How would you modify a bicycle to make it more efficient?

Replies

• 

  Ashraf HZ

  John Hopkins University had tested the chain drive's efficiency. They managed to get a a max of nearly 99%. Quite remarkable!
  
  Source -> ET 11/99: Pedal power probe shows bicycles waste little energy
  
  I believe efficiency gains can be gained more from reducing rolling resistance from proper tires. Carbon fiber frames might be useful, but their prices are not really accessible to everyone at the moment.
  
  We might look into improving the chain drive's consistency rather than think of a completely new way.
• 

  Rohan_sK

  The frictional resistance between the road and the tyres is exactly what is providing the turning moment for driving the bike.
  
  We can reduce the weight of the bike by using lighter materials for the framework, so that the inertia can be reduced, giving a better speed for applied effort. And the frictional force defeciet( ground contact) for driving the bike can be compensated by using a better tyre profile or a rubber with greater coefficient of friction, or wider tyres. This is because the reduction in the weight will decrease the normal reaction ultimately reducing the friction. The optimal value of this frictional resistance for turning the bike must be considered.
  
  The chain - sprocket combination is considered the best transmission media reducing the chances of slipping ( as in belts), but some other medium can be thought of.
  Also the air resistance caused by the driver can be reduced by modifying the sitting position ie bend a little while driving ( I think this is done in racing).
  
  Also we can use shock absorber or dampers which can store the shock energy (from bumps on the road) and convert it to some useful electrical impulse which can inturn be connected to a sysytem using this power to rotate the wheels whenever manual efforts are relieved due to fatigue or when the bike is under load say uphill drive or something like this. Its a very crude idea and needs much refining ,so Ceans can add more to it to make it more applicable.
• 

  gohm

  That's easy Biggie, just add a motor! =)
• 

  krishthd

  ya u r right. all the modifications r being made to cars but not the bikes r concentrated.
  we can increase the eff. by better aerodynamics. I think we can attach an additional motor wich in combination with the engine gives better output.
  for this motor we shud use a more powerful battery wich can run it.
  
  Or we can use 2 motors for the 2 wheels of the bike wich run the same battery wich is more powerful.
• 

  Rohan_sK

  I think , Big_K had suggested that the driving would still be MANUAL and not involve MOTORS!!
• 

  Ashraf HZ

  @ Rohan_sK
  I hope you did not misread my friction comment. I was talking about "rolling" rather than "frictional". Deformation may cause reaction forces that opposes the direction of motion. Hysteresis would also cause loss of energy through heat 😀 Thus, other than the tire profile you mentioned, the material of it also must be taken into account.
  
  I think we should all realize that efficiency means the how much of the energy power inputted is converted to useful energy. Adding a motor does make it easier to ride for us, but it doesnt necessarily add to its efficiency.
  
  If we do plan to add a motor, we'd need to get a highly efficient motor. Normal DC ones have efficiency of 50-60%. Also, from where would you primarily get the electricity from? P.V cells are still commercially below 30% efficient. And getting it from mains makes it dependent on a source.
  
  Thus, the assumption is.. how do we modify the bike to convert as much of OUR energy into useful power that allows us to travel over distances?
• 

  ShrinkDWorld

  To increase efficency I will provide some essential sagestions=>>
  At first we can not reduce the friction between tyres & road surface At this moment it is already less. If we try to reduce It will take effect on grip of tyres.
  1) At frist remove all the unnecessary accesaries of cycle i.e mirror , mudgards,chain cover etc.
  2) After every month cheak the tenstion in the chain It will be gratly affect the efficency.
  3) you must have to use gears at weel & paddle
  4) It shude be well balance bearing in good condition
  5)Use proper pressure in tyres. or you can use tube less tyres
  6)The hight of seat shude be in proper height. It will be in position so that rider's become streat without lossing contact from paddle.
  7)YOu can use DC motor on top gear on dry cell (It will charge sepretaly from outside)
  plz comment on these instructions.
• 

  Rohan_sK

  @Ash
  I think you got a bit confused with Rolling resistance and Friction.
  The Rolling Resistance that you are talking about is essentially the Frictional Resistance ( in Rolling) and the Friction you are mentioning is the SLIDING FRICTION. This Rolling Resistance is exactly what provides the Turning Moment. ( I hope I've interpretted you correctly this time, if not feel free to write again:smile😀.
  
