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Explain shifting to me

Old 10-25-10, 12:46 AM
  #1  
snarkypup
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Explain shifting to me

Okay, road bike experts. I know how to shift a three speed efficiently , but the 14 speed 89 Panasonic is a new world.

So... dt shifters. Left one is the big gears, right one is the little gears. That's about all I know. I think (and this is how stupid I am about this stuff) that if my chain is on the littlest big gear, and the biggest little gear, I'm in the lowest gear on my bike. Correct? Sheesh. I know NOTHING about this. Twenty-two years since I rode one of these, and I think I sucked at shifting then. I know one uses lower gears to climb, and bigger gears to go fast on flats and downhills, if one is so inclined. I know that when it gets too easy to pedal, I shift up. When it gets hard, I shift down. I bet there's more to it than that. What do I need to know to use my bike most efficiently, and to not look like an idiot?

Having seen Breaking Away many times, I realize that I need to avoid racing angry and imperious Italians. Otherwise, I feel like a total newb.

And I have both indexed and friction shifting. I do not understand this, either. I know I'm in indexed mode now. So folks, educate me!
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Old 10-25-10, 01:24 AM
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You're right on the lowest gear part. Low/high has to do with gear ratio (front gear/ring tooth count divided by rear cog tooth count).

Shifters pull a derailleur back and forth and basically force the chain off one ring and onto another. Index shifting assumes your cassette/freewheel cogs have a certain distance between them and the shifter is designed with this information to jump between the different cogs in the back. Friction shifting just moves the derailleur without any knowledge of the gears, so it's up to you to determine when you've shifted enough. Front shifters (left side) are usually always friction; I don't think front index shifting was really common for downtube/bar-end shifters (or until brifters came out).

As for shifting, I've found that for modern chainring setups, your shifting strategy seems to work well enough. Ideally, you'd want to shift such that your gear ratio goes smoothly up or down. I find this usually means I shift to the large front ring if I need a big jump in gear ratio, and then shift the small back rings if I need less of a jump. For city riding, I almost never need to worry about shifting between the front rings, but for longer rides, it helps a lot, esp on hills - getting momentum by shifting to high gear during downhill really helps. Other than that, the only other strategy I can think of is less shifting and more just pacing yourself - know your limits, don't push too hard at any one point or you'll wear out early. Sheldon Brown had some good advice too - as a rule of thumb, you should always be pedaling around the same cadence, so adjust your shifting so that you can maintain that cadence. It can differ with different chainring setups, like half-step gearing, but the principles should be the same.

Alright, that's my schtick. Someone who knows more than me educate us all some more
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Old 10-25-10, 01:52 AM
  #3  
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Everyone has their own preferences. The only thing that's really important is that it works for you. Pedaling too hard? - downshift. Pedaling too easy? - upshift. I like to think of the front gears as coarse adjustment and the back gears as fine tuning. I'll often just leave it on my fav gear in the back and ride it like a 2 speed only shifting in the front. Then fine tuning the back as needed to keep a comfortable load on the pedals. But, it's ALL about what's comfortable to you.

One thing you want to avoid when shifting is called cross chaining. That's when you have the chain on the smallest gear in the back and the smallest in the front at the same time, and vice versa. That makes the chain diagonal. It isn't very efficient and can cause premature wear to the chain and sprockets.
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Old 10-25-10, 02:35 AM
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Shifting and learning which way to pull on the shifters to get the gear you need just takes practice. Maybe take some time, when you're not in a hurry, and ride around simply shifting through gears until your body develops a memory of what to do. Then, it becomes natural and second nature. Ultimately, you'll get to where you can shift without having to look down at all.

Also, take a look at your bicycle. You'll notice the derailleurs are spring loaded. The spring has tension and so the derailleurs will naturally go to one side. On the front, it will go to the smallest chainring. On the rear, it will go to the smallest cog. So, when you pull on the shifters, you're always pulling to the larger ring or cog. Only what makes it a little confusing is that the largest chainrings are the harder gears while the larger cogs are the easier gears.

