Custom lots-of-titanium Brompton

Loving this build.

I'll be interested to hear how you get on with those brake levers. I reluctantly took mine off after a few wet weather close shaves where I was struggling to stop in time - even with swissstop pads. I dunno if Brompton have improved the calipers since then though...

#weakfingers

Full shot of the bike once it's finished. Only teasers until then.

As for the brake levers, I'm not entirely convinced that they'll provide the stopping power required, but if they don't then I can always change them. The chap I bought them off said he'd fitted some to a couple of Brompton builds and that they worked well, but then again he would, wouldn't he?

Those are some wide bars. You could probably take a couple of inches off each side easily... at which point they'd be more similar to the S-bar. The S-bar only goes beyond the diameter of the wheel by an inch each end.

They are quite wide. They're 600mm wide, and the S bars are 52.5cm wide, so these are 3 inches wider overall. The first photograph is slightly misleading due to the perspective - the bars don't actually stick out beyond the frame/wheel.

The extra width doesn't appear to affect the fold, and provided I can still squeeze the Brompton into the spaces it's used to being squeezed into at home, work and on the train I think I'll stick with the extra width for now. It is, after all, much easier to chop a little off the ends of the bars than to add it back on again later...

Get some ESI racers edge silicone grips on there, sub 50g and they'll be comfier than those brooks ones.

Nah, not nearly shiny enough. I'm carefully balancing my weight-weenyism here with my magpie tendencies...

Nice project*. I'm a bit surprised by the tyre choice though. Regular Marathons still have very adequate puncture protection paired with a better ride quality and a lighter weight than the Pluses.

*sorry Skully

According to the Schwalbe website, the 16" Marathon Plus weighs 480g and the equivalent sized Marathon is 420g.

The reason I've gone for the Marathon Plus is because of the excellent puncture protection. Despite the ti bling, this bike is essentially a utility bike, and I switched to Marathon Plus tyres on the rat Brompton after a succession of punctures using Kojaks. I haven't had a single puncture (tempting fate, I know) with the Marathon Pluses despite the streets of Kings Cross being paved with broken glass. Punctures, especially on the rear, are a real PITA on the Brompton, and so I'm happy to bear the extra weight in return for the extra puncture protection on the Pluses.

Marathon rear, Kojak front?

Front punctures less of a PITA than a rear puncture, but it's still a PITA. Based on my experience so far the Marathon Pluses mean I simply don't have to worry about it, which is nice.

Fair enough, can emphasised with that.

You got less weight on the front thus lower risk of puncture hence the suggestion, or even marathon plus rear and standard marathon front.

Where are the handlebars from? It looks a lot longer than the one Bromptification offers...

J&L titanium bars from Taiwan via eBay.

Well reminded that man.

Since the last post, I discovered a place called Ti Parts Workshop in Hong Kong who do a range of titanium bolts for Bromptons. Selecting the ones I hadn't already bought from Brompfication, I ended up ordering these:

http://www.zen118609.zen.co.uk/SuperBrompton/tibolts1.jpg

Clockwise from bottom left we have (1) the bolt, washer and nut which holds the rear suspension block in place (2) the nut which goes at the end of the Sturmey Archer hub (the one with the hole running across it) (3) some M10x1 nuts for the ends of the SA hub (4) a full set of titanium bolts for the Brompton brakes (5) the pivot bolt for the chain tensioner.

On the subject of chain tensioners, the standard Brompton plastic one is a bit fugly, so I'd been thinking of getting one of these, made by Bikefun in Taiwan:

http://blog.yimg.com/2/9Met_Fp7s5._MPkWTZM8yTQwNm_WQs5FK5dV9aLDl7NiJb.7cJqIPw--/27/l/C6eN14NNodWkBSj0QPlKHQ.jpg

The only problem is that they only appear to sell them on Ruten, the Taiwanese eBay equivalent, and it seems that you can't use Ruken if you're not Taiwanese. So getting hold of one would involve a local shipping agent, and therefore a lot of faff. Well, some, anyway. Enough for me to be distracted by other things. In the meantime, Brompfication released their own aluminium chain tensioner, so I got that instead:

http://www.zen118609.zen.co.uk/SuperBrompton/chainten1.jpg

It's lighter than the Bikefun version, but still heavier than the standard Brompton part. The standard Brompton part weighs 129g, with jockey wheels, spring and all fittings:

http://www.zen118609.zen.co.uk/SuperBrompton/chainten2.JPG

The Brompfication part, with Hope jockey wheels and all titanium bolts weighs in at 174 grams.

