Just about on the road – Recumbent Brompton Project 2

Whooeee! It all seems to work.

Yellow Brecki 1st day 15

Having overhauled my old red 2003 Brompton and re-installed the Juliane Neuss recumbent kit, with a single chain drive to replace the old belt and chain setup, I’ve ridden it round the block and it all seems to work. Some detail work to do yet to get it running smoothly and make it fold properly but I think I’ve crossed the big hurdle of getting a chain drive to work.

The overhaul started with stripping the bike down to treat the rust patches with Kurust then paint with Hammerite Gloss in a cheerful yellow colour. The paint isn’t perfection but it’s pretty good for a backyard aerosol job, Hammerite gloss paint is very forgiving.

Then I refurbished the rear hinge which had seized up (having been previously worn and wobbly), cleaned up and lubricated everything else, removed all the gubbins associated with the belt drive and moved the mountain drive to the boom.

The scary bit was fitting a long chain. Would the Brompton Derailleur cope with it? Would my plan to use chain tubes to route the chain and allow it to fold work? A great deal to go wrong.

The bare chain was never going to work as the bottom section clashes with the front wheel but installing some chain tubes on a lash-up basis dealt with that and some fine tuning of the way the tubes were fastened to each other and the frame led to an installation that seemed to run OK on the maintenance stand.

Yellow Brecki 1st day 8

That wire thingy on the upper chain tube came with the tube but I’ve ordered a more sophisticated “floating tube” gadget

Here’s the front end

Yellow Brecki 1st day 9

And here’s some real magic. Having taken the bike off the stand, without thinking, I flipped the rear wheel under into the parked position

P1080063

Could have been a disaster, I wasn’t paying attention at all, but see how the chain tubes keep everything under control. I need to make that top one splittable (we do that on our Hase Pino, it’s not rocket science) and I think I should be able to fold and unfold the chain and keep it all taut enough. I’ll probably make the bottom tube a long split one as well.

A few other details, here’s a clamp with a piece of stud used to hold the Mountain Drive torque arm steady. Thanks to Simon Koorn for suggesting how to do that.

Yellow Brecki 1st day 4

Those pedals are some cheap folding pedals but I’ll probably fit a Brompton folding pedal on the left and a cage pedal on the right.

For anybody not familiar with the Juliane Neuss design, here’s how the boom mounts on the head tube.

Yellow Brecki 1st day 5

 

I need to work on the gears, there’s an occasional skip which is probably due to fitting a new chain to worn sprockets, but I’d bought some new sprockets precisely for that purpose. It’s set up with SRAM narrow range 6-speed which goes well with the Mountain Drive to give 12 equally spaced gears.

However I have a spare Brompton Wide Range (BWR)  hub and I’m probably going to fit that instead, when I first tried out the recumbent I felt it needed higher top gears as the steering is a bit twitchy and pedalling at a high cadence at speed was quite scary. On gentle downhills it gets up speed very fast so I want to take advantage of that. But I’ll leave it with the narrow range setup until I get used to it and everything working, the BWR requires a new set of learning to sort out the overlapping ratios between upper and lower range on the Mountain Dive.

Also for some reason the brakes are really not working well, I’ve got used to really good brakes on my newer Brompton, I think the front caliper on this one is the same as the current ones so I’ll experiment with better pads. I have some Swiss Stop Greens in the drawer and they are supposed to be excellent.

And you’ll see it has Kojaks, my first set. Well it is a bike for racing and I won’t be using it much for urban utility cycling.

So now I have two weeks to do the fine tuning and get my recumbent reflexes working, at the moment steering a straight line is not really working, especially at lower speeds. “Abeillaud”, a member of the french speaking Brompton Forum, has organised a recumbent team for the Brompton World Championships and Juliane herself will be riding with us so I need to make a decent job of it.

 

Advertisements

Tags: ,

8 Responses to “Just about on the road – Recumbent Brompton Project 2”

  1. sa101fall2012 Says:

    Wow, gorgeous work!

    How is it riding and what is the foldability like?

  2. chrisrust Says:

    I’ve used it for a three day, 150 mile tour last summer and it’s very comfortable, no pain! Even with the “hard” foam seat. It takes about 60 seconds to fold, including putting a strap round to keep it all together and although it’s bigger than a normal Brompton I’ve taken it on several trains with no difficulty. However there’s some clear lateral flex in the boom+frame when the pedalling force is high, especially with the Mountain drive in low ratio which really multiplies the force in the chain. That’s led me to decide that it’s probably never going to be a serious touring bike, despite the transportability.