Suntour made a front derailleur that, instead, naturally went to the largest chainring up front. So, when you pull on the shifter, you went to the smaller ring and therefore the easiest gear. It was cool because all you had to remember was pull on either shifter and you're pedalling just got easier. That technology is not happening anymore, though....haha. Suntour Spirt was the derailleur model.

Anyway, if you have a bikestand, that's a really good way to tinker with gears and helps you remember how they work before you get on the bike and get yourself in a bit of a mess.........like running into a parked car trying to see which gear you're in. I've done that.........a looooong time ago. Ha!
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Old 10-25-10, 05:36 AM
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Unlike the situation with your 3-speed, this bike will permit you to accomplish the real goal of gearing, which is to maintain a nearly constant cadence of pedal rotation. Pick an "easy" gear to begin with, and count the number of times that your pedals spin (the same foot returning to the original position) in a 60 second period. When you have it in the 80-90 range, you're at the starting point.

Now work to maintain that cadence during your entire ride. You don't have to be going fast. Just let your body adjust to the feeling of this motion. Soon it will become the "natural" condition for riding, and you can progress from there.

Adjust the gears so that the same cadence results whether you're going up a hill, into a headwind, or rolling easily on level ground. As your body (muscles, heart, lungs) strengthen(s), you will be using a "harder" gear to accomplish the same cadence under the what previously had been more stressing conditions. Speed will improve accordingly. You're body won't know the difference, basically. Only your wristwatch will know that you've gotten faster.

Try it!

PG
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Old 10-25-10, 06:07 AM
  #6  
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Go to SheldonBrown.com and click your way to the gear calculator. Go to your bike with a piece of paper and pen/pencil. Count the number of teeth on your two chainrings, probably something like 53 and 39 or maybe 52 and 42. Then count the numbers of teeth on your rear cogs, probably something like 13-14-15-17-20-23-27. Plug those numbers into the gear calculator and hit calculate. You can set the calculator with your wheel size and how you want the output. I just use gear inches. Print out the resulting chart and tape it to your handlebars.

Basically (ignore half-step gearing for now) use your big chainring with the smallest four or five cogs, and use the small chainring with the biggest five cogs. The middle cogs get used with either chainring. You will shift the back for little changes, and the front for big changes.

Time and practice.
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Old 10-25-10, 08:02 AM
  #7  
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snarkypup, With saddle time smoothness and knowing how much to shift will all come together, but it seems you have the basics of how to use the gears already. I'm guessing that the LH shifter for the front derailleur is friction and the shifter for the rear derailleur is indexed. This is how I have my two DT shifting bikes set up. The non indexed front shifter allows for 'trimming' the FD to prevent any chain rubbing on the FD cage (what the chain passes through).

Brad
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Old 10-25-10, 08:23 AM
  #8  
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Just Ride it everyday for a week. You'll know which way to move the levers without thinking after that. Although I must admit that occasionally I have a brain fart and shift in the wrong direction...I doubt I'm the only one either

I think the most important thing to learn early on is to trim your derailleurs. There's a little play within each rear gear where you're in the gear but your RD isn't perfectly lined up over the cog. A little too much in either direction and you'll start to hear that chk-chk-chk-chk sound of the chain moving towards the next cog. Once you're in a gear adjust the lever very slightly until the drivetrain is silent. That is a properly trimmed derailleur.

Same goes for the front Chainrings and Derailleur. As you shift through the rear cogs the chainline changes and the chain will rub on the insides of the Front Derailleur cage. You'll need to adjust the front derailleur ever so slightly as you move through the rear cogs to keep it trimmed up. You don't need to trim the FD on each rear shift, just when you hear the chain rubbing on the derailleur cage.


***EDIT***
Whoops!! You are indexed disregard my comments about the rear shifting.
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Old 10-25-10, 10:32 AM
  #9  
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Originally Posted by snarkypup View Post
I know that when it gets too easy to pedal, I shift up. When it gets hard, I shift down. I bet there's more to it than that.
No, actually you pretty much nailed it.
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Old 10-25-10, 10:45 AM
  #10  
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Easy.

New boyfriend.
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Old 10-25-10, 12:12 PM
  #11  
snarkypup
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Originally Posted by RobbieTunes View Post
Easy.

