New answers tagged

2

Almost certainly the gear cable has come off the hub at the point where it's adjustable. Without knowing which make and model of hub you have I can't be more specific than that. If the bike is new take it back and get them to show you how to fix it, or at the very least fix it for you. If not, work out what hub you have (the manufacturer plus five speed ...


3

I beg to differ! I spy more cables hiding in the carpet If you have two pairs of cables, the thicker ones are for the brakes (thicker=stronger in this case) So there will be some lengths of housing to match each pair, in two sizes to suit the cables. The lengths of brake housing will be one short (front brake) and one long (rear brake). You can run the ...


1

You're trying to pull more cable through but the shifter is already in min gear after one click, while the derailleur is not. The shifter needs to be in the correct gear (smallest cog) when you install the cable. So when the cable is un-done, you should repeatedly press the thumb shifter while pulling the cable until all the tension is released. Then ...


3

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 ...


1

52 tooth chainring, no problem but the difference is kind of small and not necessarily worth the trouble. 10 speed cassette, for road bikes the same derailleur works but you need narrower chain and shifter with 10 speed indexing.


1

Think of the problem from the other perspective. The designer of the cassette knows how much the derailleur will move the chain laterally - nearly constant each shift. That's all the derailleur really does. The designer can therefore design the profile of the cassette teeth and the position of each cog 'clockwise' relative to the next one to enable good ...


-2

I think it is a good idea since it gives the rider a choice between close ratio and skipping gears. Perhaps a special shifter that has 2 rings, one shifts every gear and the other shifts to every other gear (such as cogs 1,3,5,7...). Then the rider can start in a desired low gear and perhaps quickly go up thru the gears 2 at a time until the midrange gears ...


-2

I say it is both possible and practical. If someone really wants the crawler gear then this is a way to get it without having to resort to other methods such as a double gear reduction (chainring and cogs being only 1 reduction then adding some other one). If someone ever tries this then please report back. I would love to have a bike with this isolated ...


-1

I assume the mech hanger is aluminium, as normal. Aluminium is much less able to handle fatigue caused by this kind of bending than steel, I would advise strongly against trying to bend it back into shape. The only reason your bike even has this part is so that you can install a new one cheaply when you damage it in this way. Without it an aluminium frame ...


3

I don't think so, as long as you have correct cable housing and ferrules where you need them, there's no problem having multiple barrel adjusters. If you know how to use them then there's no downside to having three in my opinion. Try it and let us know!


1

If there is a strong resistance. My guess is that you have a limit screw preventing the fron derailleur shifting to bigger chainring. Check limit screw Check if front derailleur can move freely (unscrew both limit screw and pull the cable to see if front derailleur move). Sometimes front derailleur corrodes to the point that it cannot be moved.


1

I have never seen such a design. As others have mentioned, the described design would be difficult to make work as you would need to switch the gears and if you didn't want it fixed you'd need a freewheel that engages backwards. However, you may be interested in the retro-direct (https://en.wikipedia.org/wiki/Retro-direct). The retro-direct has two ...


3

Answer: No. But you could make design and make one. You'd have to have some creative way to safely disengage one of the chains, and let the higher gear click away on its freewheel. Try sketching up a drawing and posting it for feedback. Not just a description in words, an initial diagram.


1

In short, no. Bad idea. But if you get lucky a couple of times, yes, it could work like you want. 8spd freewheels cost about the same as 7spds, so not much risk in 'going for it' and failing. Realistically, stick to 7 spd and upgrade the RD for the extra capacity to deal with the big cog if you must... but I'd try it out first, they usually ship long cage ...


-1

Best solution is going to be to replace the hangar and the rear Derailer. However, you can take the hangar off and use a vise to get it flat. Clean it and the frame around that area to keep dirt from interfering with the attachment. Use blue loctite (formula 242) on the fasteners and a light coating of grease on the flat areas to keep dirt out. For the ...


-1

It looks like both the Hangar and the attachment from the rear mech to the hangar are bent? You could try to straighten yourself with pliers or a small wrench but I would suggest a visit to the LBS who will use a Hangar Alignment Tool http://www.parktool.com/product/derailleur-hanger-alignment-gauge-dag-2-2?category=Frame%20&%20Fork With a bent hangar ...


1

Yes - 24 to 34 is a big jump, but in practice it just takes another half to one second to complete the shift. Also helps that you'll be riding relatively slowly by the time you want that gear, probably ~10 km/h and likely half that speed. A freewheel is not cheap but is not ridiculously expensive either. You should buy one, fit it, and try it out.


1

Your double shift (when you change chain rings) would have to be perfect. You'd have no power until you'd shifted both front and rear. This would be especially bad changing down for a hill. The front derailleur would have a very hard job to do. I'm not sure current designs could be extrapolated to something that could handle a 20+ tooth difference and a ...


