let the rear kickstand fold under..

FolderBeholder

BTDT....Brompton isn't big on evolutionary product development but to answer your not-so-contemporary recommendations the axle bolt stands are woefully unreliable, and of course the seatpost recommendation isn't CLOSE to practical either. Potentially damaging an otherwise precision (needed to fold, as well as support the rider via the consumable "sleeve") seatpost assembly, not to mention requires removal to fold.

I assume you also own a Brompton, and Thank You for providing me the "permission" to modify mine. But I think Brompton is missing a small, inexpensive ability to satisfy those (like me, not you) who might wish to mount a frame-mounted stand to use when the triangle-under parking mode isn't viable, by providing a mounting plate. It's a pretty simple suggestion for which I dont believe an adequate alternative has been provided by the aftermarket (aftermarket accessories, bicycle, motorcycle, automotive you name it, almost always include a compromise of one kind or another.)

Reddleman

Honestly? Kick stands aren’t cool or common in the UK. Most Brommies get loaded up for commuting with the front bag only there and the only times I’ve seen them there with more of a load on has been touring with a rucksack under the saddle resting on the rear rack. Otherwise the rear rack is used as nature and God intended to hold the bike up on the train or in the corner of the office

fietsbob

Well there is one custom shop in Glasgow Scotland making rear sub frames & forks in His Shop, enabling disc brakes & Wider rear hubs
He is a Brompton Dealer.
He has to buy whole Bikes then resells the stock parts . his name Ben Cooper

you might ask him to modify the stock rear portion to integrate a kickstand mount just for your needs, and have it replace the one on your bike..

I doubt you can buy out the whole Brompton company just to bend them to your desires..






...

Schwinnsta

Kickstands at the rear of the bike work better and are not subject to pedal lock up when the bike is backed up. Here is a pic of my bike with a rear mount kickstand that works well.The folding basket has an insulated shopping bag which is full as I took the picture when I was coming back from a trip to the grocery. Here is a link. https://hollandbikeshop.com/en-gb/bi...20-inch-black/

Thanks to 2_i who told me of this stand. Before that I used a Greenfield rear stand which worked fine but was heavy. This one works as well but it beat to fit somewhat but fairly simple.

2_i 

EZ Clamp Spring claims to end 44 years of frustration with Brompton hinge clamps, pushing them away when open, without losing the proper clamp orientation:


EZ Clamp Spring

In testing with a stepper motor the Spring supposedly stayed fine after 8,000 of compression and decompression cycles. Well, I put 2 of those Springs, bought on the EZ Clamp site, to work with 2 clamps on my Brompton. After about 10 foldings and unfoldings of the bike, the first got stuck firmly in postition, see the photo where the gap between the black plastic spring and clamp shows up, and thus quit working. This much for solving the 44y old problem and testing with a stepper motor. I put back my stainless steel spring there, 40x10x0.8, if anyone were looking for an appropriate size.


Stuck EZ Clamp Spring on my bike - worked for about 10 foldings/unfoldings

fietsbob

here is a decent short kickstand it is made into a 2nd kickstand to add to Tubus low rider racks .
you have to hire someone to fabricate a different mount for it .. note the 2 bolts. (# 42 looks like they did that)
'Ergotec' made site says Out of Stock.. (you will see a lot of that due to the current pandemic)


I bought a bike where the OEM got Tubus to make a bunch of racks to build it in..


alternative is the Click Stand it's not mounted, you bring it with you, folded up, and it gives you a support to hold up your bike ..
>light, simple.. <





all 3 are the same length , more sections folds smaller..







...

Schwinnsta

Chinese SS springs work fine for me.

2_i 

Same here, but sometimes I would unscrew too far and the clamp would get misaligned, so I thought I would give the EZ Springs a shot. Obviously you have doubts when you see a feeble plastic going against large metal pieces meant for large forces, but if it worked I was willing to take the risk. When that piece got stuck, it actually momentarily locked the bolt and clamp when I was in a hurry and with no time to investigate what was going on, until a few foldings after. Well, the sooner this kind of items get off your bike, the better, if you can put something more reliable there - the SS springs have stayed there for a year never particularly faltering.

Incidentally, I had there at some point the brass retainers from Speddial and these were bad, getting crumpled by the hinges. I even conversed online with the designer at some point and I thought he was going to drop them, as he was dealing with customer complaints, but I see that the Speddials are still sold with those faulty retainer pieces.

Janne William

you could have a look at the VELLO Speedster titanium, which can go down not so far above that with just the change to a lightweight saddle. Good quality, nice function, 10speed and 20" wheels 👌

Gyrobot

Hi, I can see a few problems :

1. You are not using original Brompton Clamps but looks like the Spédial versions, whatever it is, the bolt looks fully threaded and not smooth like the Brompton originals these threads create extra friction for these springs.
2. You are using V1 of the EZ clamps, EZ Clamp is now on V4 for better compatibility to frame and clamp tolerances.
3. The area looks really dirty and sticky, should be clean and dry.

The reason this EZ clamp doesn't work is not their fault but the fault of trying to fit it to an aftermarket clamp. If you want a V4 version of the spring then reach out to EZ clamp.

2_i 

I already wasted my time and money once and will not waste it again on a V4 prototype. My equipment needs to be bombproof just like the original Brompton is. Clean threads around hinges?! You must be joking. The bike is for use in real life, real streets, where there is dust, rain, mud and snow and no some kind of showcase for a product that is supposed to work if all planets align. Fine details in bolts or hinges?? Products that do not work come off and go to a wastebasket or serve as mementos of where not to go. Products should be for people, not the other way around.

KSG

2_i I am enthralled by your reviews and wanted to impart some gratitude your way for you sharing your discoveries. You've probably just saved me a ton of money and time. I appreciate that.