  @Ash
  And I've already mentioned about the Material of the tyre ( refer : Providing rubber with a better Coefficient Of Friction)
  
  And The inclusion of motors is a good option, but it wont be remaining purely manual drive anymore, thats the reason I didnt include it.
  
  And its nice to see guys like you from Electronics having interest in Mechanical things😁 Keep it up!!
• 

  Ashraf HZ

  Hm, I admit I'm even more confused 😛
  
  Just to see if we are on the right page.. we want to reduce the rolling resistance, yes?
• 

  Rohan_sK

  You're right, but simple class 12 physics seems strangely confusing!!!! ....
• 

  maxz

  Hurm~!!!! I think the body of the frame have to be mobs a bit by mobbing it with some angle to reduce the air frictions against our body. As u see, if the raiders ride the bike at 60 degree bending down forward, the atmosphere pressure and force is against the raiders body. To reduce this kind of natural friction we shud lowered down the front part of the bike frame silghtly. If this may be possible, it will help the raiders to ride on bike more efficiently.
  
  This is all about guessing. Because i experince that when i ride on my bike, i feels that some kind of thing was pulling me backwards instead of forward. THen i was thaught that the air pressure is againt our body. thats why it cause me pull backwards a bit while i riding on my bike.
  
  Correct me if i'm wrong.
• 

  looknice

  Hi The Big K,
  I liked a lot your approach to the bicycle developments.
  I would propose another point of view.
  Let's think to the engine efficiency. I mean the human engine.
  If we give a look to the Eco-Shell Marathon we discover that with less than 20 Watth an internal combustion engine vehicle can run at 30 km/h!
  Very efficient.
  Perhaps is there something wrong between the man and the bicycle?
  My friend Francesco studied it and found that human engine is really very inefficient when interfaced to the pedal crank.
  His example "...how many attempts have been done on the sole stiffness of the cycling shoes without ever noticing that the foot on a hollow rod rotating around the malleolus can only “fall”! " is really simple and clear.
  His BDS system try to reduce to the minimal this inefficiency.
  BDS pro - YouTube
  
  
  
  [youtube]tOyrm4tl2ck[/youtube]
  Maximal efficiency and minimal energies that means efficiency in happiness.
  Sorry for my poor english.
  Ciao
• 

  Kaustubh Katdare

  Hi Look Nice,
  
  Thank you. It would be wonderful to have your friend on CE and share his designs. Would love to have a look at the BDS Pro.
• 

  gohm

  Cool idea! other points of improvement could be to reduce loss due to friction. This would be in points like sprocket/chain, wheel bearings/hubs.
• 

  Kaustubh Katdare

  gohm

  Cool idea! other points of improvement could be to reduce loss due to friction. This would be in points like sprocket/chain, wheel bearings/hubs.

  Typically, I'd want something to store mechanical energy which can be used later when the bike is moving uphill.
  
  I could only think of a flywheel, but that's been ruled out because it'll increase the weight of the bike. A battery & a motor would be a good idea, however I'm not too sure if we're really being innovative here.
  
  Any newer methods, folks?
• 

  ShrinkDWorld

  To Big k=>
  we can use spring but it is lightly heavy. But instead of it we can use dry cell
• 

