Mr. DNA

Can anyone tell me what the advantage is to having a 9, or even an 8 speed bike is? Likewise with a triple chainring in the front? I'm assuming I'm missing out on something really basic about gearing, but I don't quite understand the need for so many cogs, or especially for 3 chain rings.
Thanks for the feedback

bg4533

For a beginner on a flat road I would have to say almost none. For an experienced rider varying between mountains and flats or a mountain biker who rides trails and streets a lot. A rider in the mountains or in really rough terain may need a very low gear to pedal evenly and not get worn out quickly. Then comes a flat surface and the rider needs a lot bigger gear. A sprint and even more is needed. People also tend to ride much lower gears on very long rides. Basically, it is frequently varied terrain and situations that require so many gears. However, there are plenty of single speed/fixed riders that demonstrate only 1 gear is needed.

Also, on a triple there are some gears that arent really usable. The largest chainring with the smallest few cogs is not optimal. Same with the oposite.

mrfix

My new bike is 1 X 9, a single 53 up front and an 11 X 34 in the rear. It gives me the gearing I need and the spacing between gears gives me exactly what I'm looking for when i shift up or down. The lack of the front derailure, small ring, cables and shifter as allowed me to build a 13.5 pound road bike.

RainmanP

It depends on your terrain and how you ride a bike. It is quite flat here in New Orleans so for my 22 mile round trip commute I often ride a singlespeed or even my fixed gear. When I ride a multi-speed bike I seldom shift gears. Obviously if one lives and rides in hilly or mountainous terrain one needs the option of low gears. For routine riding these needs can often be met with relatively few gears.

However, when one has focused on developing a smooth, round pedal stroke and cadence in the 90-100 RPM range it becomes necessary to have numerous gears to select from to be able to maintain the same cadence and relative pedalling effort with slight changes in speed when riding in a group. Maintaining this consistency is important to riding efficiency, and becomes particularly important on long, brisk group rides or races. If you don't have close gear ratios and are forced to use a harder or easier gear than you need, your pedalling effiency will suffer. Too hard a gear, your legs will get tired from having to "push" too hard. Too easy and your legs might be fine, but you will begin to get out of breath because you are having to spin faster than you are used to. This is why you see lots of gears on bikes, for those who race or like to participate in long, brisk group rides. Most of these people not only want many gears, but want them close in gear ratio, ie, 1-tooth increments in back, like 12-13-14-15-16-17-18-19-21, or 13-23, etc.

Offroad mountain bikers have different needs. They may encounter flats or short, very steep spots. So they prefer 3 small chainrings up front and wider gear ratios in the back, like 11-12-14-16-18-21-24-28-32, or 12-34. Again, this allows them to find the right gear to maintain their preferred cadence and effort.

Noodling around town one is all you need.
FWIW,
Raymond

MichaelW

The no of cogs in the back makes little difference to the average rider. Beyond 7 cogs, its mostly about marketing. They do allow single tooth steps for time trials.
Triples were developed in the 1930s for touring cyclists, and are pretty much essential. A touring cyclists can find himself gunning along with a tailwind and a downhill, or having to haul a camping load up a steep, unsurfaced trail. The easiest way to achieve that range of gears is with a triple.
Im surprised that more people dont use 1x9 speeds, since you can get a considerable range for everyday road riding very simply. It is a popular system for cycle couriers.
Other less common systems are low-ratio doubles, as found in cyclo cross. These are good for non athletic road riders.
For just riding around town, carrying some shopping, it depends how hilly your town is. I've lived in places where a 1:1 ratio was essential.