  3. sa101fall2012 Says:

    Thanks for your remarks, Chris— greatly valued all of your insight into the Brompton world for years.

    My main bike is a recumbent, but I take a Brompton when I travel. I’m 6′ 1″ with some wrist problems (thus the recumbent) and I still haven’t figured out how to get the B dialed in just right. I’ve got the standard handlebars and perhaps if I got higher ones (H type) that would help, but then I think there are issues with re-wiring the brakes and gear cables.

    I’d love to see a chart or some helpful Brompton-specific guidelines for adjusting things ergonomically. Some while back you had some good suggestions especially for shorter folks, and I learned some things (about adjusting the seat back and forward, etc).

  4. chrisrust Says:

    If you haven’t used Ergon Grips they are very worth trying, lots of people say they help with wrist problems and that includes me. I found the combination of ergons with the more springy M-bars more or less eliminated wrist problems I had been having on my previous bike with straight bars, even on quite long rides.

  5. chrisrust Says:

    What kind of Recumbent do you have? I’m considering an HP Velotechnic Grasshopper, great reviews as a touring bike and it folds up (a bit) for travel.

  6. sa101fall2012 Says:

    I did get the Ergon grips and love them. So, the M-bars are more springy than the H and this is better on the wrist? I don’t actually know much about bikes so my attempts at better ergonomics are kinda shooting in the dark. I suspect that most of the ergonomic bicycle people are looking for different situations (DF bikes), but perhaps their knowledge would work just fine for a Brompton. I would like to be as upright as I can, I believe.

    I have a Burley Canto, which I adjusted to a short wheel base. It is quite upright and very comfortable, but also a heavy bike, about 34 pounds. I like it quite a lot, but am now looking into something lighter and faster. The Grasshopper looks pretty interesting, but as my neck is also dicey, I’m wondering about the seat with the recline and keeping one’s neck upright….

    I’m curious if the Grasshopper can fit into standard airline luggage. Do you know?

  7. chrisrust Says:

    H-bars and M-bars use the same aluminium handlebars (different stem) so they should be similar for your wrists but the higher position may well be a big help. I had a problem with our Hase Pino (see here) and higher/closer bars was one of the answers. There’s a lot to be said for just taking an intelligent oversight of your own comfort, for example sit in a variety of chairs and spend a minute or two thinking about the angle and height the backrest, you’ll soon learn to spot which will be comfortable for more than 5 minutes and what makes the difference.

    The Grasshopper would not go in airline standard size luggage, if you have a look at the photographs on the HP Velotechnik website you’ll see it’s not a very ambitious fold but it would certainly mean it’s easier to take onto a train or into a car. Having packed our tandem for flying it should be a reasonable proposition in a box with some padding, the trick is to choose your airline and many US airlines seem to be unreasonably hostile to bikes whereas elsewhere you can often get your bike on for free or a small charge. (they bend over backwards for golf clubs and skis probably because airline managers and their friends play golf and go skiing but cyclists are dangerous communist perverts who would prefer to ride there than buy tickets)

    The weight is around 16.5kg which is similar to your Burley (not sure what a true all-up weight would be, some manufacturers give a realistic weight and some give a minimum weight). There are some very lightweight recumbents but they tend to be fairly uncompromising and expensive, I’m not happy that the Grasshopper weighs so much but I’m beginning to see that all the well-established touring bikes weigh similar amounts and it has a great reputation for rideability and comfort, I’m hoping to test one soon.

  8. Michael Hathaway Says:

    Good point about the concessions to golf clubs and such, while there is also a kind of hostility to bikes with airlines. Would be nice to have a wiki on using bikes with public transit (which trains, subways, buses, etc allow bikes at all times, or only non-rush hour; airline policies, etc)

    I will try some of the higher bars (or at least ride a Brompton with higher bars)— it’s been tricky sometimes figuring out what is comfortable or not when there is too much choice in handlebars and everything is related in complex ways.

    Let us know if you try the Grasshopper— curious about the weight and if it’s easy to push or pull at a train station, for instance.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


%d bloggers like this: