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18

As (almost) always, the great Sheldon Brown has covered this particular topic. Standing while Cycling To Sit or to Stand? It is my belief that a great many cyclists stand up to pedal much more often than they should. I've often said: "If you find yourself standing to accelerate, on level ground, it is a sign that your gear is too high or that ...


13

You have a double front, right? The usual advice is to not shift into the highest 3 gears in the rear cassette when in front the chain is on the large chainring, and to not shift into the smallest 3 cogs, when the chain in front is on the small chainring. This prevents 'cross-chaining', which wears the chain fast, produces noise and difficult shifting. ...


11

http://www.landriderbikes.com They were very heavily advertised several years ago but currently they seem to show up more on craigslist than on TV.


11

If you can, with the chain in one of the middle cogs in the back, shift to each of the front chain rings then your front derailleur is likely in proper alignment and adjustment. This question and answer cover how to adjust the derailleur if you want to learn how to do it yourself. What you are describing, shifting to small ring in front and small cog in ...


9

Learning some better shifting technique may solve this. It also could be that, despite your best efforts, the derailers are out of alignment. Two questions: Is the chain falling off on the front chainring or on the rear cogs? If so, is it happening on the inside or outside? (If it's happening in the rear and the chain is hitting the spokes, this can be ...


9

Trek had a bicycle a few years ago named "Lime" which had 3 speed automatic gearing. I don't think it sold well. It used a gearing system called "Coasting" that was created by Shimano and actually controlled by a computer chip from signals from the front hub. "A dynamo is fitted on the front hub that gauges the revolutions of the wheel. It sends this ...


9

There isn't really any reason you can't stand while pedaling. If your drive train is not adjusted properly then they will experience skipping or mis-shifting. That's an entirely separate issue from being able to stand up and pedal.


9

I agree with Hicks sentiment that the crank "giving" is more likely due to worn parts or misalignment. The crank would have to flex a lot to actually be responsible for ghost shifting, which would make it incredibly poor quality. Sheldon's article strikes me as cursory for "When Should You Stand"... Assuming you have the gearing for whatever you're riding ...


8

I have ridden one - it used weights thrown out by centrifugal force and springs to move the derailleur in and out. Horrible is all I can say. Maybe it was me not being used to it, but things like not being in the gear you left it in, and less than smooth changes - which you have not idea when they are going to happen, especially under power. The only ...


8

Not using the upper and lower gears is a very effective solution. Stupid, but effective. Traditionally one would simply use the limit screws (at the rear derailleur, often marked L(ow) and H(igh)). Shift to the lowest/highest gear (front and rear) and tighten the screw so that it only allows the mech to move ever so slightly over the edge of the ...


7

The B-screw controls the body angle of the derailleur. It pulls the pulleys away from the sprockets, so you don't rub against them. If you set it in the largest rear cog (as you should), when you're adequately clear, you don't have rubbing. Its a somewhat insensitive adjustment once you clear the cogs, but the closer you are to the loosest screw value ...


6

Since it only happens when you stand I would say it is definitely a combination of a worn chain and worn chainring, and nothing to do with shifters or derailleurs. As a chain wears, it 'stretches', meaning the distance between the pins in the chain grows. This is a result of the side plates wearing into the pin. Once the chain starts to 'stretch', it starts ...


6

Sad to say, not worth the effort! However, if you are a bulk user of cable outer then you can invest in a big reel of the stuff (obviously genuine Shimano) and some Shimano cable cutters (TL-CT-10). Broken link: http://www.madison.co.uk/productinfo.aspx?catref=6Y1+9801 Possible replacements https://www.google.com/search?q=Shimano+cable+cutters ...


6

3 basic tips Try to be predictive in your shifting. Don't wait until you really need the next lower gear to change gears. Try to do it before your cadence drops to where you're mashing on the pedals Ease up on the pedals when shifting. If you missed on the first tip, then let up on the mashing very briefly during the downshift. This will aid the chain in ...


6

I would suggest temperature change may be affecting the cable housing dimensions, which in turn affects the cable tension and therefore the dérailleur settings. I have been noticing this happening to myself this fall, especially switching to a bike with full length housing and 10 speeds on the rear dérailleur. With the large daily temperature changes in ...