AndrewP

Car engines work efficiently from 1500 - 4500 rpm a ration of 3:1, so 5 gears will cover speed ranges of 4-12 mph, 10-30, 15-45, 25-75, 35-105 with a fair amount of overlap. Legs only work efficiently from 80-95 rpm, a ratio of 1.2:1. With this limited range of speeds that can be covered efficiently in one gear ratio, you will need 12 gears to cover a range of speeds from 4-35 mph. Many of the gears on a triple are effective duplicates, so there may only be 12 distinct gear ratios available.

lsits

I have a triple with a nine-gear cassette. I do most of my riding on the middle chainring. While there I use mostly numbers three through six (sometimes seven) on the rear. When I climb a hill I go down to my smallest chainring and use numbers one through five on the rear. I don't really use my largest chainring much. Just a couple of times where there was a long shallow downgrade. If it's a steep hill, I usually just coast. The two smallest cogs on the rear don't get used much. I could probably get by with a seven-cog cassette, but that would mean going with Sora components. I think that the 105 rear derailleur (sp?) is of a higher quality.

lsits

Um... Don't you mean the largest chairing coupled with the largest cogs and vice versa?

khuon

On the subject of overlap, this is oftentimes intentional. Some combinations are not really good for the drivetrain due to large chain deflection so you need to cover those ratios using a different combination. Other combinations are not easily reached in a timely or smooth manner. For instance, it is often easier to shift the rear derailleur than it is the front. So some riders position their gears so that they can achieve some of the same (or very close to the same) ratios by moving the rear as opposed to their front. This often saves time and in certain cases can decrease the chances of dropping the chain.

shecky

Obviously, most bike riders don't need the 24+ gears that bikes often come with these days. There are some factors to consider.

While a basic 3 speed hub would probably suit the needs of most bike riders (as opposed to bike enthusiasts), try finding a 3 speed bike that's competitively priced with a 21+ speed with lots of redundant and sometimes unused gearing. Of course, marketing is a whole other can of worms, witness the dual suspension knobby tired MTBs that never leave city roads. (Reminds me of the trend in autos.)

Some gears are basically useless. I saw some MTBs with 24 front/34 rear granny gears. Ridiculously low, almost too low to even balance, uncompetitive with walking. Some clusters are so wide, three chainrings are needed to keep the chain from veering too far sideways. The mentioned large chainring/large cog, small chainring/small cog combos are less than ideal.

Personally, I think 5 well spaced gears would suit all my needs just fine. Then again, this is from someone who often rides one speed bikes.

froze

I would agree that if you have a touring bike that you load up on or a mtb bike then you need the triple so you have the use of a granny gear to get you going. But if you have a normal road bike than the triple is overkill unless your physically not strong enough (due to weaker muscles or bad knees). I use to live in California a did most of my riding starting at the town I lived in and going up into the mountains above Los Angeles including Glendale and Pasadena, San Bernardino, Santa Barbara, Ventura, and Bakersfield and did all on a 12 speed for 25+ years and only the last 4 years with 14 speeds (I replaced the 6 speed rear cluster with a 7), and I never had a need for a smaller front gear when I was younger and still didn't up until I moved to the flat lands of Indiana just 3 weeks ago with old legs!

Miyataphile

I still ride an 6 spd (1 front x 6 back) The largest cog is 34T and the smallest is 13T. I live in an area that is varied (lots of hills and flats) but I don't need to "upgrade". I fact, I don't even have a front derailleur. I just use the smallest chainring 28T. So for me 6 speeds the all I really need. I could also go 5 speeds, but finding a 5 speed cog with a low granny 34 T is hard to find.

Miyataphile

stinkyonions

my everyday bike is a 48:16 fixie and the thing rocks. i think you begin to see how many hassles gears cause when you start riding ss or fixed. for me, gears are still essential for longer rides in berkeley since getting up some of the excessive grades would be near impossible on a fixed. less gears also gives you a better feeling of 'triumph' and 'conquering' when you make it to the top of that steep hill. while i think gears are a necessity for longer rides, i find them useless for just getting around town or campus. i'd rather put more focus into avoiding cars and people and not worrying about what gear is easiest for the approaching hill.

Rural Roadie

Need? In my area I could get by with 5 or 6, a 14-28 would cover it.
In fact Im setting up right now a Schwinn Traveler 1x7 just to see if I like it that way.

prestonjb

I think that is the real answer. Manufacturers must cover a broad range of abilities and climates.

