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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 ...


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 ...


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.


4

Use the Clutch! This is what I always tell people when I'm teaching them how to shift gears properly. Chain-rings and Cogs are machined with *pickup points" that assist transferring the chain from one ring to the other, they only work while you're turning the cranks. So I tell people to let all the power off of their pedals, but keep the cranks turning and ...


4

Completely stopping pedaling will not let you shift gears at all. You do have to reduce the tension in the top of the chain to shift front, so pedal, but with small force. The derailleur cannot push the chain sideways if it is under too much tension and thus pulled tight against the chainrings. It is normal to reduce pedaling force when shifting.


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

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 ...


3

I don't see any chain in the video. It (most) will do that with no chain. The spring is (hopefully) strong enough to pull an untethered derailleur into the cassette. Park Chain Length Sizing Now the derailleur may also be bent but that is something different. The rubbing in that video is only a problem if it rubs with the chain installed.


3

I know Im a little late for this posting but this is the first time I came across such question. I do own a Trek Lime, purchased back in 2007. This is a fully automatic bicycle. It has 3 speeds a front hub dynamo (speed sensor), a shifter module-solenoid (computer) under the center frame, and the 3 speed auto-shifter hub in the rear wheel. As far as I know ...


3

I'm familiar with RSX brifters (brake and shift combo units) If that's what you have then its likely the grease has gummed up, stopping the under-lever from engaging the release. You might be able to finangle it a couple times by manipulating the underlever carefully, and you'll feel it catch. A blast in the guts of the brifter with brake cleaner or ...


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 ...


2

If it was me, I'd release the gear cable so there is no tension at all on the front mech. Then move the gear lever / changer to the position the changer would be in if you weere in the 1st chainring. Then make sure that the adjusting screws are set correctly, so that when you look at front mech from above, it is centred over the 1st, smallest chainring. ...


2

As the Nuvinci system has been mentioned in other answers, I'll mention one more. SRAM makes the Automatix hub now. It's a 2 speed system (ratios 1:1, 1:1.37) with a centrifugal clutch. There's no manual shifting possible and no cables involved.


2

The chainwheel does not sit at the correct chain line is the answer. The most common cause is that you have an axle length shorter/longer than the ideal chain line. In this case, you have a shorter axle length. Did you add another chainring into your crankset? If the answer is yes, you will need to tweak around: either adding spacer (not recommended) or ...


2

I would concur that the solution here is to increase the length of the cable housing that is inferring with the rack. If the rack is putting any pressure on the cable housing, then it will interfere with the ability of the derailleur to shift properly. Depending on how much free cable is left over coming out of the derailleur, You will most likely need to ...


1

It sounds as though the return spring in the rear derailleur is no longer strong enough to push it back. Most likely the grease or oil in the system has dried out and become glue, probably dusty glue, over the time the bike wasn't used. One easy test (that may also fix the problem) is to leave the shifter set to high gear and while pedalling the bike on the ...


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 ...


1

There is a problem with the cable that links the shifter to the mechanism (rear derailleur) The cable has become slack over time and needs to be tighter. You can tighten it by turning a barrel adjuster if there is one present. it might be as pictured and there might be one where the cable leaves the shifter on the handlebar. looking in the direction of the ...


1

After watching both videos, I believe that whatever bent the rear derailer also bent the derailer hanger, which has your rear derailer out of alignment. The rear derailer/derailleur is that complicated part you replaced that moves the chain between gears on the rear, and also keeps the chain from getting loose and falling off. On most bikes, the rear ...


1

The derailleur was sticking. A bit of lubrication and all was good again.


1

The chain has to go pretty straight. The position you put it in - from big to big - is actually not the right position, so you should avoid this. But for the theory of your question: the derailleur leads your chain. While you pedaling the right way forward, rear derailleur leads the chain to rear cogs, and front derailleur to the chainrings. But when you ...


1

Right, so I took it to the bike shop and the issue turned out to be the gear cable being loose. The bicycle mechanic was a bit sceptical that this could have been caused by poor weather/fog so it's likely that in the process of cleaning my bike I loosened it up inadvertently (however I took it for a quick ride afterwards and it all seemed okay, so I'm not ...


1

Replacing the Racing T derailleur with the Athena 11s derailleur fixed the issue. The racing T derailleur seams to don't work with the 35mm Campagnolo clamp. Or generally don't work with frames wider than 28mm.


1

It sounds like the front derailleur needs adjustment. If you recently bought the bike from a shop then take it back for adjustment. If that's the problem then it will take only a few minutes. If it's worse, such a bent chain ring it will likely cost $$. If you want to do it yourself, check out the front derailleur questions. To change gears using ...


1

As Sander already noted not turning the gears will not allow shifting at all. Thus turning the pedals without really stressing them is key. When shifting to a higher gear with such a system it might be necessary to firmly press the shifting lever when shifting the front gear up, or even shift twice if misconfigurated. That stopping the pedaling helps for ...


1

Can't really tell much by your video. We see you clicking up & clicking down, but you don't appear to be turning the cranks. The gears will not shift unless the drive train is in motion.


1

If you're talking about a twist shifter, they DO make those still! Sram makes a shimano compatible version. Know that the MRX is shimano, and the other models that have numbers are sram only. If thats not to your liking, the thumb-shifter that Batman was mentioning is a solid option for a few bucks!


1

Typically not -- a few index shifters (like my Shimano 105SC 7 speed ones) have this option, but its primarily downtube and bar end ones for <=8 speeds. I don't think there exist any other shifters that do this other than possibly some grip shifts since they pretty much are letting pawls catch. However, you can buy friction shifters pretty cheaply these ...


1

A friction shifter allows you to continuously move the derailleur. The point of this on a front shifter (the left) is to trim the front derailleur. Trimming the front derailleur is when you tweak the position of the front derailleur to account for the change in chain angle with shifting, e.g. eliminate the chain rubbing on the cage of the derailleur. There ...


1

It sounds like an alignment issue, possibly with your limit screw for the lowest gear being "too low". Your best bet might be to follow a guide to realign the derailleur. Something like this



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