http://www.zen118609.zen.co.uk/SuperBrompton/chainten3.JPG

The aluminium chain guide ring is the standard Brompton part, and does let the side down a bit. I hadn't been able to find anyone who made a better one, although I've now discovered that there is an aftermarket one:

http://blog.yimg.com/2/9Met_Fp7s5._MPkWTZM8yTQwNm_WQs5FK5dV9aLDl7NiJb.7cJqIPw--/88/l/VYlOeiH2QFpVK4xs6.6w7w.jpg

Trouble is, it's made by Bikefun...

Another problem is that with the 11t Hope jocket wheels and the 15t sprocket on the SA hub, there's negative clearance between the two.

http://www.zen118609.zen.co.uk/SuperBrompton/chainten4.JPG

I need to try it with the original 10t jockey wheels to see if that gives enough clearance. If not, I may have to switch to a 14t jockey wheel. I think a trip to Condor may be in order to have a gander at their Bromptons and see how much clearance the standard models have between the sprocket and the jockey wheels.

Here it is in all its glory:

This is a fantastic build.

I'm late to this thread - Google brought me here because I want to put an ultratorque chainset on my brommie. I'm not sure I'll be able to do it quite as elegantly as you, but wanted to check whether there had been any issues with the chainline / other dimensions with a 52t ring on the inside.

Have you tried folding the rear triangle? I'm currently running a vintage DuraAce setup which required minor surgery (machining off the inner studs and fitting the ring on the outside) to avoid fouling the rear triangle during folding (fitted fine except for that).

Thanks

Chris

Yes, I've folded and unfolded the bike lots of times now - it gets unfolded when I'm working on it, and then folded away when I'm not. The chainline seems fine so far. I haven't fitted the chain yet, but the inner chainring is right hard against the rear triangle (which is where it needs to be) so I don't see any problems there. The only difference really is that the chainguard presses rather more firmly against the stay for the front mudguard than it does on the standard set up, so if you try to spin the pedals when the bike's folded there's much more resistance. Hardly a deal breaker though.

Fab. Thanks very much for the reply. Keep the updates coming, please!

Chris

Yes, I've folded and unfolded the bike lots of times now - it gets unfolded when I'm working on it, and then folded away when I'm not. The chainline seems fine so far. I haven't fitted the chain yet, but the inner chainring is right hard against the rear triangle (which is where it needs to be) so I don't see any problems there. The only difference really is that the chainguard presses rather more firmly against the stay for the front mudguard than it does on the standard set up, so if you try to spin the pedals when the bike's folded there's much more resistance. Hardly a deal breaker though.

Hi,

this is an very interesting and informative thread. I allready learned a lot for tuning my own Brompton. Looking forward to your next steps.

Did you see that Oneseven Carbon has a carbon chain guide ring?

Mat

I need to try it with the original 10t jockey wheels to see if that gives enough clearance. If not, I may have to switch to a 14t jockey wheel. I think a trip to Condor may be in order to have a gander at their Bromptons and see how much clearance the standard models have between the sprocket and the jockey wheels.

the other problem is that the brompton jockey wheels on a 2 speed slide with the chainline. not so much of a problem for you but they can't just be swapped out for even another 10T.

if you wanna sell one of your hope 11T jockey wheels, let me know, I guess it'll still fit on the lower position on the tensioner so we could use one each

.

Report it and it'll go away.

^^^^ I hadn't, but I have now. Guess it's time to order some more carbon from Hong Kong. Thanks for the heads up.

^^^ Sliding jockey wheels aren't a problem for me, as this Brompton has a 5 speed rear hub and so doesn't use the Brompton derailleur. I think it's better using two 10t jockey wheels, as the clearance between them is pretty minimal. I've got plans for the Hope jockey wheels - I reckon they'd go rather well with a Force rear mech.

customspiration

http://www.ebay.co.uk/itm/Brompton-/171137007571?ViewItem=&clk_rvr_id=576958031275&item=171137007571&nma=true&si=Py6SYomw5E2lJwDwNCQQn9dsWF0%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

drill

I rather like the internal cabling idea - that's rather fine. As and when I have to get the lacquer redone on the main frame I might think about that.

But DIY drilled brake levers? Nooooooo thank you!