6

Its likely that your bad shifting is due to messed up cables or a misadjusted derailleur. You can either cut the cable crimp off at the end of the cable with a pair of pliers, or pull it off with a pair of pliers. As for replacing the cable housing, you can either get your bike shop to cut a piece of housing of the right length by taking your old housing ...


5

There have been attempts over the years, but never particularly successful. One I recall used a 5-speed rear hub that was shifted by weights on the spokes, similar to a centrifugal governor. I expect that, with the new electric shifters, there will be some new attempts at it in the next year or two. With a computer it should be possible to be reasonably ...


5

There's the Nuvinci Harmony http://www.fallbrooktech.com/cycling/harmony It uses the Nuvinci N360 CVP hub, which is a continuously variable transmission, meaning there are no shift points. The Harmony controller changes the ratio based on cadence, or it can be adjusted manually. http://en.wikipedia.org/wiki/NuVinci_Continuously_Variable_Transmission


5

It sounds as if you adjusted the barrel adjuster out too far, the last time you adjusted it, and damaged the threads on the adjuster. When the shop cleans and lubes it, it is fine for a few days, and then gets stuck again, because the threads are cross threaded or stripped. If the damage is relatively minor, it can act normal until it is under a little ...


5

I would have started by noting which gear (front or rear) is slipping and adjusting the tension on the corresponding shifter/derailer to bring it closer to correct adjustment. A rule of thumb is, make the adjustment and if it gets worse then you are going the wrong way :-) If the shop changed your chain did they also change the cassette (rear gears). The ...


5

Crossing chaining hasn't been any problem at all since the invention of bushless chains 20+ years ago and wasn't even a real problem back in the ancient days. It's a persistent myth that just won't die... Your bike should leave the shop capable of shifting into any combo of gears possible and riding any amount of time you like in that gear. At most I would ...


5

In reality the derailleur doesn't care what the tooth count difference is between gears. The shifter simply moves the derailleur towards or away from the wheel. This causes the chain to be misaligned with the current gear and move to the selected gear.


5

Those are just gear cables, you will need to buy brake cables and outers. Good on you for building it yourself, it's definitely do-able with a modicum of skill and even with limited experience. But... there's quite a few things you can do slightly wrong that will make the bike unsafe to ride. I think it would be good to have someone check over the bike ...


4

I would bet for the chain having rusted, leaving some links "locked" and not turning free between each other. Also, if rust built over the sprocket's teeth surface, it can cause the chain to skip under pedal load, bacause the chain doesn't engage properly. I am telling you this because my damn lovely(#@%) cat pissed the cog cluster of one of my bikes, and ...


4

Assuming it's not been used it probably needs a touch of lube and some adjustment. If your friend only rode it for a month he probably didn't even get the bedding in service done on it. New cables on a bike normally bed in after a little while (time depends on use) and so things go out of line fairly quickly initially which is why bike shops normally do ...


4

It sounds like you have accidently mixed up the cables and routed the front dérailleur cable to the rear shifter and vice versa. You can change them so that the front shifter goes to the front dérailleur pretty easily. Just swap them at the shifters.


4

Since everything else is working, this is when I suspect hanger alignment. Where the rear derailleur bolts on to the bike, just under the quick release/axle, is a relatively fragile piece of metal. They get bent if the derailleur is bumped hard, and for that reason are often replaceable parts. The problem is sufficiently common that there's a tool made ...


4

First off, of course, lubricate the cables and assure that the derailers are properly adjusted. After that, make sure you're not cross-chaining too much when shifting up -- you should have your rear near the outer cog before up-shifting the front, so that the angle of the chain isn't fighting you. Also, understand that you must let up a hair on the cranks ...


4

First disconnect the cable to rear derailleur and using your hand push the derailleur towards the spokes and then release it. Do you feel any binding? If so, something is wrong with your derailleur. With the rear derailleur cable still disconnected, grab hold of the cable and slide it through the housings. Is it catching on anything? Some resistance is ...


4

The following links will show you how to adjust a derailleur: http://sheldonbrown.com/derailer-adjustment.html http://www.parktool.com/blog/repair-help/rear-derailler-adjustments-derailleur Note that cables and derailleurs do need replacing from time to time and they do need occasional adjustment, but try to follow one of the derailleur adjustment ...



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