Custom build folder touring bike with Rohloff hub...
 

I hope to have Keith and Arvon build me a folding touring bike with 20" wheels and trimmings for use in sustained touring.

I was leaning to the new Shimano 11 speed IGH, but now issues have cropped up with that hub :notamused:, and I am now looking at the 14-speed Rohloff. For 20" wheels Rohloff recommends a 13-tooth sprocket. If push-comes-to pull I can always go back to a Shimano 9 speed rear, 3 ring front, and ... forget the IGH idea

What front chainring should I use with the 13 sprocket and Rohloff? What dropout should I use for the Rohloff as it is up in the air/on the table now as far as choices are right now. Other suggestions are solicited/ asked for.

Remember this folder is being built from scratch and is to be airline friendly and for sustained touring, but is for a 100 kg fellow that stands at 195 cm. I already have an Arvon-built expedition grade bike bike (on the S&S website), and this folder should be more airline friendly and with the Rohloff should be able to use a BOB ibex and or Panniers.

Am I dreaming or should I drink more Chateau Neuf de.. and re-think this whole idea and use a BMW R750 :p

Serious input needed as I am really scratching my head. Keith and Arvon are willing to listen and to build. I really trust Arvon's ideas :thumb:

I don’t know much about the Rolloff hub. It didn’t exist when I built my folding bike 30 yrs. ago. Being an average size guy of 115 kg. and 188 cm tall, when I built it I used tubing left over from projects to build a tandem and a triple. I used derailleurs and BMX caliper brakes. Those brakes never did work well, so they quickly got changed for cantis. I have made several rebuilds/upgrades over the years and currently have a 12-32 8 spd. Cluster with 60-50-28 rings on an old Shimano Deore XT crankset with 20” wheels. My most recent upgrade is new wheels with a cluster to replace the freewheels that are no longer available. I Deore XT hubs and Velocity rims. It has been cold enough that I haven’t ridden it this year and have been riding other bikes.

My bike has 38 16 and 26", 1.5" wheels, so you could do the math from that. As you know, the Sheldon IGH calculator allows you to run all these numbers. So you can open one window and enter your current Arvon gearing, and then open a second window and enter your projected Rohloff. In most cases you are going to have to take a haircut on the top or lower range. You can open another window for the target bike, like say a Thorn (I think it would be 38, 16, 26", 2" tires. So have a look and figure out what part of these ranges works for you.

Have you held a Rohloff rear wheel assembly. It's like holding a cannonball. I'm not sure it makes sense unless you are looking at a lot of dirt. And in that situation I would question 20 inch wheels. I can see 20" wheels on a folder, though I would just go with a Bike Friday, or even Brompton. Folder's aren't all that easy to one-off. With relatively minor changes it ought to be possible to make a 26" bike that fits a box a lot better than your Arvon. So there are lot of options, not to say the original one isn't a go.

My Arvon-built expedition grade bike has 26" wheels with 48 spokes and 4X lacing. With S&S connectors it just fits into 2 big suitcases. The bike was built for my stature: 6'5" and about 110 kg. It weighs 40 lbs as-it stands in my home. Man alive, is it ever strong - but with strength comes some extra weight - that is why I consider it to be an expedition grade bike not just a touring bike. Every LBS that I have taken it to has commented on Arvon's robust design and attention to details - and of course how strong the wheels are - and it's weight. :thumb:

Now, I want something more compact and lighter - hence the folder-mini-velo idea with 20" wheels (that are quite strong) and an IGH. The Rohloff is quite light as compared to the cannon balls I have held, and more smoothly finished, but less aerodynamic :p

I purchased a Brompton for my son a year ago and it is great for the city, but not for touring. No way is it robust enough. Plus, it wasn't designed for easy part replacement outside of the UK. When a crank arm broke, he had to wait a while for a part. The Rohloff is in a different robustness category..

I want to carry 1 bag now, not 2 suitcases. That is not to say the Arvon-built has no place - it certainly does. However, with the kind of travels I am looking at in the near future I want one bag - and preferrably similar to the S&S soft case with shoulder straps :thumb:

Makes sense to me, and more importantly, to you. Based on that I would wonder about the Rohloff. My rear wheel weighs like some people's bikes. I wonder whether some wide range rear sprocket, a 9 speed, would get er done. I remember when a 5 speed touring bike was fairly common. Anyway, it will be interesting to see what you come up with, please post photos.

There is a back story to al of this...

Last summer I set out to modify my Phillip's 20 folder which had been running as a drop bar fixed gear into a fully geared touring bicycle... it is still a work in progress and the bike has served as a test bed for many ideas and it has been subjected to some rather extensive modifications and will see a few more.

http://www.ravingbikefiend.com/bikep...rest21side.JPG

I have a 50 km ride to work which takes me to Arvon Cycles and Arvon was intrigued with the idea of my riding a bike with 20 inch wheels 100 km a day, taking it out for 200km weekend rides and knocking down 7 hour centuries with a nearly full load of gear.

I did a lot of late night modifications at the shop to add brake bosses and cable guides and turn what started the season out as a fixed gear bike into a 21 speed (13-28 block with a half step triple) and one of the future mods is to upgrade to an 8 speed cassette wheel to bump up my top gear just a little as this will allow for an 11 tooth cog.

