What exactly is bicycle torque and how do I adjust it?
816960
OK, there are a couple of reasons that your bike might be creaking, some worse than others:\n\n1) If the bike makes the noise only as you are pushing down on the pedals, chances are the crank arms are loose. These need to be tightened to a specific torque so I recommend a bike shop visit;\n\n2) If the bike creaks when you are seated, it may be because the saddle or seatpost is loose. Make sure the saddle is tight on the seatpost, then REMOVE the post from the frame, coat the inside of the seat tube (the frame tube where the seat post fits), then reinstall the seat post. If you overtighten the seatpost in the frame you may damage the frame, so be careful;\n\n3) If the bike creaks when you put a lot of stress on the handlebars, slide the bars out from the stem and lubricate between bar and stem as with the seatpost. If you have a standard quill stem, also remove the stem from the fork and lubricate with grease inside the fork tube (steerer). Should you have a threadless steerer I recommend that you, again, take it to a bike shop just to be sure everything is cool; \n\n4) If your frame is aluminum, it is beginning to fail. Unlike steel, aluminum will eventually fail just from regular riding. Occasionally this failure is pretty spectacular and is called "Sudden Catastrophic Failure". If you have a high end bike (perhaps $1500 or more) and the frame is aluminum, sometimes they creak from the day they are new.
819851
I'm not familiar with the brand. Most adjustments are on the handlebars by the throttle. If it is a chinese brand then good luck and shame on you.
1137210
I think the freewheel removing tool looks like a piece of metal with a bike chain attached. The chain is bout 12" long. If you already have the cogs, it's easy enough, you may just need a vice.\nI bet you could find the cogs easy enough. Try going to a pro bike shop and asking them if they have any 5 speed freewheels. or cogs hiding in a storeroom. ( I got a good deal on a campy record hub for a set of race wheels for my older bike) or check ebay. If you had 2 freewheels, you could just have one set up like a corn cob and one set up for big hills. It's a pain to keep changing cogs on those old sets.\nI'm not sure you can go with a 6 or bigger freewheel. Your wheel may have to be dished differently.
960317
Technically your bike has 21 gears--the number of rings on the front times the number of rings on your cassette in the back.  However, you don't really have 21 usable different gears.  This is because:\n\n1) Depending on how many teeth are on your chainrings (front rings, you have 3) and your cassette (7 rings on back), you may have some gears that repeat.  It is all about the ratio between the front ring and the back ring the chain is on.  For example, let's say your middle front ring has 38 teeth and one of the rings on your cassette in the back has 19 teeth, you have a ratio of 2 to 1 when your chain is on these two rings.  If your smallest ring in the front is 28 teeth and your smallest ring in the back is 14, you again have a ratio of 2 to 1, so these gears are actually the same.  \n\n2) There are also certain gears you should not use.  You should avoid cross-chaining--being in smallest ring in front (closest to the bike, on the inside) and the smallest ring in back (farthest away from the bike) or largest in front (farthest away from bike) and largest in back (closest to the bike).  Either of these gears, or close to them, puts a lot of stress on your chain because it torques it sideways.  This will cause additional wear on the chain and shorten the life of it.  Most bikes will allow you to do this because the chain is put at a length to allow for it, but it will also likely cause your chain to rub somewhere and also possibly make your bike not stay in gear very well.  \n\nHowever, these days, rather than multiplying the number of front and back rings to get speeds, bikes are now often referred to by the number of rings on the chain ring and cassette separately.  You ride a 3 by 7 (3x7).  A double road bike with a 10 speed cassette (typical of today's high end road bike) is a 2x10.  A more touring oriented road bike often has a triple chainring and is likely to be a 3x9 or 3x10.  A fairly typical mountain bike is a 3x9, but there are a lot of 2x9 or 3x8s out there too.