Personally I build my own casette ratios and utilize them for specific needs. Actually this breaks down into that I tend to use stock casettes for all but the steepest of climbs.

So in flat land florida where the average grade is 0% I tend to stay with a fairly tight cluster of 12-23. The 12 is because I rarely can get the speed up to take on the 53x12 for very long. I do find the 23 to be a little low for the 39x23 but I use that gear in SoutFlorida all the way up to mid-Florida.

In the Apalacian mountains I use a 13x30 in North Carolina on the mostly uphill Assault on Mt Mitchell.

In North Georga for six-gap, I change to a 13x32 to protect my knees on HOG-PIN-GAP with the 4 mile section at 12% grade!

I hope during the development of the 10-speed Shimano that I will be able to build simmilar clusters for the 10-speeds... Esp for 6-gap because I find, being a flat-lander, that I am faster between-passes than the locals and I need to get the extra gears to help keep my cadence smooth.

On my tandem those SUPER LOW gears that seen unusable on mountain bikes are actually perfect for the tandem... Climbing Col de Tourmalet was 12 miles of 8% grade and having the 33x34 as the bail-out gear was essential. Of course the secret to climbing Tourmalet as we discovered was to switch up 3 gears and hop out of the saddle (both of us) as we rounded the right hand switch-back turn. The Bask's also tought that was way cool as they stood up and cheered us on to the top!

Check out our pics of the climb... Notice the middle pick and you can see the MASSIVE 34T rear sprocket!

https://geocities.com/cyclebikers/July_21_Mon/

Retro Grouch 

Truth is, I don't really "need" a bike at all. I could survive without one but my quality of life would suffer. The short answer to your question is: I "need" to have however many gears it takes for me to feel like I'm having fun. There are clearly advantages to having lots.

When I'm riding on a flat road, I like a gearing system that has lots of choices grouped real close together. That way I can always find a gear in the "sweet spot" where it doesn't feel like I'm either pedaling too fast or having to push too hard.

When I'm riding in a hillier area, I like to have some real easy gears for the climb because I'm something of a wimp, and I like to have some real fast gears for the downhill just because. On the hills I also like the gears to be spread out more so that I can feel more of a difference when I shift.

I don't own a fixed gear bike yet, but I keep thinking that I'll build one up for myself. If and when that happens, I may only "need" one gear to have fun.

mrfix

Retro Grouch has got the idea, commuters need to get where they go, some with heavy loads. Some cycle for fun on level roads and others in the hills. Riding a bike is for fun and health, if you race, use the gearing that best fits the course the race is run on. As far as fixed gear bikes go, they are fun, load it up and head for work in new england and you may not make it. On the other hand, riding a tripple in south Florida is'nt always worth it either. Sometimes budget has a lot to do with what we ride. Ride a bike, build a relationship with it and have fun.

BlissfulAbyss71

WOW! 22 miles?! Im in New Orleans too, Thanks so much for explaining this. I just recently took a job in the CBD and none of the parking garages have clearance for my exceptionally tall van so Im trying to research alt travel methods lol. This helped a lot- I was wondering if multiple gears here in flatland was necessary.

alcjphil

When this zombie thread started, 9 speed cassettes were almost new. Put this one back into its grave

bobwysiwyg

Oh,oh, zombie thread police on the prowl again.

rydabent

My trike has 24 speeds, and my bike has 27. When riding them I really dont notice any difference. Again with a triple in front granny is for going up hills, center ring is for most riding, big ring is for down hills or with the wind. I then just shift across the rear cluster as needed.

joesch

Atleast one (1)
Add more depending on your terrain and abilities.

San Rensho 

For my around town bike, 3 speeds is all you needs. For my road bike, 18 of the closest spaced gears possible is what I use in flat Miami Fla. So I guess it depends.

AnkleWork

And it's OT. At least someone pays attention.

Mods please close this old idiotic thread.

HillRider

That's really not true. Assuming 26" wheels, a 24x34 gear combination at a 75 rpm cadence is about 4 mph. You cannot walk up a steep hill at that speed, particularly if you are pushing a bike.