Start with the bicycles...
The most ideal bicycle depends on what ones cycling needs are, but for a start, one needs one that can take a pannier rack as if one is going to carry things, the rack (Rear carrier) is essential, and before one goes and buys any bike in the hope a rack will do its job, a word about the very most basic principles in bicycle geometry with a traditional diamond, or similar style frame is that the longer the frame wheelbase is, the more stable the bike is when loaded up with panniers so the bike will be easier to control, BUT we also have the shorter the wheelbase is, the better the bicycle will accelerate. Shorter wheelbase bikes are more twitchy and have steeper geometry frame angles. The shortest wheelbase bikes apart from specialist bikes for certain tasks such as bicycle polo are usually time trialing bikes, which are only built for max speed on a short distance (E.g. 10 mile, 15 mile, 25 mile etc) or racing bikes which have a slightly longer wheelbase but still too short to be practical other than the afternoons ride when all one needs to carry is oneself, but neither of these are built to carry anything else.
Then we have the purpose built load carrier, he traditional touring bike, with its stable longer wheelbase and frame designed to still be efficient and comfortable and yet not overly heavy. In other words, it is not ultra lightweight, but is not as heavy as a mountain bike or a heavy beach cruiser. (All bikes which have their place, but one will find them overkill when it comes to ones actual needs. Is like buying a large SUV to pull a little 2 birth caravan when a medium sized or even some smaller cars will be all one needs! Some of the older mountain bikes will work fine as a heavy duty all-round tourer as the geometry used in the 1980's was actually somewhat similar to touring bikes. By the time the early 1990's came along, geometry changed, but still not too bad apart from them being a little too heavy. Don't bother with any full suspension bike unless one is confining oneself to tow a trailer. Some racks are available for them BUT they are a compromize and will not handle heavy weights.
Now there are bicycles that were in between racing bikes and tourer and were known as sports tourer. These were made for those who could only afford to buy one bike and wanted to do a time trial or race on the weekend, but also used their bike for commuting. These bikes have disappeared. Touring bikes hardly exist today as markets are fashion lead. I suppose audax bikes are the closest to sports tourer, BUT audax bikes are not designed to carry any racks. Sports tourer are designed for racks BUT will be twitchy to ride. (Most racing bikes sold as racing bikes from the past on the cheaper end of the market had sports touring geometry and NOT racing geometry, as they recognized that most cyclists would not race, but wanted a bike that felt as if it could race, and sports tourer can actually race, though a racing bike is better if one is racing. Racing bikes do not have any bolt holes for fixing carriers to).
Carriers. Older carriers had three point frame fixings. Then came four point frame fixing carriers. Later still, one had wide type carriers for use on disc braked modern bikes. Unless one has a disc braked bike, avoid these wide carriers as they are too much of a compromize, and actually a compromised design with disc braked bikes where one does not really have an option. My choice would be to use rim brakes and here is why. Brake blocks are always available in all good bike shops without the need to order as there are only three or four types of rim brake block designs. So one does not have to order in the hope ones bike will have working brakes again in the next few weeks or even months like one can be left with if one has disc brakes, as when I left the cycle industry there were over 40 different disc brake pad designs, and when I last had a chat, they say it is now hundreds, which means they have to order the right one, and some are no longer available. Is crazy to be honest, and manufacturers can basically charge what they like knowing one has no choice but to buy from them! We never had this issue with rim braked bikes, so if one has the choice, get a rim braked bike and buy some spare brake blocks anyway, (They are cheap), and one will be set for a fair few years!
There is a nice type of bike I have not mentioned which is also generally good at load carrying and that is the hybrid bike. These do come in different types as some are basically 700c wheeled mountain bikes (Almost pointless. Why not get a mountain bike?), and others at the other end of the hybrid term are basically flat barred racers which are no good carrying things.
Now another bike built from the offset for carrying loads are workbikes often made for businesses and industries which can carry huge weights, but at a slower pace. Great for heavy loads but usually lack gearing for steep hills and also are going to be heavy so not quite so suitable, though the odd lighter weight traditional style bike is going to be ok.
About gears and gearing. Two trains of thought, as basically it is not necessarily the number of gears, but rather the range of the gears that one may look at here.