New boyfriend.
Aw, are you offering? All I really want is your saddle.
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Old 10-25-10, 12:20 PM
  #12  
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Originally Posted by Zaphod Beeblebrox View Post
Just Ride it everyday for a week. You'll know which way to move the levers without thinking after that. Although I must admit that occasionally I have a brain fart and shift in the wrong direction...I doubt I'm the only one either
No, I think it's just you, man.

Treebound offered some solid advice; read what Sheldon has written. Otherwise you're just asking for advice from people who admittedly make shifting mistakes.

Seriously, just as ZB said, you have the correct understanding and in no time it'll become second nature.

Also, try not to pi$$ off other riders who carry frame pumps. Not cool, Italians! Not cool!
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Old 10-25-10, 12:41 PM
  #13  
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Originally Posted by snarkypup View Post
Aw, are you offering? All I really want is your saddle.
That's what they all say.
I'll clean it and send pics.....

(this gets worse and worse...)

Last edited by RobbieTunes; 10-25-10 at 12:45 PM.
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Old 10-25-10, 01:40 PM
  #14  
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Originally Posted by snarkypup View Post
I know that when it gets too easy to pedal, I shift up. When it gets hard, I shift down. I bet there's more to it than that.
Yes, but not much more, just 2 more things:
1) Plan ahead. You know a hill is coming, so shift down before it gets really hard (or up before it gets really easy).
2) Practice. Experience makes (1) easier.

Once you get good at that part, there are refinements to technique, but that'll get you a long ways down the road.
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Old 10-25-10, 01:57 PM
  #15  
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Use the big gear in front; use a middle gear in back; stand when the hill gets steep; walk if the hill gets too steep.

When you get there, hang your hat on either of the two little hooks provided.
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Old 10-25-10, 02:15 PM
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Another easy way to remember gearing is based on the relative sizes of the rings/cogs you're on--think of the difference between the size of the two rings; the bigger the difference between front and back, the bigger the gear; the smaller the difference, the smaller the gear (if you were turning a chainring and cog that were the same size, you'd be in a neutral gear).

I've been recently practicing more on my downtube shifters, and one thing that helps but which is a bit awkward at first is to remember to keep leaning forward as you're shifting. I used to try to keep my head and shoulders up and then feel for the shifters, but I've found it easier to drop everything as though I'm going into a tuck on the drops, and then shift in that position. I have some old Suntour shifters on my current ride, and I do like the fact pulling on either lever simply means "lower gear/easier pedaling."

One thing I read from Jobst Brandt which also helped said, "when shifting, the rider should lighten his force on the pedals, only lightly moving the chain forward." This helps the derailers move without too much undue strain on them.

I also keep my starting reference w/ the little chain up front and the larger cogs in back--the lowest gears. I then upshift with the rear derailer till it either feels right, or it feels like I could use more power (e.g., on a dowhill.). Then I will shift the front derailer and see where to go from there with the rear.

Finally, avoid shifting under heavy load; it not only can be hard on the derailer, but the sudden jolt can affect your balance, etc. That means shifting before you start heading up a hill and as I said above, pedaling lightly as you shift.
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Old 10-25-10, 02:24 PM
  #17  
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Loving all the advice, guys! I think I understand enough of this, then, to do what I'm doing right now. I think it's just me, but I find Sheldon really hard to follow. I'm a teacher, and we talk all the time about something called "background knowledge," and the assumption that your reader already knows certain things and can therefore follow your references. I feel like Sheldon's making some assumptions about stuff that I don't already know. I read through his page on shifting and felt just as stupid at the end as I did before I read it. Oddly, you guys don't make me feel that way. I know everyone else loves Sheldon, so it's really probably just me .

The 3-speed was actually helpful for learning all this. It's so simple, but with a SA hub, the lower gear is really high, so boy... you shift, or you die. And the highest gear is so freakishly beautiful for straight patches that I use it a lot too. I shift more on the 3-speed than any other bike I've ever owned. But I think it's helped me to understand when to shift up and down, because I'm not trying to work with 21 gears or 14 or even 10. Just 3! I've been working with my boyfriend's daughter, who is nine and riding her first bike with gears, on shifting down. Her dad has told her that if she stays in the higher gear, she'll get a better work out. Needless to say, he doesn't really ride much. So the other day, we're riding up this really tough short hill, and I see she's stopped and is walking her bike up the hill. Yet I'm on the 3-speed Sports, and I'm riding up it. What's up? Well, she's still in like... 20th gear. So we had to have a chat about shifting down. It's odd how explaining something to someone else helps you understand it yourself.

