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For every day use and for touring, we prefer the simplicity, ruggedness and ease of maintenance of V brakes. We even prefer the “feel” of top quality V brakes. We have rims available, with a tungsten carbide braking surface, which provides fantastic braking combined with exceptional longevity.
People say that it’s about time that bikes caught up with cars and motorcycles , which all now use disc brakes. There’s no doubting the improvements to braking performance that disc brakes have made to all forms of motorised transport. However these vehicles have moved from drum brakes to disc brakes. Bicycles have been using disc brakes for more than 100 years. Bike rims are disc rotors - but instead of having large 550+mm aluminium discs, bikes are now being offered with 160mm stainless steel discs. There’s no doubt that hydraulic disc brakes are preferable to V brakes in the deep, muddy conditions often found in UK mountainbiking. They are, however, more easily damaged (especially in transit) and a bent rotor is much more difficult to straighten than an “out of true” wheel. Indeed, if the rotor is warped enough, the wheel won’t even turn! Don’t compare the 8 to 10mm thick, cast rotors, found on modern cars and motorcycles, with the 2mm thick, stainless steel plate, rotors found on bicycles. Our bikes use raked fork blades, these are exceptionally comfortable, they will withstand the forces of cycling (and have done so for generations) but raked forks will not withstand the forces generated by a disc brake, which are very different to the forces generated by V brakes, even at the same rate of retardation. In recent tests on a 1Km long 25% gradient, I determined to my satisfaction that a well set up V brake will stop a loaded tandem from speed more positively than a 203mm disc brake. This is not the whole story though - clearly there is rim wear Vs rotor wear to consider. We’ve been advocating using 3 brakes on a tandem for 30 years and we’ve been selling tandems with 2 V brakes and a supplementary rear disc for over a decade.
I have bowed to pressure and introduced the option of a tandem disc fork. This is very heavy duty and 135mm wide, so that there’s no dish in the front wheel, it will stand up to the forces involved but it’s significantly less comfortable than our twin-plate crown V brake fork. So you can have a Thorn tandem with 2 disc brakes but I recommend that you don’t have it! It may seem odd to take the trouble to make the best possible disc fork and then try to persuade customers not to buy it - but that’s us! I made the disc fork for 2 reasons, firstly, I’m sure that some people thought that the advice was given because we couldn’t supply a disc fork - well we can and the advice is still the same! The second reason is that some customers have said that they’d like a 650B tandem and others want to run 700c. Well they could now if they wish but only by having 2 disc brakes. Perhaps it may make sense to some customers to have one of our sturdy frames and bomb-proof Rohloff hub built as a sporty, high performance 700c machine? -
We can now fit a 203mm front disc brake to one of our tandems - but please read the following warning.
When I originally designed the Raven Twin, I had to choose either a comfortable fork, with provision for V brakes, or a fork which would withstand the considerable (and very different) forces created by a disc - I choose the comfortable fork! To make a fork suitable for tandem use, with a 203mm disc front brake, would’ve required an exceptionally beefy fork. I knew how uncomfortable such a fork would be from our 1999 tandem tour in Australia, I hope I never have to endure such discomfort again!
I certainly didn’t wish to produce a bike with forks, which were even less comfortable!
I’ve no worries about our Raven Twin fork, when we hit a cattle grid at 50mph, on our Raven Twin! Yet, when I put an ISO disc mount on a pair of forks, with identical blades, I managed to write them off, on an unloaded solo bike - was I behaving like an idiot? No, I was simply simulating an emergency stop, from 10mph and I was only using a 160mm front brake! Even the most careful and nervous of cyclists should expect to have to do an emergency stop from 10mph. (I still have this fork, if you want to see it). A tandem fork for a 203mm disc must be substantially heavier duty than this! -
Lots happened lately. I've been wary of updating this thread because everything was up in the air, and almost everything that could have changed did so. We're not getting a Thorn anymore, we'll be riding a Co-Motion Java. Feels a bit like we went from old-school Somerset to bling West Coast.
On top of that, we're changing the route, mostly because of the seasons. There are a few places that we really, really want to explore: Kyrgyzstan/Tajikistan, rural China, SE Asia, and Japan. In our previous plan, we'd probably reach the Stans around Oct/Nov, which is not a great time to be there. Ideally we'd want to be there on Summer, but that'd mean either rush the whole first part of the trip (which would never work anyway) or skip the Stans to return on Summer 2019. But then we might be rather far from there, and u-turning wouldn't be so nice in any case.
The current solution is to reverse the order of the trip. We pick up the bike in America early July, then ride the West Coast for a couple of weeks. From there we fly to Japan, arriving early August for some hot and humid cycling. If we keep moving South towards Vietnam, we can have good weather pretty much the whole time. November is very mild in Southern China, and winter in SE Asia is not bad at all. We can linger around that part of the world until Spring 2019, when we head towards the Stans for Summer before crossing to Azerbaijan/Georgia/Turkey in Autumn. Winter in Greece, perhaps?
It's a very different concept, and something we struggled to come to terms with. We were fascinated by the romanticism of jumping on a bike and cycling out of the front door, using Europe as a gentle and familiar warm-up before Asia begins. But we're now a bit more confident that this new plan will be better. I was afraid of reaching Asia with little money, no curiosity, and a bit jaded by months of traveling. Like most people, I struggle to be in the moment, so perhaps a riverside beer in a Laotian evening would feel very different to me if a flight back to London life would be looming.
Update over, epic no pics fail.
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that's wicked
liked the spec on this one: http://bikingbakke.blogspot.co.uk/2013/10/co-motion-java-rohloff-detail-review.html
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That one has all bells and whistles. We thought about the dynamo/usb charger – we'll have SO MUCH stuff to charge – but I think we'll be fine without it. We're not planning to ride in the dark at all.
I'm jealous of their bottom bracket, ours will come with the FSA Mega Exo thingy that is reported to be made of jelly. We considered already speccing it with something better, but we'd have to source it ourselves and make sure it works with the tandem cranks, and whatnot. I assume Co-Motion has a deal for FSA kit, so we're going with that until failure, and then we replace for a Shimano one when/if necessary.
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Build specs are:
- Java Rohloff
- Gates carbon belt
- DT 540 tandem front hub / Velocity Cliffhanger Rims / 135mm rear / 100mm front quick-release axles / 36 spokes
- Schwalbe Marathons 700c x 38
- FSA Gossamer tandem cranks
- waiting to confirm if BB7s or Spyres/Spykes
Plus
- Tubus Logo rear rack
- Surly Nice 2.0 front rack
- framebags
- top tube bags
- rando bag
I don't know which bags yet, surely some custom job for the framebags. I have a GB rando bag but I'd have to get a new overpriced decauler. Quick release and strap would be nice too. So still studying that.
- Java Rohloff
PhilDAS
TvH
Heldring
spotter
platypus
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Asia on a tandem
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@ough
belt and braces approach, awesome