The first train of thought is to have a wide range of gearing. Obviously to avoid massive jumps in gears, the wide the range the more one ideally needs inbetween, though one need not go too silly, as with deraileur gear systems, cramming too many cogs onnthe rear wheel means thinner cogs and thinner chains and chain angles increasing in angle (Especially if a single chainring near the pedals is used, which only does one thing! Increases wear so one will be wearing out transmissions in no time. Why cycle trade are doing this! Even professional mountain bikers don't like them but have no choice due to sponsorships. Is a fashion gimmick designed to increase trade, and those bikes will never be as efficient as older bikes with only a few cogs on the back. Why? The wider the rear axle and wheel are, and the more angle on the chain, the less efficient the drive will be. (WHY ONE SHOULD NOT BE TEMPTED TO TAKE AN OLD BIKE AND BEND THE FRAME TO FIT MORE GEARS! As bikes with 8, 9 or more cogs on their freehubs will have heavier frames which are stiffer and stronger to compensate, so ones older frame will be far less efficient with having more gears than if one had left it as it is. If one wants to widen them slightly to a seven cog freewheel when it was designed for five, it is the best compromize, but don't go beyond there. The actual old single speed bikes with their narrow hubs and frames had the most efficient drives of all as the chain angle is direct and straight.
But now we come to the next train of thought. One only usually uses a few gears on a ride. If a hill is too steep, and one only comes across a steep hill once or twice on a typical ride, why not go for less gears and maybe a hub gear instead. True, deraileur gears or single speed are more efficient than hub gears, BUT hub gears (If one has a low number of gears such as 3 for example will outlast anything else. To make it more practical,ma 4 or 5 speed may be better, but take it from me who owns an12 speed hub gear, and has tested bikes with 8, 9 and even more than my Sachs 12 speed, there are a lot more moving parts in there. The more moving parts, the more friction AND the smaller the individual parts are, so the more likely they are to go wrong. My 12 speed Sachs Elan hub gear as an example still works. Yet, out of all those hubs they made, I do not know of a single other cyclist who has one that still works, and these were only made around 25 years ago, if that!
Yet, the old 3 speed hubs... Not a lot went wrong with them! Pawl springs rusting through due to neglect where they were stored in damp conditions without being used, so the internal oil didn't get to keep the springs oily is the only real common failure apart from bent axles or the internal changing plates threads going where the toggle chains screwed into. Apart from one hub which was totally ceased solid as had no oil (Total lack on maintenence) and the bike had been left outside on its side in the rain for years by the look of it, so one could say it was totally neglected, and apart from the odd issue such as mentioned above, the 3 speed hubs we serviced made by Sturmey Archer just went on and on and on! Toggle chain replacements as those wore and broke were the most frequent part needed replacing, and they lasted a few years in use before they wore. Hub gears, as long as one keeps the gear numbers low so there are less moving parts inside, and they last. Only downside to the longer lasting designs is a lack of gearing range.
The most ideal bicycle depends on what ones cycling needs are, but for a start, one needs one that can take a pannier rack as if one is going to carry things, the rack (Rear carrier) is essential, and before one goes and buys any bike in the hope a rack will do its job, a word about the very most basic principles in bicycle geometry with a traditional diamond, or similar style frame is that the longer the frame wheelbase is, the more stable the bike is when loaded up with panniers so the bike will be easier to control, BUT we also have the shorter the wheelbase is, the better the bicycle will accelerate. Shorter wheelbase bikes are more twitchy and have steeper geometry frame angles. The shortest wheelbase bikes apart from specialist bikes for certain tasks such as bicycle polo are usually time trialing bikes, which are only built for max speed on a short distance (E.g. 10 mile, 15 mile, 25 mile etc) or racing bikes which have a slightly longer wheelbase but still too short to be practical other than the afternoons ride when all one needs to carry is oneself, but neither of these are built to carry anything else.
Then we have the purpose built load carrier, he traditional touring bike, with its stable longer wheelbase and frame designed to still be efficient and comfortable and yet not overly heavy. In other words, it is not ultra lightweight, but is not as heavy as a mountain bike or a heavy beach cruiser. (All bikes which have their place, but one will find them overkill when it comes to ones actual needs. Is like buying a large SUV to pull a little 2 birth caravan when a medium sized or even some smaller cars will be all one needs! Some of the older mountain bikes will work fine as a heavy duty all-round tourer as the geometry used in the 1980's was actually somewhat similar to touring bikes. By the time the early 1990's came along, geometry changed, but still not too bad apart from them being a little too heavy. Don't bother with any full suspension bike unless one is confining oneself to tow a trailer. Some racks are available for them BUT they are a compromize and will not handle heavy weights.
Now there are bicycles that were in between racing bikes and tourer and were known as sports tourer. These were made for those who could only afford to buy one bike and wanted to do a time trial or race on the weekend, but also used their bike for commuting. These bikes have disappeared. Touring bikes hardly exist today as markets are fashion lead. I suppose audax bikes are the closest to sports tourer, BUT audax bikes are not designed to carry any racks. Sports tourer are designed for racks BUT will be twitchy to ride. (Most racing bikes sold as racing bikes from the past on the cheaper end of the market had sports touring geometry and NOT racing geometry, as they recognized that most cyclists would not race, but wanted a bike that felt as if it could race, and sports tourer can actually race, though a racing bike is better if one is racing. Racing bikes do not have any bolt holes for fixing carriers to).
