Folding Bikes - What's a light steel bike?

Just out of curiousity, seeing as I now own a Downtube Mini, what's a lightweight (sub- 11kg) steel folding bike? I'd be interested to know about a small-folding hub gear bike to drool over. Must be steel, tho.

Brompton?

Brompton?

Jep, but if hub gears is a must then only with a little ti at the front and rear.

A steel bike can be as light as an aluminum one.

A steel bike can be as light as an aluminum one.

Yes, when tubes are concerned but a folder?
I thinks what adds to the weight most in a folderframe are the massive hinges - they must be of the same material as the tubes, right? I take it that steel hinges are in overall heavier than alu ones for a given needed stability.

I'm sure steel bikes *can* be as light as aluminium ones, but when I was bike hunting all I found was aluminium. Maybe it's the price bracket I was limited to. I guess my question is really about whether any folding bikes make use of high-strength steels that can be lightweight but at the same time really strong. What, for example, would be a 7, 8 or 9 kg steel folding bike that costs less than a Brompton new?

so it has to be steel

and it has to have a can ( internal gears)

and light 15 16 17 lbs

and strong ( I assume over the 230 lbs limit of some manufacturers )

and cheap ................


Thor

What you are looking for does not exist at a lower price than the Brompton.

Would you settle for some steel parts on a titanium bike, for about ten times the price of a Brompton?
You would have your weight and strength.

ufbusa.com

Would the Bike Friday Seasons Tikit work here if you replaced some of the parts with Titanium?

--sam

tikit is close to 30 lbs last time I checked.... I might be wrong .though

we want half of that with a can ....

lol

Tikit is around $26 pounds. Ti seat post and other Ti bits and bobs might reduce a pound or two. But definitely not possible with just steel.

I suppose you could also mod a Dahon Boardwalk with a hub.

But if you want a bike without modding, Brompton is the best game in town as far as steel bikes go.

so it has to be steel

and it has to have a can ( internal gears)

and light 15 16 17 lbs

and strong ( I assume over the 230 lbs limit of some manufacturers )

and cheap ................


Thor

Not gonna happen, is it?

Maybe you can find a bike with 3 out of the 5 criteria. Not 5/5.

Tikit is around $26 pounds. Ti seat post and other Ti bits and bobs might reduce a pound or two. But definitely not possible with just steel.

I suppose you could also mod a Dahon Boardwalk with a hub.

But if you want a bike without modding, Brompton is the best game in town as far as steel bikes go.

The best game, perhaps dont know but still not that was was to be hit:
pure steel, 7kg (15 lbs) - 9kg (19 lbs) with hubgear

The lightest off the shell all steel brommi with hubgears (3speed, no fenders, no lights) is 11.5kg (25 lbs). Get some lighter rims (alu :D ), lighter tires, lighter tubes, you have it, a few grams sub 11kg.
Want it lighter still? Get some really expensive (and no steel) modifications like ti spokes, ti-bottombracket, king headset etc.

Hmm... it's not going to happen any time soon, I gather. What if it doesn't have to be cheap?

I hope you folks don't mind the theoreticals - I'm really mainly interested because I work in the steel industry and I hear a lot about new high-strength steels... but obviously they're being used in other applications than folding bikes!

If you had a new high strength steal that was light compared to the stuff currently being used, you could do what Len Rubin did when he created the Ultimate Folding Bike out of Titanium. Just fab your own bike following a design you really like (Brompton, for example) with the material you want to use.

Well... you said it didn't have to be cheap. ;)

Just out of curiousity, seeing as I now own a Downtube Mini, what's a lightweight (sub- 11kg) steel folding bike? I'd be interested to know about a small-folding hub gear bike to drool over. Must be steel, tho.

11kg is 24lbs.

One Way Tikit is 19.1lbs (8.7kg) minus saddle and pedals. Most wide-range internal hubs are around 4lbs, but the Sturmey Archer is about 1kg. The stock rear hub on the one way Tikit weighs 282 grams, so we have a net increase of (1000-282 = 718 grams). So we're at 9.4 kg total, leaving you 1.6 kg for saddle and pedals. With that we can easily fit some nice removable MKS pedals and most saddles of your choice and still stay under 11kg.

Do some basic component swaps (trading the heavy stock cranks, bottom bracket, seatpost and stem for lighter ones) and you could easily get the weight down to allow you to fit a 4lb/2kg internal hub such as a Shimano Alfine or SRAM S7 or i9.

The SA 8sp hub is 1.5kg, or do you mean another version?

The SA 8sp hub is 1.5kg, or do you mean another version?

Probably the 3spd freewheel which is 1020gr ;-)

BF Pocket Rocket Pros range from 18-21 lbs (and $1500-$4500 on the other end); if you ordered on with a hub gear (maybe even an 8 sp gear), you could probably meet your criteria.

I would not describe this as either cost effective or the best use of a PR Pro - but there it is.