  Kaustubh Katdare

  @gg_gaurav: Yep, anything that you think would be useful.
• 

  Rohan_sK

  @ Big_K: I had a similar thought of storing the mechanical effort/energy and use to power the bicycle when the driver is tired or on an uphill traverse. ( I have already mentioned in my first post on this thread itself, about using a system with suspensions in the form of shock absorbers which can use the shock energy from the bumps or pits on the road and convert this energy into some electrical impulse which can be used to charge a small battery. This battery can power a small motor which can drive the wheels on the uphill terrain:smile:.)
  Another way to do the same thing would be to use small fans on suitable locations on the frame where the wind flowing by ( due to bicycle motion) can be utilised to run the fans which inturn can rotate a small generating device. The amount of electrical energy ( though small) can be ued to charge a battery ( though the elctrical energy produced in unit time may seem small, it is considerable that the driving time will be relatively longer than the time span for which this power is required ie for uphill ride or when the rider is tired), this can charge the battery during most of the normal mode riding with small inputs at a time. This can again power a motor which will couple to the rear wheel drive and supply the extra drive force needed to ride the bicycle on an uphill terrain.
  There can be a set of 4-6 fans placed at suitable locations on the frame in the front as well as sides, and connect them to the generator which will be wired to the batteries. The batteries connect to the motors which will be coupled to the driving wheel through a set of small gears.
  The only point of reconsideration here is the weight to power ratio, as the system with battries, motor, wiring, gears( though all small specs) will add to the weight of the bicycle which is undesirabe. But it can be worked out.
• 

  g_rakesh2

  Innovations in bicycle are always continued from when its invented, in first phase it was a single wheel and there after alot of changes have made in desogn to increase the performance.
  The innovative rotor pedal system continues this evolution by utilising independent cranks that are not aligned at a fixed 180' to eliminate the "dead point" that occurs when conventional pedals are vertically positioned.Anyone who has tackled a very steep hill on a bicycle will understand the concept of a dead point.
  
  You always find that the moment at which you are forced to get off the bike and walk is when you are at the top of the pedal stroke - this is because at this dead point the rider has the least mechanical advantage with neither leg able to transmit any power. So if heading uphill, with no momentum to compensate, you find yourself getting out of the seat to increase leverage at this dead point.
  The rotor system solves this problem by using cranks that never allow one pedal to coincide at 180 degrees to the other. The independent cranks that are synchronised by means of an exocentric axel and two rods, which vary the transmission ratio during the cycle and prolong the power stroke phase for a more efficient transfer.
  What all this means in real terms is that by the time one crank is at the bottom of the stroke and in the six o'clock position, the opposite crank has been accelerated through to the one o'clock position and has already started the power stroke phase. In addition to increasing efficiency, traction and maintaining a smoother cadence, the rotor system reduces the risk of knee injuries and tendonitis that are attributed to the leg pushing on the upper dead point.
  According to the manufacturers, tests on the rotor have demonstrated a real increase in power of up to 16% (equivalent to an average advantage of 3 minutes in an hour), and a resultant reduction in lactic acid and cardiac effort.😁
• 

  g_rakesh2

  what if bicycle built with bamboo.
  Its durable, strong and flexible and light wieght too.
  for more information go through this..
  #-Link-Snipped-#😁😁😁
• 

  ShrinkDWorld

  g_rakesh2==>>
  Nice idea!!!
  Rohan_sK==>
  good Idea. But we can not get more power from that fan Because if we tru to get more power It will increase resistanc.But it is usefull While in parking also.
• 

  Rohan_sK

  Yes I am aware of the induced drag due to the fans , but the blades would be designed with aerodynamic considerations and the blade profiles will be in accordance trying to minimize the drag.
  These are all the real time practical design issues which need to be actually tested.
  Lets have some more ideas and innovations coming in from everyone!!
• 

  aprhockey

  g-rakesh2: I looked into the Rotor pedal system and it turns out that there is no significant advantage to using them.
  
  #-Link-Snipped-#)
  
  Another innovation by Rotor is the q-ring (an elliptical chainring)... however, I am skeptical of these also. They are designed so that when the pedals are at the dead point, there are fewer gear teeth to make it a faster transition back to the power stroke position.
  
  #-Link-Snipped-#
  
  It'd be awesome if this thread was brought back to life
• 

  satanas

  Hi all,
  
  Bicycles should be manually, including motors is a bad idea..else we would call it a motorbike.. am happy with my bicycle,just that it's a bit heavy. so i really think that if we want to have a more efficient ride, we need to consider lighter materails for construction and the profile or design (the frames).. Guys, if you mean 'aerodynamics' is relative to the rider's posture think also about your HEALTH (bending your spine!).. i will go for profile redesign (including aerodynamics kits).. Anyway, i think we should all invest our thoughts on how to reduce drag force first!!
  
  regards,
  Satanas
• 

  gohm

  rider position to maximize power efficiency & center of gravity is a good idea in addition to reduced weight and friction. How about adding power via using arms as well to drive the bicycle?
• 

  aprhockey

  I think the key to making the bicycle more efficient is not to necessarily reduce lost energy due to friction (other than aerodynamics, there's not much left to reduce this), but to capture the lost energy and put it back into use.
  