723260
Question 1:\n\nTorque is a force applied at a distance,\nT = F * r\nWhere T is the torque, F is the force, and r is the radius the force is applied away from the center or rotation.\n\nT = 40 Newtons * .15 meters = 6 Newton meters\n\nA torque causes an angular acceration,\nT = alpha * I\nwhere T is the torque,  alpha is the angular acceleration, and I is the rotational inertia ("moment of inertia").\n\nAn angular acceleration relates to a linear acceleration,\nalpha = a / R\nwhere alpha is the angular acceleration, a is the linear acceleration, and R is the radius of rotation (the wheel's radius in this case).\n\nThe linear acceleration can be found by finding the change in linear velocity with respect to time,\na = delta v / delta t\na = 2.25 m/s / 3 s = .75 m/s^2\n\nalpha = .75 m/s^2 / .5 meters = 1.5 radians per second^2\n\nT = alpha * I \n--> I = T / alpha\nI = 6 Nm / 1.5 rad/s^2 = 4 kg m^2\n \nDo your own homework next time (like on question 2).\nhttp://sln.fi.edu/qa97/spotlight3/spotlight3.html
455111
The cage length affects capacity. Capacity is defined as the difference between the number of teeth on the largest and smallest cogs, added to the difference between the number of teeth on the big chainring and the small chainring. Long cage rear derailleurs have a high capacity, and can therefore handle a very wide range drivetrain. Short cage rear derailleurs are more limited in their capacity, working best on a drivetrain with closer gearing.\n\nShorter cage rear derailleurs take up less chain slack than a long cage rear derailleur. The chain is held more snugly, which can result in smoother, more precise shifting. However, longer cage rear derailleurs are capable of taking up more chain slack than a short cage rear derailleur, allowing you to run a wider range drivetrain than would be possible with a short cage rear derailleur.\n\nFor road bikes, your choice is fairly straightforward. If you plan to use a double crankset, stick to a short cage unit. For triple cranksets, you'll want to use a longer cage rear derailleur to handle the increased chain wrap necessitated by the wider range drivetrain.\n\nOn a mountain bike, your choice is slightly more difficult. Less experienced riders, or riders who ride frequently in steep terrain should probably stick to a long cage rear derailleur. This, combined with proper chain length, will allow the bike to be safely shifted into every gear on the bike. Racers might appreciate the lighter weight and slight shifting improvement a short cage rear derailleur offers. However, these benefits come with a tradeoff - because of the decreased capacity a short or medium cage rear derailleur offers, it may not be possible to safely use the small chainring in tandem with the smallest cogs. (The derailleur simply can't take up enough slack in the chain)\n\nFor mountain bikes, when in doubt, choose a long cage rear derailleur, unless you are certain you understand the limitations of a short/medium cage derailleur.
697205
Yes, but to a smaller degree than when on the ground.\n\nThe inertia  and the weight of the wheel will have an effect as you change speed and gears.  This is not real "rolling resistance" but has a similar, but smaller effect.\n\nIf you are on a bike stand and rotate the pedals at 60rpm in the lowest (speed) gear, then change to the highest gear, you will see more   "resistance" until the wheel is at its new higher speed.  Then you will see some resistance to maintaining that speed and cadence.  This will be more than resistance in the lowest gear, and more pronounced the heavier the rear wheel.
1110273
Bicycles these days have things like index shifting, this develpment has made cycling much eazer for the beginer. Back in the old days, "the 70's", I had to learn to shift by feel. This led to a lot of looking down and back, while working the shifter levers," once rode head on into a parked car doing that, even the people who owned the car were laughing". So you have the advantage of this wonderful index shifting. When approaching a hill down shift as you feel your legs begin to bog down, with index shifting you can down shift 1 gear at a time untill you reach the top of the hill. As you become stronger you'll down shift less. What you want to do is keep a steady cadence," RPM of the cranks", and use the different gear ratios to fit the terrain.
1037503
Check out this photo for proper chain configuration-\n\nhttp://152.10.254.216/images/Shimano_XTR_derailleur0_DSC.jpg
288970
how to change it depends on your bike. when changing speeds you MUST be pedaling. if you are not it messes up the gears (i learned that the hard way).  you want to use speed one when you are going uphill or the going is harder.  the high speeds are used when the land is flat and smooth or when you are going downhill. i hope this helps!
964921
All bicyles are geared, unless you have a one to one ratio like a penny farthing or a big wheel (which is a tricycle, so ignore that lol!).\n\nEven if it is fixed gears/ single speed, the bicylce still has a gearing because that is what lets you pedal one rotation with your legs but do more than one rottion with the wheel.  A non-geared bicylce would mean (if you had a normal sized wheel) having to pedal like a gerbil at speeds higher than three miles an hour, and if you have a massive wheel so you don;t have to pedal like crazy to go three miles an hour (like a penny farthing), then you have trouble starting the damn thing, plus the trouble of having a massive wheel to climb on to every time you want to ride/ fall off of when you crash.\n\nSo, I guess you mean a bicylce with more than one speed gearing.  Well, it is like riding any bicycle.  You get on the bike, then pedal and steer by leaning and using your arms to turn the bars slightly.  You brake using the levers on the handlebars, or by pedalling back if you have a coaster brake.  if you don't have any brakes, stick your feet in the wheels, but be careful with the front as footjamming brings the back of the cike up and may throw you off.\n\nIn terms of changin gears, you will have some sort of gear shifting mechanism on the bars.  You will have one for the front rings and one for the rear cassette.  Lower gears are for riding up hill, higher gears for riding down hill.\n\nTo change gears, you should be pedaling.  Shiftin gears when not pedalling can confuse the system and mean the chain jumps when you do start to pedal.  Also, change up or down one gear at a time, don;t jump a whole raft of them in one shift for the same reason.\n\nSo, you pedal, and depending on what mechanism you have, you either twist your grip to the desired gear, or you flick a little switch/ lever that changes gear for you.\n\nhttp://www.westernveil.com/
981260
well you don't NEED to change out your fork, you can do a few things. If your fork has air assist you can lower your psi, also look into getting new springs and a lighter weight oil. I suggest going to you local bike shop and tell them the problem your dealing with and see what they can do to help you...worst case buy a new fork that can be fully tuned to get the feel your looking for.