But reading all these posts helps too because a: I feel less stupid (there's not some magic thing I'm not getting) and b: I know about cadence now, and it makes perfect sense to me. If I can expend roughly the same amount of energy over a longer ride, I can increase my endurance. The part about trimming the deraileurs was amazing too, as I had sort of figured that out through trial and error, but thought it was just me being a newb and ruining my bike. Now I know it's a skill. So cool! Thanks!

I still don't get the indexed vs. friction thing. How can a gear be incrementally on or off? Isn't it either on the cog, or not on the cog? So when would one want to switch to a friction set up? Mine is currently on indexed. But I can switch, at least the smaller cogs. Why would I do that? When would it be useful?

And let's say that I'm riding along in the lowest gear (little big cog, big little cog), but I want to quickly go to a middle gear (big big cog, big little cog) to pick up speed before a hill, then shift back down rapidly to go up the hill. I assume I don't have to shift through all the intermediate gears, yet when I tried just switching the left hand lever, it made a lot of noise and scared me, so I stopped. What's the scoop on a situation like that?
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Old 10-25-10, 02:41 PM
  #18  
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It's the same as a manual transmission in a car, and the rate you're peddling is like the RPM of the car's engine. Once you spin too fast you need to shift to a higher gear ratio in order to ride efficiently, whereas if you're going up a hill, your legs won't be able to spin fast enough if the gear is too high (not enough torque, like starting off on a hill in downtown seattle in 4th gear) so you need to downshift.

If you've never driven a manual this won't help at all. LOL!
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Old 10-25-10, 02:48 PM
  #19  
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Originally Posted by snarkypup View Post
I still don't get the indexed vs. friction thing. How can a gear be incrementally on or off? Isn't it either on the cog, or not on the cog? So when would one want to switch to a friction set up? Mine is currently on indexed. But I can switch, at least the smaller cogs. Why would I do that? When would it be useful?
Indexed shifters have detents, or clicks, built in. They move the derailleur a set amount from one gear to the next. Friction shifting does not have those clicks, but is infinitely variable, so you can move the derailleur anywhere (within its movement range). This means you can hit gears, or kind of hit them, or maybe miss. As mentioned before, you need to listen to the sound to tell whether you are right in the middle of a gear or not, and make adjustments accordingly.

In your situation, I'm not sure you would ever want to switch to friction.
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Old 10-25-10, 03:05 PM
  #20  
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Originally Posted by snarkypup View Post
<snip>
And let's say that I'm riding along in the lowest gear (little big cog, big little cog), but I want to quickly go to a middle gear (big big cog, big little cog) to pick up speed before a hill, then shift back down rapidly to go up the hill. I assume I don't have to shift through all the intermediate gears, yet when I tried just switching the left hand lever, it made a lot of noise and scared me, so I stopped. What's the scoop on a situation like that?
Changing the front can require you to let off the pedal force for a bit before the gear actually shifts- that's because the top of the chain is under pedal tension and the bottom of the chain is tensioned by the rear derailleur springs, and the gears change from the chain flexing sideways. The pedal force keeps the chain from bending, so the derailleur can't move it off the chainring, so it just rattles. Letting up on the pedaling just a little can allow the chain to bend enough to move from one chainring to the other. Mostly, if I know a hill is coming up, I'll just stay in the small chainring, since if you wait too long to change chainrings it becomes impossible when the hill starts. But I'm kinda a weenie, and not much of a racer.
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Old 10-25-10, 03:10 PM
  #21  
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Originally Posted by Pars View Post
Indexed shifters have detents, or clicks, built in. They move the derailleur a set amount from one gear to the next. Friction shifting does not have those clicks, but is infinitely variable, so you can move the derailleur anywhere (within its movement range). This means you can hit gears, or kind of hit them, or maybe miss. As mentioned before, you need to listen to the sound to tell whether you are right in the middle of a gear or not, and make adjustments accordingly.

