limit of development = pi x diameter of wheel x teeth on smallest chainwheel/teeth on largest sprocket
Upper limit of development = pi x diameter of wheel x teeth on largest chainwheel/teeth on smallest sprocket
For my bike
lower limit = 3.14 x 0.7m x 28/34 = 1.8m;
upper limit = 3.14 x 0.7m x 48/14 = 7.5m
(The chainwheel being the front set of cogs and the sprocket set the rear set of cogs.)
The development range is 1.8–7.5m. The upper limit is fine and is only used on the flat and downhill. The lower limit is important in the mountains. Spanish roads are mostly well graded and so most people, including occasional cyclists, can get away with a lower development of around 2.5m. If contemplating mountain and forest tracks think about a lower limit of around 1.8m as the tracks may be steeper and poor surfaces require lower gears. If the terrain is undulating or hilly a lower limit of 3.8m should suffice.
Maintenance
Your bike should be well maintained and physically sound. A well-maintained and correctly set-up bike is subject to less resistance and wear. A full service should be carried out prior to going. Cycle shops in rural Spain, although excellent, can be sparse.
Weight
Weight is important for several reasons. A loaded touring bike with rider would typically weigh around 100kg. Every extra kg increases the work required to get up a hill by 1%; conversely, a reduction of 1kg reduces the effort by 1%. In stop–start cycling the effort required to get moving depends on the mass of the body to be moved: the lower the mass the lower the effort. The rolling resistance of the tyres is dependent on the amount of tyre in contact with the road at any given time. This is dependent on the load divided by the tyre pressure; the smaller the load the smaller the rolling resistance. Therefore tyres should always be kept to the correct pressure. This is printed on the sidewall of the tyre.
Aisa (Route 7)
Lights – front and back
Although most cycling will be done during the day you may get caught out in the dark, and a number of the Vías Verdes have very dark tunnels with all-terrain floors. Make sure your lights work and replace existing batteries. Buying replacements in Spain will not be a problem. Position the lights so that when the bike is loaded they can be seen by passing traffic. (UK cyclists note that traffic will pass on your left.) At night cyclists must wear a reflective jacket that is visible at 150m.
Pannier rack and panniers
There is no need to carry more on your back than the clothes you wear. A loaded backpack can reduce cooling through perspiration, be uncomfortable, and raises the centre of gravity so decreasing stability. Put everything possible in the panniers. For most cycling a couple of rear panniers should suffice; if camping a handlebar bag can provide the extra space required. More kit can be strapped to the top of the pannier rack. If you need more volume think again. Lightweight aluminium racks are fairly cheap and sound. Front panniers tend to be smaller and while giving extra space (and weight) have the advantage of increasing stability by counterbalancing the rear ones. Take at least one elastic bungy cord for fastening things down. Some panniers claim to be waterproof, but line them with bin bags and have a couple of carrier bags to put dirty clothes in. Manufacturers to consider include Ortleib, Carradice and Vaude.
Water bottles
Most bikes have two sets of lugs for fitting water-bottle carriers. Use them both; cycling in warm weather is thirsty work. Plastic bottles can taint the water so fill them with water when new and allow to stand; empty, and repeat until the water tastes acceptable. Top up the bottles at the start of every day and at every opportunity. On long rides through empty country a large bottle of readily available still mineral water can be attached to the rack with a bungy cord.
Flavoured drinks in particular can encourage the growth of mould inside water bottles. Keeping them clean inside and out reduces the chances of contracting gastric disorders.
Tyres and wheels
Make sure they are in good condition at the start, and if in doubt replace them before going. Tyre type and choice is importance for comfort and ease of cycling. Fatter tyres contain more air and give a more comfortable ride, but their higher rolling resistance is more tiring. If travelling light, ie. two full panniers, then a good compromise is to use a 25mm tyre on the front wheel and a 28mm one on the back. If the load is heavier, such as when camping, then consider 28mm front and 32mm rear. This is assuming that the wheels are compatible. Correct tyre pressure will reduce the number of punctures caused by bumps on rough roads. Tyre tread depends on which type of cycling you intend to do – the more off-road riding is planned the deeper the tread should be.
What To Take
Air travellers are typically given a luggage allowance of 20kg (of which 5kg can be taken into the cabin). If the bike is charged for separately it will have its own additional allowance. 20kg should be more than enough. Unless you are camping, if your bike and baggage comes close to or exceeds 20kg in total, then you should seriously reconsider what you are taking as heavy loads can become an unwieldy and tiresome burden.
Bike
Any bike fitting the criteria described earlier will suffice.
Pump
You will certainly need one if going by air. A pump with a pressure gauge is recommended.
Helmet
The wearing of cycle helmets in Spain is compulsory. They must be CE marked and made to international standards such as EN1078. There are exceptions in cases of extreme heat, prolonged climbs or on medical grounds.
Lock
A good U-bolt or cable lock removes worries over security. The weight is worth it.
Tools and spares
A well-maintained sound bike should give very little trouble on a tour. However, do expect to adjust brakes and derailleurs and to repair punctures. The odd spoke may also give way. Tools can easily be shared within a group. If going by air remember to take the tools required to dissemble and assemble your bike before and after the flight.
Puncture repair kit
Spare inner tube (one for every two in the party)
Tyre levers (10cm-long plastics ones are sufficient)
Spanner to undo the wheel (multi-head is better than adjustable as it is less likely to damage the nut) – quick-release wheels are even better
Adjustments: flat blade and Phillips screwdrivers, Allen-keys for all Allen-bolts on bike (typically 4, 5, 6 and 7mm), chain riveter/extractor, oil (3 in 1 or similar in non-aerosol container)
Spoke replacement: see above for the tools to remove wheel from bike and tyre from wheel. Replace the broken spoke but don’t tighten too much; set the wheel back in the upturned bike. Use the bike frame and brake blocks as a jig to measure any buckle. Tighten and loosen the replacement spoke using a small adjustable spanner or a spoke-nipple tool until any buckle has gone. Normally adjusting only the replacement spoke will sort out any problem. The objective is to make your bike sufficiently roadworthy to continue. Small buckles can be sorted out later by someone who has had a bit more practice.
Spares: very few spares are required. Take a spare inner tube to swap for a punctured one; the repaired one then becomes the spare. Some spokes (taped to the pannier rack); a broken spoke can easily buckle a wheel. A replacement may not make the wheel perfectly true but will be tolerable. Spare nuts and bolts just in case pannier racks or mudguard lose their means of fixing. A small roll of tape and a length of stiff wire, no use yet – but maybe someday.
Cycling clothes
Wind resistance is reduced with tighter-fitting clothing. As the weather will be perfect clothing can be kept to a minimum.