674183
I have been cycling for about 15 years. The best way to train for cycling is to be a 'spinner' not a 'grinder'. A spinner is someone who is constantly pedaling. The key to being a spinner (i have found) is train your body/mind to downshift BEFORE you need it. If you are pedalling and you think that there is 'too much resistance' at the pedal (aka--that the pedal is getting hard to push) then you are downshifting too late. Lance Armstrong is a excellent example of a spinner. \nA grinder is someone who uses a higher gear that generates a lot of power, but generally that uses a lot more energy from pushing a higher gear.\n\nMy personal favorite way to keep my spinning technique up is to use a computer that measures your cadence. Normal bicycle computers mount a sensor on your front tire and fork. This measures how fast you go, but you could ride a down a mountain at 25 mph without pedalling much--and that would not necessarily be a good overall training indicator. A computer with cadence mounts on your crank and it measures crank rpm. If money is no object, you can get gear that measures the amount of watts you are producing. This can get pretty pricy though. \n\nHope this helps you out.\n\nIf you have any more questions (need gear recommendations or anything). Feel free to email me at whostolemymojo at yahoo . com\n\n=)\n\nOh and to answer your original question. I watch a lot of cycling on t.v. myself. Most riders maintain a constant (fairly constant) pedal cadence. This definitely varies when they are riding in a pack as drafting or obstacles (riders in front and/or on both sides of you) take place. You might have to coast/stop your cadence momentarily in those circumstances. Also, weather, terrain--down a steep mountain grade, curves, etc can affect you as well. Watch more racing and see how often most guys pedal. You will notice it is almost always non-stop when there is no outside factors hindering their progress. The key to cycling is to go as fast as you can while expending as little energy in the process--hence drafting is a great way to conserve energy for the sprint at the end of a race.\nUnfortunately, if you are training for triathlons, you will not have the good fortune of drafting--triathlons have many rules prohibiting drafting.\n\nGood luck!
1039588
Nothing to do with angular momentum. \n\nIf you weight the rims of the wheels of a bike to increase the angular momentum so that the wheels behave like a gyroscope (bike wheels are really light usually), the bike becomes almost impossible to ride.\n\nA bike stays upright because the centre of gravity at the front wheel is slightly behind where the wheel touches the ground (the bike forks bend forward). Because of this, if the bike tips to the right the front wheel turns to the left and vice versa. \n\nIf the bike is stationary this does not help a lot.\n\nBut if it is moving forward this tends to steer the bike out of toppling in the direction of lean, and this helps you to balance the bike ( a bike with no rider always falls over - its your sense of balance that keeps it upright).\n\nThe fast the bike goes, the more pronounced the self correcting steering is.\n\nPS bikes have been made with the forks bent backwards so that the self steering is in the direction of lean, so exaggerating a loss of balance -it is hysterical to see someone try to ride this sort of bike
964946
You probably need to repost and clarify a few things-  do you mean crankset (which is the front three gears) or cassette (which is the gearing on the rear wheel, usually 7 - 9 speeds)? Also, by rear mech, do you mean derailleur, or rear cassette?\n\nI can tell you this - when Shimano moved from 8 to 9 speeds they changed the chain, so a 9 speed crankset and an 8 speed cassette might be problematic.\n\nIf you are only worried about your rear derailleur, then you should not have much of a problem - just set your adjustment screws correctly and go.
112586
What they are setting their bikes on is a trainer.  I have a bike set up on one right next to me.  Trainers vary in price.  You can check several of the online bike stores and find them on sale at this time of year.\n\nIdea is simple.  Put your back wheel in a stand so it is off the ground.  You have a resistance unit that rubs against the tire.  The resistance unit allows you to adjust the amount of the resistance you can make it harder or easier.  The biggest difference between trainer is how the resistance unit acheives its resistance. The more expensive units are generally quieter.  The cheaper units use wind  and are very noisy.
284019
Your derailer needs adjusting, you can find how to do this on lOAds of cycling web pages.\nBasically you have to adjust the two screws so you can get the biggest and smallest gears then you need to adjust the cable tension to be able to select the gear straight away.\n\nTo do this put the gear leaver in the second SMALLEST gear and adjust the cable tension untill the derailer is in that gear. Then slightly adjust the cable adjuster to it changes smoothly up and down. \nNow recheck the top and bottom limit screws to make sure the chain does not run off the biggest or smallest cogs.\nAny probs let me know.