In your situation, I'm not sure you would ever want to switch to friction.
Au contraire, I was thinking that switching to friction (eventually, but not right away) would offer a good exercise in practical function. Sometimes it's tough to get why something is better or worse without having experienced the alternative and in this case I think the alignment issue would be instantaneously obvious.

But yes, as Pars said a derailleur can be left or right a bit of the cog that the chain is on and that's not really good. It wears things prematurely and if it's off by a sufficient amount and you decide to put some power down the frame can flex enough to shift unexpectedly. Trimming derailleurs becomes second-nature after a while, though, and out of 22 bikes I only have one with indexed shifting - mainly because I don't have to keep adjusting friction bikes over the years like I do with the indexed bike.
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Old 10-25-10, 03:18 PM
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Originally Posted by snarkypup View Post

I still don't get the indexed vs. friction thing. How can a gear be incrementally on or off? Isn't it either on the cog, or not on the cog? So when would one want to switch to a friction set up? Mine is currently on indexed. But I can switch, at least the smaller cogs. Why would I do that? When would it be useful?
Snarkypup, it helps to understand this if you can somehow lift the rear wheel up while looking at the derailer, like on a bike stand, or just having someone like your boyfriend lift up the seat and let you pedal. Then shift the derailer on back to see how the derailer moves. On an indexed bike, what happens is the derailer "jumps" from one discrete, set position to another. That position is determined by the derailer's angles and the cable length--NOT the position of the chain. And again, the key is that the derailer's position location over each cog is a discrete spot (these are the "detents" mentioned above). In fact, the position of the chain is determined by the position of the derailer. This should make more sense if you look at a derailer closeup and from behind as you shift the gears. You could also compare that to shifting a friction derailer (there should be a dial on the index lever that, when loosened, will allow you to switch from friction to indexed and back), and note that with a friction shift, the derailer doesn't have set positions--it simply moves inboard and outboard relative to the wheel. Where it stops is determined by where you leave the lever and the cable is pulled to, not by a setting in the derailer. In both cases, the chain rests wherever the derailer lines up. This is why you have to "trim" the derailer in friction mode, because the initial shift can leave the derailer over a spot between the cogs, or slightly off-center of the cog, and then you will hear the chain scraping against the derailer and the inside or outside of the teeth of the cog. Hopefully, that will help you visualize this better.

As far as which is more useful, it's up to your preference. Nowadays, everyone is used to using indexed shifting in the same way most people are used to automatic transmissions in cars. In a sense, you don't have to think about what you're doing so much. However, indexed shifting requires a bit more maintenance, because if the derailer goes a bit out of whack, or the cables get stretched, the system can become misaligned, and then every gear makes noise or grinds. In such a case, when you change back to friction, you can use the shifters and derailers fine. I would say if you really want to learn to shift and how the bike works as you ride it, you should learn to ride comfortably and shift easily with your derailers in friction mode. Once you're very comfortable doing this, then going to indexed shifting will provide you with a possibly more convenient riding experience--or you'll feel like you don't have any more interest in giving up that control over the bike. But it's up to you.

Originally Posted by snarkypup View Post
And let's say that I'm riding along in the lowest gear (little big cog, big little cog), but I want to quickly go to a middle gear (big big cog, big little cog) to pick up speed before a hill, then shift back down rapidly to go up the hill. I assume I don't have to shift through all the intermediate gears, yet when I tried just switching the left hand lever, it made a lot of noise and scared me, so I stopped. What's the scoop on a situation like that?
Because of the difficulty of cross-chaining, you never want to have that big-big combination: don't put the chain on the big ring in front with the big ring in back.

Best in such a situation as you describe is (a) as you're going downhill, make sure you've upshifted the REAR a few cogs first, and THEN shift the front from the little to the big. This way, you're on a middle gear. If you still want to go faster at that point, then you shift the rear to even smaller cogs (outside). But as you are about to go uphill, again, you want to get to the middle rear gears first, and then shift the front. In both cases, you're trying to avoid the "cross chaining" others mentioned before.