  It was mentioned earlier that we could capture lost energy from the suspension in mountain bikes. Students at Georgia Tech used this idea to power safety lights in 2007, but maybe the energy could be used to help accelerate the bike (even if its not much energy). I'm sure it's worth looking into.
  
  When it comes to the idea of using both arms and legs, i think we're on the right track here, however, steering would be difficult if the hands were occupied.
  
  I strongly agree that reducing drag due to air is important, but we must keep in mind that the bicycle is so great because of its practicality and relatively low price compared to other forms of transportation. The bicycle has reached a record of 81 mph, however the rider can't even put their feet down because they are completely enclosed, which is not practical.
• 

  satanas

  please, first specify what do we want to achieve here?? speed or comfort or both? and is it for sports bicycles-competition- or those you use to go to the sea with your friends and give a ride to your beautiful gfs 😉 ???
  
  Regards,
  satanas
• 

  aprhockey

  I may be thinking about this differently than others. I was thinking of how to make the average bicycle more efficient for the average person using it to commute. So, I guess I am thinking about modifying the bike for more efficient transportation.
  
  This probably makes it more difficult also, because the bicycle still needs to be practical and comfortable (easy to get onto, easy to store, easy to move around in traffic would help, and easy to fix).
  
  Perhaps there would be a way to capture the thermal energy the body creates and use that to power a small motor. Also, would the concept of regenerative braking be feasible (I really don't know anything about regen. braking). Anybody have ideas on that?
  
  For aerodynamic efficiency, I think that is the purpose of the recumbent bicycle. The rider is not in an upright position, so less body is exposed directly to the air. A bicycle with the body in prone position has been attempted, however, I think it's a very dangerous riding position, and I think it would be difficult to turn in tight spaces (in traffic).
• 

  arjunoids

  #-Link-Snipped-#
  
  #-Link-Snipped-#
  
  #-Link-Snipped-#
  
  tips to improve efficiency
  1. keep the air filter always clean. if necessary install a secondary.
  2. keep the tyre pressure to the maximum prescribed limit. (be careful, you may end up having a back pain over a period of time)
  3. use high octane petrol.
  4. keep the "idling" to as minimum as possible.
  5. check the the driving chain tension & also keep it well lubricated.
  6. do not, suddenly rise the accelerator.
  7. ride at optimum speed.
  8. service your bike regularly.
• 

  satanas

  Hi,
  
  does this include bike also?? bike and bicycle are not similar..
  
  
  well, we did a project on increasing safety in kids bicycles. its an automatic braking system, actually a speed limiting system. it prevents the kid from riding his/her bicycle at a higher speed than a preset speed (say 30km/h).. just some minor changes without affecting comfort and weight..
• 

  aprhockey

  To arjunoids: I think we're talking about two different things. We'd like this thread to stay on bicycles its quality of having a low environmental impact.
  
  About my idea of capturing body heat... i don't think it's really feasible. MIT is developing a device that uses the thermal energy the body creates, however, it can only capture 100 microwatts or so.
  
  Could magnets be of use in anyway?
• 

  satanas

  hmmm.. you want to the magnet to rotate the wheels?.
• 

  aprhockey

  well, magnets could easily be used to power lights on the bike using the concept of magnetic induction. If a couple magnets are placed on the spokes, when they pass an electric circuit it induces a current.
  
  Could the magnets be used to rotate the wheels? maybe if there were magnets around the rim and some placed on a fender so that as the magnets on the rim approached each magnet on the fender an attraction would accelerate the wheel forward. does this sound like it would work at all? I feel like this is trying to make a perpetual motion machine.
• 

  Vega

  Use of radium reflectors at back and front side of bicycle would enable other vehicles to see it. The light from vehicles will be reflected fitted to bicycle and help spotting bicyle in dark.
• 

  gaurav.bhorkar

  Vega

  Use of radium reflectors at back and front side of bicycle would enable other vehicles to see it. The light from vehicles will be reflected fitted to bicycle and help spotting bicyle in dark.