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.


0

This is sort of irrelevant: If you spend a lot of time on the bike you have to change the cassette and chain fairly regularly if you want to maintain good gear switches. In this situation a well maintained chain will need replacing because of chain stretch way before it will need replacing because of winter conditions. In the situation of "run the ...


0

Front: Granny = 1, mid = 2, big ring = 3. Rear: Biggest ring = 1, smallest ring = 8. I would probably switch up like so (front gear,rear gear): 1,1 1,2 1,3 1,4 then either 1,5 1,6 if I won't need to go to middle ring any time soon or 2,3 2,4 if I will. If I know I am going to be in mid ring from a certain point I might switch from 1,3 to 2,2 instead. ...


3

At first glance I see the problem you are having . Those are NOT friction shifters . They are positron shifters . Research Shimano Positron Shifters for a more definitive explanation This was Shimano's earlier attempt at an indexed gear system. Also known as "Positive Pre-Select" or PPS. The main differences are that the indexing is in the deraileur ...


8

Yes. Barrel adjusters are reusable. More useful for the front mech which doesn't have any on-the-fly adjustment. And useful for the rear mech for quick adjustment without having to get out of the saddle.


0

Here's an image of your derailleur showing the return spring attached to the slot furthest from the top of the cage https://c1.staticflickr.com/9/8111/8602860708_0e4e4a50ef_b.jpg To answer your second question, seems reasonable to replace the double nut on the outside of the fork end with a single nut.


5

Less complexity (less things to go wrong and set-up.) No chance of shifting front and back gears simultaneously leading to loss of chain tension and resulting in chain drop. Less weight. Optional chain guides. More clearance (in most practical applications) Furthermore: 3x7 is very old. 1x11 is pretty new. Materials and technologies have evolved ...


1

This actually describes basically exactly the way my bike is set up. I have 52x42x30 chainrings with a 12-23 cassette. The 30x23 is plenty easy for the hills that I tackle, and the 52x12 is such a hard gear that I rarely ever need to use it. And the spaces between cogs are only 1 or 2 teeth, making the steps between the gears quite small. The reason that ...


1

One important advantage of 1x11 gearing is the improved clearance of the front chainring. In technical riding, the largest cog would strike stones as you are riding over them. This happened to me all the time until I removed it (I have 2x10 now). Another advantage is reduced weight and mechanical complexity - if you have just one front cog, you don't need a ...


4

Ideal differences are generally thought of to be around 15%. Changes in excess of 20% make it difficult to select a proper gear for spinning based on varied conditions. Changes of less than 10% are so slight that they will almost unnoticeable to most unskilled riders and even some skilled riders. You make an assumptions about the purpose of gearing on a ...


17

1:1 and similar ratios are considered bad in automotive gearboxes. If there is one bad tooth it will soon take others with it, if it is always meshing with the same teeth. Automotive gearboxes tend to use coprime ratios (where the 2 gears have no common multiple) to avoid this. There really isn't a similar issue on a bike. I suppose it might be a good idea ...


2

There is very little to no side to side stress in the wheel. The side to flex is from the bar to the crank via the frame and headset. My single speed mounting bike is 32 x 16 so it gets repeated stress and zero problem. 32 x 16 is a pretty common SS mountain set up. Some SS cyclocross racers go with with that. In loose gravel/dirt at my max torque if the ...


8

I think that 1:1 is only a problem if you forget that you will end up coasting a bit. Any amount of coasting, or even switching gears for a few seconds will end up making a different part or the wheel undergo the stress. Unless you are climbing for a long period of time without any changes in gradient that would require changing gears, then I really don't ...


6

I have a half-decent hybrid with the option of 28/28 from stock, and there are places where I used to use it quite a lot with no trouble. More importantly though, I'm not sure what you think is special about 1:1 gearing. The load is spread over a good (large) number of teeth front and rear. There are no sharp bends or cross-chaining effects to worry about. ...


-1

I have a cheap Walmart mountain bike and my 2nd lowest gear is also exactly 1:1 (24/24). Why would you avoid a gear that is very useful? I am setting up my bike so it has multiple underdrive gears instead of just 1 so I can better control my speed and cadence in low bike speed situations. Having just 1 low gear is not as good as having several. If all ...


1

You aren't going to be able to get those rivets out and replace the smallest chainring; it's not going to happen. Chainrings and the holes for the bolts are designed for tight tolerances and you'll never get it back together in a functional manner. Do I think you should try? Absolutely.


4

Everything on a bike is a tradeoff between efficiency and weight and complexity and cost. If you imagine the simplest drive ratio which is 1:1 then the cog and chainwheel could be any size up to the rim size. and down to the mechanically smallest possible around the axle, perhaps 4 or 5 tooth? Why not a really big chainring and cog on the simple bike? ...


