w98seeng

Bacciagalupe posted about 'Future-Proofing a 9 Speed Drivetrain' and operator said "Future proofing a 9s system is like future proofing an 8 track."

Why is this? Why do we need so many gears? For a mountain bike I can see having a wide range of gears because the terrain can change so drastically. But for a road bike it's basically flat, up and down, so is it really necessary? I understand progress, but can't progress come in other forms, like materials, weight, durability, pricing?

Please do not say "yes" without giving an explanation. I have been wondering about this for a while.

Also, is it really necessary to have close ratios in a cassette, like 12/13/14/15? What type of riding or rider uses these ratios? How does it compare to a cassette with 12/14/16/18 ratios? I have a SRAM PG970 9 speed cassette (11, 13, 15, 17, 20, 23, 26, 30, 34). I used this on a hybrid I built a couple of years ago, but I recently put the wheels on my cyclocross bike and I am wondering if I should change the cassette to something with different ratios. If so, what is a good combination for road use by a novice rider?


Many Thanks for the info,
Ian

rhenning

We don't need more gears as it is just a marketing ploy to get your money and make it so you can't find replacements for your old stuff. The more gears you have the more duplication of gears you have and the less usable gears are available. Roger

w98seeng

Just out of curiosity, professional or high amateur racers, how many gears do they use? Not how many are on their bikes, but how many do they actually use?

On the question of my changing my cassette, I'm thinking of getting an 11-28 cassette for my cyclocross bike. Is this a good ratio? What cogs should I get?

Ian

StanSeven

The answer is as you gain experience, you'll find the optimal cadence for you. More gears allow you to maintain that cadence when the terrain changes. In other words, you keep the most efficient effort within a narrow range.

Doohickie

I do just fine with 6-7 gears in the back. Anything beyond that is gravy.

davidad

It's mostly marketing hype. The high end market is limited so the manufacturers come up with new and improved stuff to create more sales. I have a tourer set up with 7sp half-step. I have 18 different gears with no overlap from 16 inches to 107 inches with a 10% spacing. The rear cogs are spaced at 20% and the front at 10% and it does sometimes require a double shift.

Charles Ramsey

When you are riding fast the biggest force against you is the wind. Horsepower is the cube of speed so shifting from a 13 to an 11 tooth cog is (13/11)^3=1.65 this is a big increase in horsepower and is hard on the body. On the other hand when riding slow the biggest force is climbing a hill. In this case shifting from a 30 to a 34 is just 30/34=.88 this shift is hardly worth doing. The reason why cogs are built this way is it is easier to shift over smaller steps. I'm using a 12 14 16 18 21 24 30 39 https://share.ovi.com/media/currentre...resident.10233 the shift from 24 to 30 is just about right and the 30 to 39 shift is real close and I plan to build a 40 tooth cog for the rear.

dabac

Need is a tricky word in these circumstances. Not many of us actually "need" to ride a bike in the first place, we, more or less, do it out of choice rather than out of necessity. So if we don't "need" the bike, we certainly don't "need" the gears.
If you're a parts manufacturer you need to keep the sales volume up, for which an engineering change is a useful base for a sales pitch.
If you're a pro racer you need to remain competitive, and in a setting where fractions of a seconds can determine a podium finish, you can't afford ignoring a potential advantage, no matter how small.
If you're a sponsored rider you'll pretty much ride what you're told, although every now and then (a famous)sponsored rider will have his/hers favourite piece of kit rebadged and disguised, if it happens to be from another manufacturer.

More sprockets in the rear does give more ratios available at a single shift, which is a tad easier to handle than setups that require double shifting.

There's that word again...

But I like it. My knees needs pampering, and close ratios does help me keep the speed up w/o blowing my knees. If I haven't got close ratios I'll just suck it up and either accept a very modest reduction in speed or do a bit more honking. Outside a race setting, it's not an issue.

I don't know if I'm cocky enough to give such wide recommendations, but I've developed a fondness for close ratio cassettes that start with 14. I don't need the top speed of an 11T, and a 14T(and the rest of the cassette) will last noticeably longer.

Booger1

Next time I'm dressed in my team kit and helmet,legs shaved for aerodynamics or in case I fall and get a scab,chainring tatoo proudly displayed,racing around town in a pace line with 20 of my buddies on my carbon bike,with my sparkly shoes and pedals gleeming in the sun,aerodynamic shades sucked tight to my face,blowing red lights and blocking the street,eating bananas and Cliff bars and sucking back gels,washing it all down with some mix that somebody told me is good for me,while dabbing on some more Assos and adjusting my Take-a Look,I'll think about it......Meanwhile,I'm fine with 7.

fietsbob

It's the Ratios that the combinations of 2 different chain cogs provide.

And it's the Boat payments the Engineers Owe.

FBinNY 

The best analogy for why we keep seeing more gears (whether they're of benefit or not) is an arms race. Much of the history of the world is based on which society could deploy weapons superior to the current state of the art. Iron, trumped Bronze, and so on.

Likewise for makers of bikes. Being to boast of more gears, especially being the first to offer them, is a powerful selling tool. More features, mean more talking points, means more sales. On the flip side, not having a feature that the competitors offer is a major handicap. Selling the benefits of fewer gears is a serious uphill effort.

