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Old 09-02-10, 01:07 PM   #1
HiYoSilver
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Why do pro's have all the fun? New engineering plea [long]

Why can't SRAM and Shimano design a gruppo that would allow regular
riders to have as much fun as pros?


I don't know about you all but I'm getting pretty tired of cycling companies
ignoring the needs of cyclists. I'm buying a new bike and spending way way
too much. Bottom line is it boils down to gearing options are simply not
available. Nothing has changed in the last four years as I have been considering
different bikes. It's still a situation of choosing between bad and worst.
With the change from 9 speeds to 10 speeds the choices are now
between WORST and MUCH WORST.

This is improvement? Negative!! Not for the rider, just more profit for the cycling companies.

What are the recent changes that lead to this sorry of affairs?
Dynamic one seems to be the desire for these companies to reduce their offerings
and so they have been pushing the double and especially the compact double
as a replacement for a triple. Dynamic two is the change from 9 speed cassettes
to 10 speed cassettes.

Overview of the impact
With SRAM's new 11-32, they can come close to the gearing range of a stock triple.
However the cost is a heavy toll on shifting timing and rider dropping out of desired
cadence range to a lower effective range. Naturally as the rider works to return to
their natural range, there will be a spike in power generated and a decrease of
energy reserves. This impact is worst because with the old 9 speed triples it was
not difficult to swap out chainrings to obtain the ratios desired. With the new 10 speed
compacts, you can't swap out the lower ring for a smaller one. Best case you lose
at least 2 low end gears available on the triple.

Details of impact -- gruppo range
---Small ring
Compact's lowest is 32gi {gear inches**, range for ring 32..83gi {w/ 11.28**
Triple's lowest 24gi, 2 lower gears than compact, range is 24..53gi {w/ 24x 12.27**

---Middle ring
Compact- removed
Triple-- range is 42..93gi {w/42 x 12.27**

---Large ring
Compact's highest is 121gi, range 48..121gi {w/ 11.28**
Triple's highest is 120gi, range 53..120gi {w/ 54x 12.27**

So at first glance this looks good. The range for the large chainrings is about the
same. The range for the small compact and the middle triple are about the same.
The problem in ranges occurs on the uphill climbs and the windy conditions.
Not all of us are pros who can just power on and burn watts to keep on going.


Details of impact -- change in rider effort
This aspect seems to have been completely overlooked, or companies choose not to discuss.
Measure method is the percentage change in GI as move from one gear to a higher gear,
i.e. want to go faster so chose a lower toothed cassette. The standard is taken from existing
road cassettes. I don't have a power meter so don't have the watt impact of a change,
and it would be an interesting experient for someone to test these and see how much
of a watt impact is caused by different percentages of GI changes. Anyway, definitions:

easy shifting = less than 10% GI change between gears
moderate shifting = between 10% and 12% GI change between gears
hard shifting = greater than 12% change between gears

Compact Crankset results
Easy 4, upper gears
Moderate 2, lowest and middleish gear
Hard 3, mid and lower gears

Triple Crankset results
Easy 5, upper gears
Moderate 3, middle and lowest
Hard 1, second from lowest


Here's a comparison with 39t chainring
cassette -- range -- change percentage when moving to a higher {lower number** cogring
11.21 50 95 A-10.5 B-5.6 C-5.9 D-6.3 E-6.7 F-7.1 G-7.7 H-8.3 I- 9.1
12.27 38 87 A-12.5 B-14.3 C-10.5 D-11.8 E-6.3 F-6.7 G-7.1 H-7.7 I-8.3

Note for rings C & D the difference. Best cassette gives roughly a 6% change while
the average cassette gives more than an 11% change. Basically you lose a gear choice
and gearing changes are twice as hard.

What is most bizarre with the current engineering is it does not matter much if you choose
any double or a triple. After you run the numbers on the gears, you only have 15 to 16 effective gears available. {Effective means not duplicate and gear change percentage more than 3%**


On the path to a better solution
Why not use a cassette that is already available, the 11-21?
Look at the smooth shifting
Easy 9, most gears
Moderate 1, lowest gear only
Hard 0, does not happen

Why not provide an honest 30 effective gears to cyclists?
Inner of 16t for range of 20-39 GI
Middle of 31t for range of 30-75 GI
Top of 53t for range of 67-129 GI

A double of this middle and top would serve most cyclists. Those needing
more friendly gearing because of experience level/age/physical health/steep terrain riding
could use a triple which just adds the lower ring.
Worst case engineering should be able to create a low ring of 20t as they already
do that for mountain bikes. That would still supply a range of 25-48GI.