Carriers. Older carriers had three point frame fixings. Then came four point frame fixing carriers. Later still, one had wide type carriers for use on disc braked modern bikes. Unless one has a disc braked bike, avoid these wide carriers as they are too much of a compromize, and actually a compromised design with disc braked bikes where one does not really have an option. My choice would be to use rim brakes and here is why. Brake blocks are always available in all good bike shops without the need to order as there are only three or four types of rim brake block designs. So one does not have to order in the hope ones bike will have working brakes again in the next few weeks or even months like one can be left with if one has disc brakes, as when I left the cycle industry there were over 40 different disc brake pad designs, and when I last had a chat, they say it is now hundreds, which means they have to order the right one, and some are no longer available. Is crazy to be honest, and manufacturers can basically charge what they like knowing one has no choice but to buy from them! We never had this issue with rim braked bikes, so if one has the choice, get a rim braked bike and buy some spare brake blocks anyway, (They are cheap), and one will be set for a fair few years!
There is a nice type of bike I have not mentioned which is also generally good at load carrying and that is the hybrid bike. These do come in different types as some are basically 700c wheeled mountain bikes (Almost pointless. Why not get a mountain bike?), and others at the other end of the hybrid term are basically flat barred racers which are no good carrying things.
Now another bike built from the offset for carrying loads are workbikes often made for businesses and industries which can carry huge weights, but at a slower pace. Great for heavy loads but usually lack gearing for steep hills and also are going to be heavy so not quite so suitable, though the odd lighter weight traditional style bike is going to be ok.
About gears and gearing. Two trains of thought, as basically it is not necessarily the number of gears, but rather the range of the gears that one may look at here.
The first train of thought is to have a wide range of gearing. Obviously to avoid massive jumps in gears, the wide the range the more one ideally needs inbetween, though one need not go too silly, as with deraileur gear systems, cramming too many cogs onnthe rear wheel means thinner cogs and thinner chains and chain angles increasing in angle (Especially if a single chainring near the pedals is used, which only does one thing! Increases wear so one will be wearing out transmissions in no time. Why cycle trade are doing this! Even professional mountain bikers don't like them but have no choice due to sponsorships. Is a fashion gimmick designed to increase trade, and those bikes will never be as efficient as older bikes with only a few cogs on the back. Why? The wider the rear axle and wheel are, and the more angle on the chain, the less efficient the drive will be. (WHY ONE SHOULD NOT BE TEMPTED TO TAKE AN OLD BIKE AND BEND THE FRAME TO FIT MORE GEARS! As bikes with 8, 9 or more cogs on their freehubs will have heavier frames which are stiffer and stronger to compensate, so ones older frame will be far less efficient with having more gears than if one had left it as it is. If one wants to widen them slightly to a seven cog freewheel when it was designed for five, it is the best compromize, but don't go beyond there. The actual old single speed bikes with their narrow hubs and frames had the most efficient drives of all as the chain angle is direct and straight.
But now we come to the next train of thought. One only usually uses a few gears on a ride. If a hill is too steep, and one only comes across a steep hill once or twice on a typical ride, why not go for less gears and maybe a hub gear instead. True, deraileur gears or single speed are more efficient than hub gears, BUT hub gears (If one has a low number of gears such as 3 for example will outlast anything else. To make it more practical,ma 4 or 5 speed may be better, but take it from me who owns an12 speed hub gear, and has tested bikes with 8, 9 and even more than my Sachs 12 speed, there are a lot more moving parts in there. The more moving parts, the more friction AND the smaller the individual parts are, so the more likely they are to go wrong. My 12 speed Sachs Elan hub gear as an example still works. Yet, out of all those hubs they made, I do not know of a single other cyclist who has one that still works, and these were only made around 25 years ago, if that!
Yet, the old 3 speed hubs... Not a lot went wrong with them! Pawl springs rusting through due to neglect where they were stored in damp conditions without being used, so the internal oil didn't get to keep the springs oily is the only real common failure apart from bent axles or the internal changing plates threads going where the toggle chains screwed into. Apart from one hub which was totally ceased solid as had no oil (Total lack on maintenence) and the bike had been left outside on its side in the rain for years by the look of it, so one could say it was totally neglected, and apart from the odd issue such as mentioned above, the 3 speed hubs we serviced made by Sturmey Archer just went on and on and on! Toggle chain replacements as those wore and broke were the most frequent part needed replacing, and they lasted a few years in use before they wore. Hub gears, as long as one keeps the gear numbers low so there are less moving parts inside, and they last. Only downside to the longer lasting designs is a lack of gearing range.