Custom lots-of-titanium Brompton

I'd say that's a pretty fair summary, yes! However, the trouble with the calipers is that they're rather unusual in that the cable enters from the bottom. It's possible to re-route the cables so they enter from the top, but that rather screws up the fold and so doesn't make it work better. It's possible to bodge an adjuster and clamp onto standard calipers to reverse the cable direction, but as you can probably tell from the word 'bodge' I don't find that option particularly aesthetically pleasing.

If I find some billet titanium upside-down cable calipers, I think there's a fair chance they'll make it onto the bike. But at the moment I haven't.

there are alternatives but i don't want to share my secrets ;)

The upside down calipers are definitely necessary if you're going to carry luggage on the front, but others claim that you can use top pull calipers (at least on the front) without affecting the fold. That has to be a much more efficient cable path, and avoids the water trap of the normal cable loop.

Surely you'd just put a disc brake up front.

^ This.

Ryan of Oak Cycles is experimenting with that and an Alfine 11.

Braze on v-brakes so your brompton can look like this one? ;-) http://www.lfgss.com/thread27801.html

Brazing titanium would be quite tricky.

To be honest, I've never felt the brakes on the Brompton to be particularly lacking. They're not brilliant, but they do the job. Must be my mighty upper body strength.

Oh, and I do occasionally use the luggage block on the front, so bottom-entry calipers are a necessity.

Different levers can make a nice difference to the brake performance I reckon.

I hope this project hasn't gone quiet!

I'll bump it along with a mention of these brakes which apparently have been fitted to some bromptons, the TRP 925.
http://www.trpbrakes.com/category.php?productid=1031&catid=182

They look quite nice and are side pull, avoiding some of the problems of the Brompton original bottom pull or alternative top pull calipers. They also have long reach, especially the front model which is designed to sit behind the fork on a normal frame.

I suspect there are all of the usual problems with bolts / lengths / recessing... and I don't think they'll play nice with mudguards...

oh well... those Brompton calipers aren't so bad, are they now? ;-)

I've just bought a new Brompton and the new brakes are actually pretty decent. A huge improvement on older models I've ridden.

Given how small the wheels are on a Brompton any old brakes will do.

I've got a Dawes KinPin with steel rims, and even with the crappy old side pulls stop it pretty quickly.

I hope this project hasn't gone quiet!

I'll bump it along with a mention of these brakes which apparently have been fitted to some bromptons, the TRP 925.
http://www.trpbrakes.com/category.php?productid=1031&catid=182

They look quite nice and are side pull, avoiding some of the problems of the Brompton original bottom pull or alternative top pull calipers. They also have long reach, especially the front model which is designed to sit behind the fork on a normal frame.

I suspect there are all of the usual problems with bolts / lengths / recessing... and I don't think they'll play nice with mudguards...

oh well... those Brompton calipers aren't so bad, are they now? ;-)

Any pics or blog entries of this being done?

Any pics or blog entries of this being done?

It seems straightforward. I believe you would need two front brakes, and potentially drill a hole to reach the correct height:

Recessed nuts would not be a problem, as it appears you can use a non-recessed bolt instead.

Hmmm,

Doesn't look like you would be able to get the mudguard through (which was mentioned).

It's one of the major reasons I like the Brompton; it doesn't look stupid with the guards (unlike most bikes).

Hmmm,

Doesn't look like you would be able to get the mudguard through (which was mentioned).

It's one of the major reasons I like the Brompton; it doesn't look stupid with the guards (unlike most bikes).

Hmmm,

The Brompton is definitely one of the most difficult bikes to mod without compromises. There are other ways to use different brakes with mudguards, but the recessed nut becomes an extra (though simple) step to deal with...

Perhaps for some people it is better/simpler/cheaper to stick to Brompton's original configuration, as it guarantees that everything will work and there is no need to be picky.

I hope this project hasn't gone quiet!

Fear not, progress is still being made (albeit slowly). I'm waiting for a load of titanium bolts to swim over from Taiwan and China, after having decided that Ed's scepticism of my plan to use ali bolts was well-founded. And because it means more titanium. Yay!

This location is very addictive.
https://www.facebook.com/pages/Ti-parts-workshop/405701912835007

Right, update time. Although the finish on the carbon mudguards was reasonable I decided it would be better to lacquer them, so gave them several coats of Polycote Clear, sanded them down with 1200 grit paper and then polished them up again. The finish isn't perfect - I probably should have bitten the bullet and used some proper 2k lacquer - but it's good enough. I've also ordered in the bolts I need to replace the steel bolts provided with the mudguards with titanium bolts, washers and nuts. Most of them are from the UK, but some I ended up having to order in from the US and Taiwan.

I'd already got some titanium bolts as part of my Brompfication order. For example, these bolts:

(from left to right, stem clamp bolt, stem main bolt, stem catch bolt) will be replaced with

saving an enormous 23 grams. Brompfication have also started producing a fourth bolt in titanium (the suspension block bolt) which is included in a kit with the other three bolts I already have, so I'll have to see how much the fourth bolt would cost by itself.

As well as just buying stuff in, I've also used some titanium plate I had in the scrap bin to replace little steel parts which come with the mudguard fitting kit. For example -

the mudguard stay is titanium, but the standard Brompton kit the bolt and the small retaining plate are BZP steel. So I've replaced the bolt with a titanium one, and made up a replacement retaining plate. There's also the steel reinforcing plates which go on top of the mudguards:

I've made up some titanium replacements:

resulting in a massive 6 gram saving.

Now it's time to fit the mudguards, which means fitting the brakes, and then I can fit the wheels and decide how much (if at all) the handlebars need to be chopped down by.

Totes insane! Love it when these older projects come back to life.

Some more steady progress. The front mudguard and brake are now in place:

as are the rears:

All of the bolts and nuts are now titanium, except for the retaining nut on the rear brake which also has the seat post stop mounted onto it (the black one in the picture above) which is an ali Bromfication part, and the countersunk bolt holding the rear roller wheel in place. That needs to be an M5x25mm countersunk bolt, and due to ordering cock-ups on my part, I have M5x20mm and M6x25mm titanium countersunk bolts, but no M5x25mm. Some are winging their way over from China.

With the wheels in place I could do The Fold and see how much the handlebars needed to be cut down by.

So far I've decided that they don't, so I could start fitting things to them. In this case, the SA gear shifter for the rear hub, Paul E-Levers and Brooks grips. The Paul levers were the wrong size - they were for 23.8mm bars, and the titanium bars I've got are 22.2mm - but I made up some shims with some 0.8mm brass shim stock. The shims are just above visible in this photo:

This is where the bars have got to now:

Next up, cables and chains. But I need some more parts from furrin lands first.

Those grips look kind of heavy. ;)

Looks can be deceptive! They weigh 118g for the pair according to Brooks, which is about par for the course for lock-on style grips.

Looks superb, thanks for the updates.

Really want to see a pic of this bike. All of it. In one shot. Call me old fashioned.

^ this. awesome bike

Shoulda had it all nickel plated, mind. Except the rubbery bits.