Naturally the engineering challenge will be to handle the range of 36 teeth between
inner and top chainring. Perhaps they need to review the solutions of the recumbent
makers to see what they could apply to road technology.


Advantages for cycling suppliers
-- won't lose as many customers who give up because "shifting is too hard"
-- new products to sell
-- only two cranksets instead of current 4 or 6 sets
-- fewer resources spent on a variety of cassettes
-- potential of merging mountain and road cranksets
-- with only a double or triple crankset, derailers & shifters should be able
to be designed to work on both, so lower costs.

Disadvantages for cycling suppliers
-- initial investment in engineering
-- have to create a new marketing name for this gruppo

Advantages for cyclists
-- double the number of effective gears
-- compatibililty between doubles and triples
-- gruppo will work with any bike, including all tris
-- won't have to continually accept bad or worst solutions
-- will be able to attack the steepest hills, even when tired
-- won't struggle and lose pacing when shifting to faster gear
-- won't struggle and lose momentum when shifting to slower gear
-- should be able to ride faster
-- should be able to ride longer

Disadvantages for cyclists
-- will feel the "need" to buy a new bike
-- if stay with current setups, will suffer more than those with new setups
-- can't argue as much about gearing and will have to focus on training
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Old 09-02-10, 02:41 PM   #2
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Wouldn't it be really hard to go from 1/10 to 2/1 and 2/10 to 3/1 in this "honest 30 effective gears"?
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Old 09-02-10, 03:11 PM   #3
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I'm having lots of fun now and had lots of fun on my single-speed cruiser. It's not all about the gearing.
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Old 09-02-10, 03:34 PM   #4
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Originally Posted by tligman View Post
Wouldn't it be really hard to go from 1/10 to 2/1 and 2/10 to 3/1 in this "honest 30 effective gears"?
Opps, made a mistake. I didn't run the numbers but only looked at the ranges. 27 gears, but that's still better than the 16 with a triple. Here's the data:

---------------------------------------------------------------------------

SP Shifting Pattern
CRxFW ChainRing x FreeWheel
GI Gear Inches
GIdf Percentage of increase between present GI value and the
next sequential GI value.
DI Distance traveled in INCHES in a single pedal rotation
diff Difference in INCHES between the present DI value and
the next sequential DI value.
DF Distance traveled in FEET in a single pedal rotation
displayed as FEET' INCHES.decimal_remainder"
PRPM Pedal Rotations Per Mile
RT Gear Ratios

Wheel Diameter: 26.70 inches
Gears: 16/31/53 11-12-13-14-15-16-17-18-19-21
---------------------------------------------------------------------------
SP CRxFW GI GIdf DI diff DF PRPM RT
---------------------------------------------------------------------------
1> 16x21 20.34 10.53% 63.91 6.73 5' 3.91" 991.41 1:0.76
2> 16x19 22.48 5.56% 70.64 3.92 5'10.64" 896.99 1:0.84
3> 16x18 23.73 5.88% 74.56 4.39 6' 2.56" 849.78 1:0.89
4> 16x17 25.13 6.25% 78.95 4.93 6' 6.95" 802.57 1:0.94
5> 16x16 26.70 6.67% 83.88 5.59 6'11.88" 755.36 1:1.00
6> 16x15 28.48 7.14% 89.47 6.39 7' 5.47" 708.15 1:1.07
7> 16x14 30.51 7.69% 95.86 7.37 7'11.86" 660.94 1:1.14
8> 16x13 32.86 8.33% 103.24 8.60 8' 7.24" 613.73 1:1.23
9> 16x12 35.60 10.71% 111.84 11.98 9' 3.84" 566.52 1:1.33
10> 31x21 39.41 10.53% 123.82 13.03 10' 3.82" 511.70 1:1.48
11> 31x19 43.56 5.56% 136.86 7.60 11' 4.86" 462.96 1:1.63
12> 31x18 45.98 5.88% 144.46 8.50 12' 0.46" 438.60 1:1.72
13> 31x17 48.69 6.25% 152.96 9.56 12' 8.96" 414.23 1:1.82
14> 31x16 51.73 6.67% 162.52 10.83 13' 6.52" 389.86 1:1.94
15> 31x15 55.18 7.14% 173.35 12.38 14' 5.35" 365.50 1:2.07
16> 31x14 59.12 7.69% 185.74 14.29 15' 5.74" 341.13 1:2.21
17> 31x13 63.67 8.33% 200.02 16.67 16' 8.02" 316.76 1:2.38
18> 31x12 68.98 7.98% 216.69 17.29 18' 0.69" 292.40 1:2.58
19> 53x19 74.48 5.56% 233.98 13.00 19' 5.98" 270.79 1:2.79
20> 53x18 78.62 5.88% 246.98 14.53 20' 6.98" 256.54 1:2.94
21> 53x17 83.24 6.25% 261.51 16.34 21' 9.51" 242.29 1:3.12
22> 53x16 88.44 6.67% 277.85 18.52 23' 1.85" 228.03 1:3.31
23> 53x15 94.34 7.14% 296.38 21.17 24' 8.38" 213.78 1:3.53
24> 53x14 101.08 7.69% 317.55 24.43 26' 5.55" 199.53 1:3.79
25> 53x13 108.85 8.33% 341.97 28.50 28' 5.97" 185.28 1:4.08
26> 53x12 117.93 9.09% 370.47 33.68 30'10.47" 171.03 1:4.42
27> 53x11 128.65 0.00% 404.15 0.00 33' 8.15" 156.77 1:4.82
---------------------------------------------------------------------------
SP CRxFW GI GIdf DI diff DF PRPM RT
---------------------------------------------------------------------------
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Old 09-02-10, 06:07 PM   #5
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You need to ride more, and calculate less.

