Latest version of the lightest folding steel bike

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jahknob
Posts: 61
Joined: Tue Sep 07, 2004 1:27 pm
Location: London, UK

by jahknob

It was a close-run thing the day before the event, but we managed to finish the rebuild of my ULT "backpack" ultralight Steel Roberts bike (though not quite rideable yet - some tweaking still to do). It's now tipping the scales at a little under 4.7kg (though this is the "show" build - I wouldn't ride those track tubbies on the road - it'll be close to 5kg "ready to ride").

There's a show report about Bespoked Bristol (the 2012 UK handmade bicycle show) with some pics here:

http://road.cc/content/news/55537-bespoked-bristol-roberts-pegoretti-foffa-kurtz-quoc-pham-velobici-lots-pics

The reporter seems to like the front hub (have got other good stuff from B-T-P on there too) , but we threw on an Experimental Prototype carbon cassette that arrived just in time that didn't even get a mention. What an outrageous piece of work that is! (see other threads here for info) - and cheaper than some of the Ti/Al cassettes out there...

I'll get some other pics once I get the bike back and can sort it out. If anyone wants to see the spec sheet, I will post that here. May even get to ride the bike later this year (fitness permitting!), and will report further.

j.

ajz07
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Joined: Fri Jul 15, 2011 9:32 pm

by ajz07

looks absolutely amazing

by Weenie


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bikewithnoname
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Joined: Tue Sep 22, 2009 1:29 pm
Location: Paris

by bikewithnoname

nice! what's the frame weight?
"We live in an age when unnecessary things are our only necessities." Oscar Wilde

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stephen@fibre-lyte
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by stephen@fibre-lyte

Blimey, I've never even heard of Bespoke Bristol. I guess that it's not overly publicised. Shame, I would have like to have gone.

Nice bike by the way. I'm surprised that you didn't just call up north for the carbon chainring and cassette :wink: Bear in mind that the cassette probably won't be very durable, we've done a few in our time. I haven't seen Mattias carbon parts up close, but I'm guessing that it's water jet cut prepreg carbon sheet. Mattias?

KLabs
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by KLabs

specs please :-)

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prendrefeu
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by prendrefeu

Looks great!

But, just for clarity - it isn't quite folding, it's more like "halving" no? I mean, the S&S couplers split the frame in two, the frame itself does not "fold"

Rob English has an ultra-light steel folding bike that he has made, and it's fully steel (stays, tubes) minus the carbon fork.
Exp001 || Other projects in the works.

bones
Posts: 422
Joined: Sun Aug 23, 2009 10:38 am

by bones

jahknob wrote:It was a close-run thing the day before the event, but we managed to finish the rebuild of my ULT "backpack" ultralight Steel Roberts bike (though not quite rideable yet - some tweaking still to do). It's now tipping the scales at a little under 4.7kg (though this is the "show" build - I wouldn't ride those track tubbies on the road - it'll be close to 5kg "ready to ride").

There's a show report about Bespoked Bristol (the 2012 UK handmade bicycle show) with some pics here:

http://road.cc/content/news/55537-bespoked-bristol-roberts-pegoretti-foffa-kurtz-quoc-pham-velobici-lots-pics

The reporter seems to like the front hub (have got other good stuff from B-T-P on there too) , but we threw on an Experimental Prototype carbon cassette that arrived just in time that didn't even get a mention. What an outrageous piece of work that is! (see other threads here for info) - and cheaper than some of the Ti/Al cassettes out there...

I'll get some other pics once I get the bike back and can sort it out. If anyone wants to see the spec sheet, I will post that here. May even get to ride the bike later this year (fitness permitting!), and will report further.

j.