One thing to remember in general is, if you're heading downhill (or are on flat land), then shifting to the bigger cog in front should be fairly easy; the thing is, the more teeth you're moving the chain ONTO, the slower the shift will be, and the more it might "make noise." There will be a bit of a delay before this engages, also, because of the extra teeth. And as noted before, you want your legs to be applying lighter force to the pedals as you shift; this will make either derailer perform better and with fewer issues.

Last edited by peripatetic; 10-25-10 at 03:21 PM.
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Old 10-25-10, 03:28 PM
  #23  
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Originally Posted by snarkypup View Post
I still don't get the indexed vs. friction thing. How can a gear be incrementally on or off? Isn't it either on the cog, or not on the cog? So when would one want to switch to a friction set up? Mine is currently on indexed. But I can switch, at least the smaller cogs. Why would I do that? When would it be useful?
The Index/Friction selector on your gear lever is a personal preference thing. Some folks don't want indexing so they switch it off and use it in friction mode. The switch also doubles as a fail-safe if the adjustment on your Indexing gets out of whack when you're far from home. If that happens you just switch to friction and shift it that way until you get home and can perform whatever adjustments are necessary.

I think of my cogs like walking a tightrope. You can be leaning a little off-center to either side without falling off (changing gears) but you're most comfortable (most efficient) when you're right over top of it. Indexing makes it so your Derailleur jumps directly to the middle of the cog (tightrope) each time. Friction you're sort of rolling through the cogs and you end up using your sense of Sound and Touch to determine when the derailleur is optimally adjusted.

There's a dude named Frank Berto who did a lot of writing on the subject and put it in a book called "The Dancing Chain". When you see an old pro really working a friction shifter its easy to see where he came up with that Title.


And let's say that I'm riding along in the lowest gear (little big cog, big little cog), but I want to quickly go to a middle gear (big big cog, big little cog) to pick up speed before a hill, then shift back down rapidly to go up the hill. I assume I don't have to shift through all the intermediate gears, yet when I tried just switching the left hand lever, it made a lot of noise and scared me, so I stopped. What's the scoop on a situation like that?
Just shift right past what you don't want. Nothing wrong with that and its kind of a nice advantage that levers have. You can go from the biggest cog right down to the smallest and back again. Its gonna makes some noises that it wouldn't if you're just shifting one gear at a time but its not gonna hurt anything. Just be sure you're pedaling while you're shifting and you are golden.

Bicycle drivetrains are built pretty tough.
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Old 10-25-10, 04:30 PM
  #24  
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Making big "moves" when shifting can sometimes be a little risky. Anticipation is a good way to avoid that. Fortunately, you can see hills coming, and stuff like that.

Indexed and friction shifters make it easy to skip cogs and stuff like that, but I'd practice a bit before I started jumping around front and rear. After you learn to make smaller shifts smoothly, it's easier to make bigger shifts smoothly.

Early on, "be easy on yourself." That is, keep in a gear you can comfortably handle, because the inevitable missed shift or late shift will come, repeatedly, and you're less likely to be stopped dead in your tracks by any of a few malfunctions that late, desperate shifting can cause. For example, a nice long downhill can have you on the big ring up front, small cog in the rear, but the uphill that follows may beg the complete opposite. What speed you sacrifice by not going whole hog downhill can be gained by keeping momentum going uphill.

The key is to let the gearing do the work, keeping your cadence somewhat steady, which is much easier to say than practice. Until you master this, don't be afraid to spin a little faster on short sections where there is an inevitable uphill grade to follow. Also, don't be afraid to stand and pedal harder if the uphill is short.

Once shifting is second nature, you won't have to worry about that nearly as much.

It'a almost always about momentum. Keep that in mind, and you'll figure out that you don't have to shift to extremes nearly as often.

As far as "The Dancing Chain," it truly is fun to follow an accomplished cyclist on varying terrain and watch the chain moving around while his/her cadence rarely changes. I don't see it nearly as often in group rides (norskagent is an exception, a nimble and practiced shifter), but lately in triathlons, I've been able to watch folks on their tri-bikes working the gears quite often to maintain the higher rpm's that the riding position seems to warrant.
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Old 10-25-10, 04:41 PM
  #25  
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At any rate shifting a bicycle isn't something you'll get good at by reading about it online
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