  I guess that is already available with latest bicycles.
• 

  Vega

  gaurav.bhorkar

  I guess that is already available with latest bicycles.

  Maybe! I don't know as I have not driven bicycle for long time.
• 

  2010mayan

  In the pedal crank we get the best mechanical advantage , only when the crank is at horizontal position. at other positions leg power is not utilised fully.
  
  A push down pedestal with rack & pinnion arrangement to convert downward motion in to rotary motion to drive the wheels thro chasin drive may result in a better mechanical advantage.
• 

  aprhockey

  @ 2010mayan: That may work. Do you mean instead of moving your legs in circular motion it would be more like pushing your feet alternately straight down? Would each foot move independently of the other? It would be interesting to look into it to see if it actually increased efficiency. It might be a bit tricky to design.
• 

  Ashraf HZ

  gohm

  How about adding power via using arms as well to drive the bicycle?

  Yeah, maximize power throughput. How about using our head too? The nodding motion can at least power the safety lights 😛
• 

  Vega

  2010mayan

  In the pedal crank we get the best mechanical advantage , only when the crank is at horizontal position. at other positions leg power is not utilised fully.
  
  A push down pedestal with rack & pinnion arrangement to convert downward motion in to rotary motion to drive the wheels thro chasin drive may result in a better mechanical advantage.

  Good idea! But I have couple of questions.
  
  In your design, how do you intend to bring the lever back to its top position? by leg pulling it upward or a spring or another power for it or other leg lever going downward will cause first one to come upward?
  
  What about its ergonomics?
  
  The existing circular motion gives good exercise to all leg muscles? What about this advantage in your design?
• 

  2010mayan

  Adding a spring to bring up the pedal may consume more power while pushing down. The two pedals are to be linked in such a way , when one pedal goes down other one will come on its own.
• 

  Vega

  2010mayan

  Adding a spring to bring up the pedal may consume more power while pushing down. The two pedals are to be linked in such a way , when one pedal goes down other one will come on its own.

  
  Yeah, something like crank, connecting rod and piston mechanism. Here there will be 2 pistons connected to two opposite end of crank by two connecting rods. Here pistons are peddles.
• 

  Salvatore Cosenza

  This is to inform You about the world-wide challenge which has been launched for the building of new human powered application that is going to break any human power (eg.: for climbing up-hill) and speed record.
  
  For reason of mere convenience, pedaling in HPAs and all the cycling world (up-right, standing position bicycles comprised, as well) will get its change, either for normal-dotated and disabled persons. Best advantage to Your Company isn't to delay upgrading, as least among other companies in the world.
  
  The present email gives me also, the opportunity to open to alliance with other companies (also envolved in outsourcing), Venture Capitalist and Business Angel for the constitution of multinational group aiming to replace all the bicycles in the world in the shortest time, as well as applying the patented system in all HPAs.
  
  Please give a glance to the following link:
  
  #-Link-Snipped-#
  
  Regards.
  
  P.S.: You may also check:
  
  System for transforming rectilinear motion to circular motion - COSENZA SALVATORE
• 

  emmawotson

  hey i also confused it is more complex. if you want the simple explitation then just visit the site:
  charusat.blogspot.com
• 

  Salvatore Cosenza

  emmawotson

  hey i also confused it is more complex. if you want the simple explitation then just visit the site:
  charusat.blogspot.com

  Sorry You haven’t understood the documentation of patent application I have filed (if You have taken the time to study it!). My patent counselor understood it, though they have acted some correction upon it.
  
  
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  When I get sponsor partners I might file-up new patent application more clear and concise, with other novelty characters.
  
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  P.S.: Email me to know my patent counselor address.
• 

  ramaseenu

  A cycle with bevel gear at gear axial inclination used for transmission of power from pedal to wheel .This may be a sustitute for chain sprocket mechanism.I may send detailed drawing if contacted at ramaseenu @ rediffmail.com.
• 

  Gurjap

  HA!! finally found the thread that led me to be a CEan in the first place.
  