1

You could do this for the front with a Mountain Tamer Quad (which is an adapter which turns a triple into a quad) and an appropriately chosen front derailleur. The chainline issues become more severe than they do with a triple. For the rear, you could use a 12 speed internal gear hub (Sachs Elan) or go up to 14 with a Rohloff Speedhub with a chain ...


-1

Here is what I have for a progressive 3x9 setup using all 3 chainrings and all 9 cogs but using only 3 cogs per chainring. chainrings (20,30,40) cogs : (36,28,22,25,20,16,18,15,12) Ratios would then be: 20/36 = 0.56 20/28 = 0.71 20/22 = 0.91 30/25 = 1.20 30/20 = 1.50 30/16 = 1.88 40/18 = 2.22 40/15 = 2.67 40/12 = 3.33 Overall spread is 6:1 between ...


1

If you really want that wide a ratio, the widest ratio chainset combined with the widest ratio cassette commercially available would get you very close. There are crank sets that can take chain rings from 22 to 50 teeth (finding a front derailleur that could do this range might be hard), and an 11-40 cassette. Cross-chaining would be a bad thing given how ...


5

Yes, you could do this and done as you describe I think you'd end up with as many ratios as rear cogs. Someone once made a single-shifter derailleur system that moved both derailleurs from one shifter (using two cables) and "IXOV" has apparently started doing that again with the "Synchrobox" but all I can find are press releases, not even a company ...


3

The closest to that is the Sachs DD3 "dual drive" hubs that are a 3 speed IGH with a standard cassette mount, available in 8,9 or 10 speed cassette versions. According to this site the ratios in the hub are 0.73,1,1.36 giving 1.86 between high and low gears. That's wider than a double chainring setup but narrower than most triples (a 20/30/40T triple has a ...


4

It would most likely not work without a bunch of expensive finagling. Most inexpensive cassettes come on carriers, meaning removing individual gears is not really that possible. You can still buy individual gears, but they are a more specialty item and very expensive. After you messed with all that, you would likely find that the lower gears tore through ...


6

Seems like a lot of work for little gain. You'd be able to lighten by the weight of 7 cogs, but the shifting action will suffer. My early megarange was quite bad at the last change, which was 26 or 27 up to 34 You'll also need to install 7 cogs worth of spacers to hold the remaining three in a fixed place on the freehub. And I politely challenge the "I ...


7

Depends on your budget, your requirements, and your mechanical aptitude. Plus how far down the slippery slope of knock-on upgrades you want to do on a BSO bike. Since the crank is riveted together, its unlikely to accept any bolt-on replacement chainrings. Though its possible the makers used rivets instead of bolts but used normal bolt chainrings. You'll ...


4

Short answer: you multiply the number of front chainrings by the number of cogs at the back. That bike with two chainrings and 11 cogs on the cassette has 2x11 gears = 22, rather than just 11. Bike Gears Explained has lots more detail and this diagram: You can see that for each of the three chainrings every cog on the back can be used. In this case that ...


12

I think the terms used here are a bit confused. Rather than saying that a road bike has 22 "gears", you should be saying that it has 22 "speeds" (or more correctly, as pointed out in the comments, "gear ratios" is the technically correct most accurate term (when people say 'gear', they are using it as short for 'gear ratios')). Even that can be a bit ...


5

It's pretty normal for a bicycle with a freewheel/freehub to turn the wheel backwards a little bit when pedaling backwards a bit (i.e. if you turn the pedals backwards pretty quickly, you get some very slow backwards turning of the wheel) when the bike is in a stand/lifted in the air. You can sometimes get rid of this by servicing/replacing the ...


0

Cycling in a big gear is a very common training session for cyclists. Big gear & low cadence seated hill climbs are sessions I have done in the past. The idea is to build muscle and consequently strength. This on its own is not ideal - since one must also have the ability to spin a bigger gear. So other sessions are designed to improve pedal action & ...


9

No - Struggling away in the small rear cog/large front chainring combo is bad. Fitness is an overall term that has many components, so: If you want power you need to work on intervals, which is as fast as possible at full power for short burst times, then recovery time at a middling state. If you want to train for endurance, being at the steady state for ...


4

No, the ideal is to keep up a constant high cadence rather than to apply maximum pressure. Gears were invented for just that reason. Explanation: Muscles work better and develop better under lower strain. The evacuation of waste (lactic acid) is blocked when the muscle is under higher load.


3

If you don't feel like doing all these mental calisthenics on the bike, get a cheap speedo that runs off a magnet. Mount the readout on your handlebars and simply look at it to learn your speed. No need to overcomplicate this.



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