My crank runs 44-32-22, and I've run both 11-32 and 11-26 cassettes (yes, MTB); for commuting, the 11-26 was sweet, but for the silly stuff I'm getting more into (again), the 11-32 will have to stay.

Personally, I have so much fun pedaling, I don't bother thinking too much about what gears are 'most efficient'.
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Old 09-02-10, 07:45 PM   #6
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you are overthinking this...
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Old 09-02-10, 07:51 PM   #7
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.........feeling dizzy...........need to try a different post-reading gear......................25 gear itches might work
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Old 09-02-10, 08:07 PM   #8
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Quote:
Originally Posted by DX-MAN View Post
You need to ride more, and calculate less.
Personally, I have so much fun pedaling, I don't bother thinking too much about what gears are 'most efficient'.
What I was thinking, too. I know a lot of people get into gear inches, but from my standpoint, this is about the most boring thread i've ever seen.
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Old 09-02-10, 08:21 PM   #9
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Just because of this thread, I'm going to ride my old 10-speed tomorrow (meaning 2x5, not 2x10 or 3x10).
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Old 09-02-10, 09:04 PM   #10
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Quote:
Originally Posted by DX-MAN View Post
You need to ride more, and calculate less.
My crank runs 44-32-22, and I've run both 11-32 and 11-26 cassettes (yes, MTB); for commuting, the 11-26 was sweet, but for the silly stuff I'm getting more into (again), the 11-32 will have to stay.

Personally, I have so much fun pedaling, I don't bother thinking too much about what gears are 'most efficient'.
+1

I run a mtn bike chainring and cassette on my road bicycle. I'm actually not sure what my chainring setup is (46-36-26, I think) but we're talking about changing the 26 out to a 22. And my cassette is an 11-32. That's one of the beautiful things about cycling. You can ride whatever equipment you want to ride.
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Old 09-03-10, 04:40 PM   #11
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Advantages for cycling suppliers
-- won't lose as many customers who give up because "shifting is too hard"
The common complaint is that the customer can't figure out how the relationship between the front and rear DRs (large ring in the front is hard, large ring in the back is easy). Your solution will add more complication.

In asking for 30 (or 27) effective gears you are asking the manufacturer to eliminate cross chaining + a re-design of the RD cage (able to handle large-large and small-small front and rear gear combos). This would take a fundamental re-think of the entire drivetrain. The only option that comes close are internally geared hubs.

Quote:
With SRAM's new 11-32, they can come close to the gearing range of a stock triple.
However the cost is a heavy toll on shifting timing and rider dropping out of desired
cadence range to a lower effective range. Naturally as the rider works to return to
their natural range, there will be a spike in power generated and a decrease of
energy reserves.
Another fundamental (marketing) issue: Why is the casual rider concerned about their power output? They will just go more slowly, problem solved.
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Old 09-03-10, 06:29 PM   #12
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You mean bikes can have more than 6 cogs in the back!

I have a bigger problem with lacvk of compatibility between mfgs and planned obsolecence.
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Old 09-03-10, 06:35 PM   #13
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Wait, why exactly would having more (than my current 12) gears allow me to have more fun?