S&S coupled bikes are not the same thing as a folding bike.

jahknob
Posts: 61
Joined: Tue Sep 07, 2004 1:27 pm
Location: London, UK

by jahknob

Well,

I'm not going to split hairs. Strictly speaking it isn't a folding bike, it splits in to two halves and can be packed into a suitcase. It's not a Brompton or a Dahon or similar folding bike - you can't go from riding to folded down in seconds flat. But you can travel with it and pack it into a suitcase which will incur no additional luggage/oversize fees (and fold up the bag and carry it away like a backpack - with all of your other accessories and packing materials inside).

The English concept is a beauty - but I don't think it has any advantages over the S&S couplings in terms of what you can do and how fast you can do it (and the couplings are probably a much cheaper option and more versatile).

Does anyone know of a lighter steel road bike (folding/splitting or not)? If it didn't have the S&S couplings, I believe we could have saved an extra 200g or so on the frame, making it under 1400g.

And, just to pre-empt any comments about the spec sheet that I'll post - the bike is in "show" mode. When I ride it, I use standard tubulars and steel/Ti/alloy drivetrain for longevity, so it comes in around 11lbs on the road.

j.

PS If anyone has any hints on how to format the specs a bit more clearly, please pm me!
Last edited by jahknob on Wed Mar 28, 2012 2:31 am, edited 1 time in total.

jahknob
Posts: 61
Joined: Tue Sep 07, 2004 1:27 pm
Location: London, UK

by jahknob

Part / Make + Model / Wt(g)
Frame (F&R) Roberts Columbus Foco, Dedacciai Blacktail, inc. S&S BTCs 1579
Fork THM Scapula SP Tuned 1.125" (182mm steerer) 231
Headset Cane Creek AER 1.125” 47
Top cap & bolt AX Lightness 6
Spacer 5mm carbon 1.125" 2
Seatpost collar BTP Carbon 7
Stem Carbonschmiede 97mm -7 degrees, 26,0mm 58
Handlebar Schmolke Carbon TLO Modolo-bend (42cm ctr-ctr) 142
Seatpost Schmolke in-line TLO 300mm 92
Saddle AX Lightness Phoenix 53
Crank/BB axle THM Scapula (LH 123g/RH & axle 157g) 280
Bearings/cups THM Scapula (27.5g per steel bearing) 55
Chainrings Dark Albert Carbon 50/36 (39/15g) 54
Chainring bolts AX Lightness aluminium 8
Brake/Shifters 2010 SRAM Red, BTP hoods & clamps (216+25+9) 250
Brakes AX Lightness 3000 49g + pads/bolts 21g + misc. fixings 10g 80
Brake cables Alligator iLinks/PowerCordz 32
Rear derailleur SRAM Red tuned w/Dark Albert carbon cage/pulley wheels 112
Front derailleur Campagnolo Record compact 10 Carbon (BTP tuned) 58
Derailleur cables Alligator mini i-Links/Powercordz 28
Pedals Aerolite Ti 70
Chain Yaban 10S Ti 106 links 218
Cogs/lockring Hellore Experimental Prototype Carbon 10s 11-23 68
Front hub BTP Carbon 50
Rear hub Tune Mag 140 145
Rims (2) Reynolds KOM (20/24h) 450
Spokes/nipples Sapim CX-Ray & DT Al 204
Tubulars (2) Tufo Elite 110g 224
QRs (2) Tune Skyline Road 18
Bar tape BBB Pro Light tape (black) 33g + plugs 2g 35
Tub tape Jantex 22
Bottle cages (2) BTP Kevlar & bolts 12
Total (g) 4690

bikewithnoname
Posts: 1734
Joined: Tue Sep 22, 2009 1:29 pm
Location: Paris

by bikewithnoname

To say that is a nice build is a gross understatement! :thumbup:

Top work :beerchug:

( I wouldn't ride those TUFO tubs on any road mind you...)
"We live in an age when unnecessary things are our only necessities." Oscar Wilde

bones
Posts: 422
Joined: Sun Aug 23, 2009 10:38 am

by bones

Yeah, but it still isn't a folding bike. S&S coupled bikes are definitely not the same thing as a folding bike. It's not a splitting hairs thing. It's a big difference.

by Weenie


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