Because of health issues I was okay with a 75 gear inch high on a tourer as I have great aerobic capacity and can spin at 90-100 rpm all day while cranking those taller gears really aggravates a lower back injury... a few more gear inches will be nice as when it is just me and the bike with no gear it really wants to fly and will make 50kmh sprints a little easier as my current gearing and ability to spin limits me to around 45kmh.

It is surprisingly easy to spin these rather light wheels up to very high speed... the new gearing set up will give me a 17-89 gear inch range with an 11-30 8 speed cassette which should handle everything except serious racing and I have plans to build another compact racing bike for that.

Anyways... I think Arvon was initially amused when I first rode the folder in and then got more interested as I related how nice a ride it was, how stable it was, and even he was impressed with how many miles I was knocking down.

He has also seen a lot of people touring on Bike Fridays.

I almost never fold this bike but the hinge does allow me to break the bike in half pretty quickly and got to thinking what it would be like if this bike had an S&S couper instead of a hinge and then... started wondering what it would be like if we built a new S&S coupled compact tourer on a 20 inch wheeled platform that would fit into a standard or even a slightly smaller airline case.

I threw the idea out here and quite a few folks were intrigued and now we are going to set to work building a new touring bike that will run on 20 inch wheels and it will probably be running a Rohloff hub... I was initially interested in the Shimano 11 but the reviews have not inspired confidence.

On the Rohloff gearing and a 20 inch wheel...

A 50:14 ratio on a Rohloff hub in a 20 inch wheel with 1.5 tyres gives a gearing of 18.6-97.9 gear inches which is pretty close to perfect for a long distance touring bike, the 14 tooth cog is reversible, and a bigger chain ring will extend drive train life.

I have been using bikecad to develop build ideas and initially was looking at double tube diamond frame but it appears that building a monotube design with an S&S coupler is more than feasible if the frame is designed right and uses the right materials.

The coupler should allow us to build a small wheeled tourer with an extended wheelbase which will also improve stability, ride quality, and cargo carrying ability.

S&S coupled 20 incher monotube. I see two problems:

1) Normally the S&S is in a parallel type application where the loads are tension or compression, not to say what you have in mind won't work. Ok I just checked their site to see what the largest one they made is, and found this instead:

http://sandsmachine.com/#monotube%20frames

Maybe this:

http://www.bikerevuk.com/bikepics/tike/tike.htm

2) Just how big a wrench would a person have to carry to snug the S&S on a monotube size tube.

One thing I have always wanted to try was that system they used on the old french bikes where the shifter was under the seat. Not maybe all that convenient, but it does eliminate some clutter. Kinda a touring bike Suicide Shifter. :)

..the monotube on my Greenspeed GTO has a S&S, which is probably the largest one that S&S makes. The wrench is the same size as the S&S wrench for my Arvon-built diamond tube. Wrench size is a red-herring IMHO :p

This is the kind of stuff that keeps me up at night... :)

We are not seeing a problem with a single coupler on a monotube as it has been done successfully by other builders and with an upright our options to provide extra bracing are there.

Oddly enough... if you look at my 20 the doubled brace behind and below the joint does not provide support and some versions of this bicycle do not have it. That folding joint is strong enough to support riders who weigh several hundred pounds and they are rock solid.

We will also look at non S&S couplers for this reason.

Where is the coupler on the GTO? Is it on the boom for the pedals. That wouldn't worry me. Even if it was on the tube between the wheels, riding that seat down from worm height wouldn't probably hurt anyone either. The monotube on an upright is a whole other thing. Anyway, take it up with S&S, they are the ones who say it isn't safe.

Sixty Fiver,

Your Phillips 20 looks identical to my Raleigh 20. Mine dates from the '60s. I used it as a general inspiration for the homebuilt folder I built in 1982. Later my aunt gave the Raleigh to me and I modified it like you did for my wife. It how has cantis and a descent crankset with derailleurs. The person who actually rides it the most is my wife's sister when she comes for a visit.

Here's another idea you might not have seen:

http://www.rodbikes.com/catalog/6-pack.gif

Check out http://www.rodcycle.com/ and look for their 6-Pack Micro Folder.

That thing must be tiny when folded. If nothing else, this has to be S&S favorite bike ever

I like that. It's about 1800 dollars of S&S, but it looks like a good cause. Some weight to those couplers also.

Was drawing up a diamond framed model as well... that is a lot of couplers.

The Phillip's 20 is very similar to the R20 save for a few small details and was built by Raleigh... it uses a different fork, was fitted with a 3/32 chainwheel and has a standard 73mm bottom bracket shell with Raleigh threading.

The ones on the back are hard to see as any better than the bolt arrangement on the BF, though maybe it is classier. :) Two of the ones up front just make it more compact which might not be everyone's cup of tea.

Here are some photos of the bare frame assembled and disassembled.

http://bikeforums.net/attachment.php...hmentid=195349http://bikeforums.net/attachment.php...hmentid=195350

second photo seems to be missing some parts. Just my luck I'd forget the seat stays at home.

Aw, come on. The framebuilder wasn't stupid:

http://bikeforums.net/attachment.php...hmentid=195395

Nice. Probably the most compact I have seen, and these days you can't do enough to make those airlines feel good. one could do that whole build without the S&S if one was on a budget, but it is a lot of bling on the right build.

One thing I am a little curious about is why they oriented the cut-outs as they did. Normally the points are on the vertical axis. If they are just under tension and compression it's one thing, but as close as they are to the ends, I wonder. Looks nice.

6 couplings would be a natural for Arvon, he is used to big numbers with his tandems.