  Anyway, I thought I had this brilliant idea of replacing the whole chain-drive set with a hydraulic power transmission system. It would have automatic gearing and power regeneration. I was going to use pedal power to run a pump, which would then pressurize a fluid to drive BOTH the rear and the front wheel by using a hydraulic motor on each of those (using hydraulics makes it easy to do that). It would be able to store power: when you pressed on the brakes, the pressurized fluid would be directed to a cylinder fitted with a heavy spring-loaded piston, which would be raised up, storing energy. When you released the brakes, this piston would pump back pressurized fluid back into the system.
  
  But as is wont to be with most of my ideas, someone already did it. And made a wikipedia page about it. Just awesome.
  
  But not a bad little project to do.... just for fun.
• 

  ISHAN TOPRE

  #-Link-Snipped-# This cannot be done to improve efficiency. The efficiency of cycle wont change. It will rather reduce with Hydraulic system installed.
• 

  Gurjap

  #-Link-Snipped-#.. really, will it? Fluid frictional losses are inherent in any fluid system, just as other kinds of friction losses are inherent in others. And I am regenerating lost braking power!
  
  Maybe I did not express myself too clearly. I did make a dwf file on Automation Studio, courtesy NITJ automation lab workstation. Here it is.
  
  https://docs.google.com/open?id=0B8XQjy5Ph3X4VnZodjVVVVdSaDJFZTFpZVJ5b2Y2Zw
• 

  ISHAN TOPRE

  Gurjap

  #-Link-Snipped-#

  #-Link-Snipped-# does that file need a particular format? It says not found #404 error
• 

  Gurjap

  hain? Not at all. Try copying the whole link and pasting it into the address bar.
  
  #-Link-Snipped-# Admin Update: Added image from the above mentioned source.
• 

  viky1147

  I don know whether this idea has been told already, though ill say here...
  
  Adding a proper Flywheel will reduce the human effort to some extent.. 👍
• 

  zaveri

  how about incorporating some hydraulic systems in a bicycle.
  
  it will be similar to the power steering systems in the automobile.
  
  a rotary hydraulic motor can be installed on the rear wheel and it will be connected to a gear pump. the input shaft of the gear pump will be provided with the crank pedals, which will then have to be powered only by the rider.
  
  this up to a certain extent will reduce the drivers effort.
  
  the pump and rotary actuator might increase the weight of the bike, but then there has to be a compromise somewhere.(this will be just another tradeoff)
• 

  zaveri

  sorry guys i see someone has already thought of this before
• 

  zaveri

  sorry guys but i see someone already thought of this before
• 

  Gurjap

  😀
  
  We still appreciate your contribution #-Link-Snipped-#.
• 

  zaveri

  the main concept governing the operation of bicycles is torque.
  
  if we increase the length of the crank pedals, then human effort can be reduced .
  
  but for that the machine will have to be redesigned because longer crank pedals may physically interfere with the ground.
  
  but the trade-off : only tall people will be able to ride it comfortably
• 

  Sarathkumar Chandrasekaran

  My perception:
  1) We had to the lightest material for the framework so that it helps in lowering the effort needed to drive the bicycle.
  2)Use of a better gearbox.(We all know that there has been many advancements in gearbox technologies for four wheeler and bikes but we didn't concentrate on bicycles).If we can manage to get the overdrive possible in bicycle, We can manage to get a better efficiency.
• 

  Jeffrey Arulraj

  Aluminum Bicycles by hero is one Cycle the whole world is waiting for
  
  This light metal has the potential to ravage the weight and also the cost of the bike. Once they are down the efficiency will be hiked
  
  Better drives are now available with at the least 6 gears for a decent geared cycles I think that itself gives the bicycle "The Cutting edge of Technology".
• 

  Anoop Mathew

  Jeffrey Samuel

  Aluminum Bicycles by hero is one Cycle the whole world is waiting for
  
  This light metal has the potential to ravage the weight and also the cost of the bike. Once they are down the efficiency will be hiked
  
  Better drives are now available with at the least 6 gears for a decent geared cycles I think that itself gives the bicycle "The Cutting edge of Technology".

  By aiming efficiency, you may not compromise with life-time of the Bicycle as well. Aluminium is light weight but is not very durable as anything aluminium tends to get fragile after a while due to rough usage.
  
