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The Bike
If
you are reading this page I am going to assume that you have a genuine
interest in bikes and tandems in particular. If not it’s probably about
the right time to read another page! The reason for including the following
notes is to attempt to answer some of those questions that we pondered
on before specifying the bike.
The bike is a Thorn Cycles Raven Discovery tandem. As tandems go it is a really superb machine. When crawling uphill we would gladly swap all of its superb features for a 250cc engine, but when the going is good it is very very good.
In brief the frame is M/M size fitted with S+S connectors for easy transport (S+S fittings allow the frame to be split just in front of the pilot’s seat post splitting the tandem into two parts which is much easier for transportation). The gear system is a 14 speed Rohloff speed hub. Brakes are Shimano XTR working against Sun Rhino wheels with ceramic rims. We chose not to fit a disc brake, but the Rohloff gear will accept one should we decide that it’s a good idea at a later date.
Overall the performance of the tandem has proven to be excellent with the Rohloff gear proving to be absolutely brilliant. The speed hub allows change of gear when stopped. This is extremely useful at junctions when the pilot has failed to have sufficient forethought to get into the right derailleur gear 10 yards before the junction or has simply been caught out by some aspect of road geometry or traffic conditions. It is also supremely smooth and works well even when it is raining cats and dogs when derailleurs get noisy and sticky. The S+S fittings will be useful on the LE-JOG trip since we have found that when broken down (which takes about 5 minutes or less), the tandem will fit in the back of a moderate estate car and still allow 4 passengers to travel in reasonable comfort. The Shimano XTR brakes are very powerful and for normal road riding seen to obviate the need for a disc brake. A drag brake can’t be fitted to a Rohloff hub in any case, but it perhaps remains to be proven on the trip as to whether a drag brake might have been useful (more about brakes below). Pedals are Shimano SPD and these have proven to be an excellent upgrade from the toe clips which we previously used. We have had a few minor mishaps but we are now getting used to early unclipping and getting the communication right! Saddles were originally Brooks B17, Graham has found his to be fine but I have had considerable troubles, so our advice on this subject would be entirely contradictory! One omission from the bike as we specified it was a rear suspension seat post. After swapping one from my solo bike on a recent ride I am convinced that this is a very advisable accessory for the stoker. Sitting directly above the back wheel the ride is hard and leads to a badly aching pelvis after 50 miles or so. At the time of writing I am experimenting with a "Comfort Saddle" and I have added some notes on this towards the end of this page.
Choice of tandem manufacturer
With my eyesight
having deteriorated to a point where cycling with our Rotary group was
beginning to have its difficulties, I had stopped solo cycling. In a moment
of inspiration or lunacy depending on your viewpoint Graham asked me in
2005 whether I would fancy doing the planned
After looking
for a while at various dubious offerings on Ebay
for which my bids were mercifully unsuccessful, I decided to take the
plunge and buy a Thorn Explorer. This looked good on the grounds of reviews
and reputation. Perhaps most crucially the price was within my budget
bearing in mind that at this time it was not really proven how much it
would be used. This was a very good machine which rode very well and was
extremely stable at speed. During 2005 we trained for the
As Graham puts it “ In the dark days of November” he was challenged by his son Oliver to complete the LE-JOG trip in 2006. Graham emailed me asking if I liked the idea of doing LE-JOG on a tandem. I think that I rather shocked him by simply replying “Yes”. After starting to read up on the LE-JOG trip I became concerned that the Explorer was not up to the job. Robin Thorn in initial discussions had recommended a higher spec machine than the Explorer for two males to ride due to weight and strength constraints. Adding luggage and expecting the Explorer to survive the 1000 mile trip was in doubt. Since by this time Graham and I felt that we were likely to make good use of a high spec machine, we bit the bullet and upgraded to the Raven Discovery as described above. Despite being an expensive purchase, we have been extremely pleased with the machine and we are confident that it won’t let us down. In fairness though the ride is very similar to the Explorer.
Tandem brakes:
I spent a lot of time thinking about tandem brakes and reading up everything that I could find on the subject. Here are a few interesting links:
http://www.sheldonbrown.com/tandem-brakes.html
http://www.tandem-club.org.uk/cgi-bin/db_config.pl?noframes;read=4994
http://www.tandem-club.org.uk/cgi-bin/db_config.pl?noframes;read=5216
http://www.sudibe.de/articles/billondiscbrakes.html
Originally this interest started off as a concern that the Explorer had only rim brakes but with a rear wheel upgrade could be fitted with the Arai drum brake. The Arai brake is apparently no good as a stopping brake but is a very good “drag brake” used to moderate speed on long dissents. The Arai is specified to dissipate large amounts of heat and so can be left on permanently during the downhill ride. This cannot be done using rim brakes because the heat build up can be so severe that inner tube joints can melt and catastrophic failure can result. Disc brakes have a similar heat build up problem and tests have shown that many disc brakes will fail under extreme stress on a tandem.
So what to do? The problem
is apparently only a serious danger on very long descents and the solution
turns out to be a form of cadence braking. This requires the tandem crew
to not be timid but allow speed to build up so that some energy is lost
to wind resistance and then when speed is at maximum comfortable, brake
fairly hard to a low speed and then the process is repeated. On the Discovery
the rim XTR brakes are very effective and since the addition of a disc
brake added £500 to the cost of the bike (when the hydraulic linkage to
allow use of S+S frame fittings to be used was included) we chose not
to fit it. By the end of the LE-JOG ride it will be interesting to see
if we will wish that we had, but at the present time there is no indication
to suppose that we will. Descents of the
The "Comfort Saddle"
Ever since I can remember, I have struggled with saddle discomfort and this has always limited my riding distance to a greater extent than my legs. I had found gel saddles to be OK but still painful on a long run. Having read reports from Brooks fans, I was keen to try one out on the new tandem. There is clearly something very odd about my skeletal anatomy because after a few rides I was convinced that the Brooks B17 should have a place in the Tower of London Museum hung alongside all of the other implements of torture. After 50 miles any secrets which I may have known would have been gladly yielded if only the pain would stop. I tried the trick of a wet towel applied on the saddle for 30 minutes before a ride and that did improve things dramatically. Finally a suspension seat post was tried and this was in fact getting towards a tolerable solution. I was still a bit concerned because I found that I had to tilt the saddle up at the front to avoid slipping forward onto the horn, which was even more uncomfortable. This seemed to fly in the face of all saddle related medical advice, so apparently not good. After much ado, I spent some time reading about nose-less saddles in which respect the following website was useful: http://www.nonose.com. Several offerings are available in the UK and I plumped for the "Comfort Saddle Company".
The saddle was ordered and arrived quite promptly. It is quite an odd looking thing and if you are shy of ridicule from your family and friends then prepare for a hard time! Looks like something off the Bat-mobile according to my daughter. However once she sat on it she could see the point, or perhaps that should be the lack of it. Having no front nose to the saddle, the whole weight of the body is placed on the pelvis sit bones exactly like when you perch on the edge of a bar stool. The saddle is firmly padded and so is quite comfortable. To accommodate the natural tendency of the pelvis to swing as you pedal, the saddle is allowed to tilt with you by means of a spring mount. There is a tendency to slide forward on the saddle but this is partly a matter of getting used to it and the angle at which the saddle is positioned. The rocking of the saddle and the occasional need to reposition oneself on it is a bit disconcerting for the tandem pilot, but not a problem as long as not during critical maneuvering. At the time of writing I have done some 135 miles on the saddle and it does seem to have solved a lot of problems. A decision will be made at the 200 mile point