Since new bike sales account for well over 90% of component production, and since the bulk of those sales are 1st or 2nd bikes, marketing effort will always be directed to that end of the market.

For most component makers the high end serious cyclist isn't a major source of revenue. High end product for this segment isn't about making money as much as it's about being flagship product to establish the credibility for the mainstream lines, where the real dough is.

MichaelW

I recently "upgraded" my bike from Campagnolo 8 speed to Shimano 9 speed. The Campy was simply un-maintainable with no spares or replacements available.
I'm a bit dissapointed in the 9 speed. I think the rear sprockets are too thin, esp in big touring sizes. They may work well when carved from aluminium billet but the cheaper stamped steel ones are too flexy.
Chains are thinner and for the same price and grade, the rate of wear is higher.
Cable pull per gear change is shorter, requiring higher precision and more adjustment.

The news that 10 speed is filtering down to all the "quality" groupsets Tiagra upwards, is bad news for tourists and commuters. We either have primma donna kit that only works when you put a bunch of roses and some chocholates in the dressing room, or we have cruder low-end kit.

daveizdum

Keep in mind that, a few years ago, people were using 3x7 and 3x8. But now a lot of people are using only two rings up front, so they have 2x10 or 2x11. For them, the total theoretical number of gears isn't increasing.

Bill Kapaun

I use a 14-25 during cold weather (all bundled up) and a 12-23 for warm weather (9 speeds).
My riding is virtually flat and I only use the middle ring around town. (<=6 blocks between traffic lights generally)

Thing is, with my emphysema, I need to maintain a rather specific cadence or else run out of breath.
Having the very close ratios allows me to maintain this while making small changes for head/tail winds or slight changes in slope. Kind of like a semi truck.

w98seeng

Thank you everyone for the helpful info. I understand now and will use it to pick the best cassette I can for the type of riding I do. I'm going with a...

Ian

Al1943

Right answer.
When riding with others, especially drafting in a pack, a cassette with more cogs and closer ratios alloys the rider to match speeds with others while maintaining a more efficient cadence. This has been found to be in the 90 to 110 rpm range.

w98seeng

For me I think it would be in the 90 to 110 rph range.

operator

The only people who don't think more gears is good is retrogrouches. More gears means less jump between gears and more gears in total for a wider gear range. It let's you ride your bike more and worry less about, honestly dumb things like gearing.

We're already getting to the point with 11s systems, that I think we're starting to push it in terms of cable operated systems. Hangers have to be off by < 1mm. Cable systems have to be cut and setup perfectly, and even minor contamination of lines results in poor shifting.

Electronic is the future.

****ing retrogrouches should go back to chopping wood and rubbing sticks together to build fires. Seriously. WTF.

Monster Pete

Just because something is new doesn't make it better. More gears is good up to a point, after which the increased precision needed for reliable shifting, along with the reduction in durability from thinning the chain and sprockets to cram another one in there just isn't worth it for the non-racing cyclist IMHO. Once there is the need to have electronic shifting or readjust the cable every time the bike gets wet or slightly muddy, that's when things get a bit ridiculous for what is really quite a simple machine. However, another sprocket is bragging rights for the manufacturers who will naturally try to keep up with their competitors, so the n+1 trend will probably continue.

I think eventually there will be a gap in the range, with racers using 10/11/12/etc cassettes for the closely spaced gears, utility and mountain bikes using 5/6/7/8 speeds for the durability, with little demand for 9.

The ideal of course would be a CVT. I can see this working with a belt drive and variable diameter pulleys front and back of the double-cone type. You could either adjust it manually with a friction shifter or arrange it automatically according to cadence. However, if you're gram counting it's not likely to be an option.

Yellowbeard

"Duplicate gears" is kind of a nonsense criticism. It only applies if you judge a drivetrain by the overall number of speeds rather than any meaningful description. If anything, duplicate gears are a good thing because they give you more options for smooth shifting patterns and let you avoid cross-chaining. Besides, "duplicate gears" result from close chainring ratios, not the alleged arms race going on at the rear cluster. If you want to eliminate duplication you'll have to shift across practically the whole cassette every time you shift the front if you want to make any kind of smooth transition.

*Edit: or I guess you could use half-step gearing.

w98seeng

I think someone needs a hug...

frantik

... speaking of grouches

frantik

yeah, CVT are cool but pricey.. if i were rich i'd build up a bike around one https://www.sheldonbrown.com/harris/nuvinci.html

Burton

More is only better if its actually practical and functional. A case in point would be some of Kona`s new flagship dual suspension models. Shifting to the smallest front chainring only gives you access to TWO gears on the rear cassette before the chain starts dragging on the front derailleur crossover bolt. On bikes that cost from $3,000 to $5,000 I expect more and if this is the kind of `progress` that consumers will have to deal with - call me a retrogrouch!

frantik

yeah that is one thing i've notice on indexed gearing with wide cassettes... the chainlines can really limit your gear choices

i just ride recreationally.. 2x7 is fine for me.. though i do live in flatland