  We've all used steel framed bicycles, but another sad part about them is that their maintenance cost tend to go upto 50% and above of the actual cost of the bicycle after a few years.
  
  P.S.: I have a Hercules Thriller MTB (Steel frame) which I bought for Rs3500 back in 2007, last year I spend Rs1500 to fix it fully - didn't change the rusting rims though, and gave it to my cousin brother.
  
  Now its back to badie because of the rough usage, and my cousin bought a new bicycle. I am infact in a dilemma whether I should shell another approx Rs2000 to fix the entire thing or just go for a new one to use for daily exercise.
  
  ~ This is exactly where we need to focus on efficiency: lifetime of a bicycle!
• 

  Jeffrey Arulraj

  Friend Making a bicycle in aluminium is itself a challenge You must know that a frame made completely out of aluminium can't support your body weight
  
  Hero Has made some modifications to the constituents of the material and made it durable for usage by people in all age groups.
  
  Next you pointed life time of a bicycle I have not seen it in Chennai streets. But rumors are that they are suited for race bikers and even for terrain bikers
  
  This will show that the bicycles are ready to handle extensive pressure. So their life time for common day to day use will be well in par with the existing ones
• 

  Anoop Mathew

  Jeffrey Samuel

  Friend Making a bicycle in aluminium is itself a challenge You must know that a frame made completely out of aluminium can't support your body weight

  Ofcourse it's not plain aluminium but it's an alloy. Just went visiting 3 cycle showrooms and I must say that this 'aluminum alloy' on most local models (Hero, and Hercules) are quite lightweight and has a plasticky feeling. I have to mention that those were for modes below Rs9000. Sadly everything is costly these days.
  
  

  Hero Has made some modifications to the constituents of the material and made it durable for usage by people in all age groups.

  Saw that, but I got to admit, maximum good looking and somewhat durable looking ones are those with gears. Call me old fashioned, but I don't know what is the exercise you get with a geared cycle?
  
  

  Next you pointed life time of a bicycle I have not seen it in Chennai streets. But rumors are that they are suited for race bikers and even for terrain bikers
  
  This will show that the bicycles are ready to handle extensive pressure. So their life time for common day to day use will be well in par with the existing ones

  Racing and all terrain models are more likely to get 'scrapped' after some few years of rough use - unless you go for the costly ones with insurance and stuff.
  
  P.S.: I was talking as a typical young city lifestyler who would like to use a bicycle for short commutes, and occasionally hit off-road and do some crazy driving. I highly give priority to looks and durability, owing to my past experiences with bicycles. Have checked various models of Rayleigh, Firefox, Hercules, Hero, and more, but some how I can't decide which one I should go for as the models which make sense to buy taking into account my age and usage are well above Rs9000. I'd appreciate if anyone here can help me out with a model worth rough using, neglecting for a while and hopefully keeping for quite some years.
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  Jeffrey Arulraj

  Nice to hear the complete break down of my answer Mate with less than INR500 your geared bike turns into a completely gearless old fashion bike you need
  
  Other features are cool/
  
  Last but not the least sorry mate design and market accceptance of aluminium bicycles are less so prices will be really high
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  Apurva Patil

  ??? How funny.

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  Ramani Aswath

  The only vehicle that I ever ‘drove’ was a second hand Humber bicycle that bought for ₹200 in 1962. Used it till 1975 and passed it on to my brother in law, who in turn passed it on to his younger brother, who gave it to the landlord’s grandson. I lost track after that. I read an article that said that a man on a bicycle was the most energy efficient means of transport of mass. The article even took into account the energy consumed by galaxies down to insects. This article is untraceable (by me at least). Graphene reinforced structural material is available ( at a cost) Lightweight engineering plastics (quite expensive) can be used for transmission. Aerodynamics may add a fraction of speed in races. Irrelevant for ordinary speeds what we are considering.

  A non geared regular bike is just fine using lightweight materials. We have to remember that the human payload is the larger mass. Even if the bike has zero weight, the rider has still to be moved.

  Here is an interesting article:

  How the bicycle beats evolution and why Steve Jobs was so taken with this fact | Bike Boom