[k]
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Old 09-04-10, 04:10 AM   #14
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A lot of cyclists have a lot of fun with just one gear.
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Old 09-04-10, 07:10 AM   #15
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Just get a NuVinci.
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Old 09-04-10, 10:30 AM   #16
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I love my Rohloff hub, It s an oil bathed internal gear hub. with the gear ratio range of a mountain bike in 14 steps.

and the 6 speed on my Brompton is nice too, they are similar in that a planetary gear set
in the hub is used twice in 2 different ranges, the low range starts back thru the high gear ,
though where the Rohloff engineers that to all happen in the hub, 7 speed x 2,

with my Sturmey Archer 3 speed in the back, and the Mountain drive 2speed planetary gear in the crank
I do that with a tap of the heel , center button on the crank,
and a flick of the trigger shifter ..
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Old 09-04-10, 10:39 AM   #17
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How many is besides the point, the ratios and the range of those ratios is what counts ,
so, with a focus on having more 'gears' , a lot of ratios are redundant or nearly So.

remember the Pros are the tools of the teams and the sponsors to wear the advertising brands
and try out the new stuff the component corporation engineers design,
those corporations are in a competiton for the Eyeballs and wallets of every one else in the world watching...

to convince them that they Need a new bike with the latest Widget scheme.
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Old 09-05-10, 12:13 AM   #18
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Ride your way and model for the rest of us.
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Old 09-05-10, 12:21 AM   #19
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Am waiting for the new Alfine 11 speed IGH... can get a nice 25-95 gear inch range with a single chain ring which is what most folks are going to find useful for their day to day riding, commuting, and it should be especially nice for touring and people who ride small wheeled and folding bicycles.

With derailleur bikes I don't think many people need more than a 7 speed and a well chosen double and for many, a single would do.
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Old 09-05-10, 12:27 AM   #20
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I run bikes with 1, 3 (IGH), 8 (2x4), 12 (2x6), 21 (3x7), and 24(3x8) speeds and still don't have a 9 speed in the house... my new wheel set on my touring bike will use a 7 speed with a touring triple.

Can't forget this... my tandem runs a 4 by 8 so has a 32 speed drive.
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Old 09-07-10, 10:29 PM   #21
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Yuck! A triple with a 16 tooth granny would shift horribly. The smaller gears in your setup would also wear out faster.

Your premise is completely backwards - the professionals and racers are the only ones who need such tightly spaced gears. The rest of us are perfectly happy to pedal a little slower or faster cadence than optimal rather than constantly shift between tightly spaced gears. Beginners are the ones who benefit the most from lower range gearing and they tend to shift as little as possible.
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Old 09-07-10, 11:49 PM   #22
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my Brompron Got a mountain drive Crankset , single chain-ring , 2 speeds,
2nd one is a planetary, [6 gears in total]
chain stays on the one chainring, in low range crank turns faster than the chainring.

If I had a 40t chainring , the low range would work like it's a 16t..

but since the wheel is 16", the chainring is a 54t so the low is like a 21.6t
and with the 15t cog on the 3 speed low gear, in low range is like 17",

almost 1:1 with the wheel size.. unicycle gearing..

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Old 09-08-10, 02:30 PM   #23
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HiYoSilver;

I would love it if you could be forced to ride your suggested gearset and see how bad it is.

The 9-10 shift and 18-19 shifts, either direction, would be monsters as you need to shift across 8 cassette sprockets to reach the next gear. By the time you do you have slowed down too much so need to shift back. Also the gear steps are too close together, particularly in the lower gears where the rider can easily handle larger gear steps.

Get a copy of Frank Berto's 1988 book called Bicycling Magazine's Guide To Upgrading Your Bike. Usually available used on Amazon. It has an excellent chapter on gearing and discusses gearing ideas similar to yours, and their problems.

The 16-31-53 front rings would give very poor shifting on to the middle ring as they exceed any front derailleur capacity limits. The total range of 46 teeth also exceeds rear derailleur takeup capacity and your gearing scheme ignores rules about not cross chaining. A design that looks pretty on paper can be a total disaster when ridden. IMO yours is a perfect example of such a design.

From a rider convenience and ease of shifting standpoint duplicate gears and minimizing shift time at the rear when going between chainrings is the way to go for a derailleur system. In the days of 5 rear sprockets many loaded touring bikes used a setup with minimal duplicate gears. It was called "Half Step + Granny" gearing. It required a lot of double shifts if used as intended. Again well covered in the above mentioned book. If you want to eliminate duplicate gears and have a wide gear range then get something like the Rohloff IGH Hub.
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Old 09-08-10, 04:27 PM   #24
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Quote:
Originally Posted by HiYoSilver View Post
Why can't SRAM and Shimano design a gruppo that would allow regular
riders to have as much fun as pros?

I've dropped fewer chains this season than Andy Schleck.

I win.
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Old 09-10-10, 01:49 PM   #25
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Quote:
Originally Posted by Greg_R View Post
In asking for 30 (or 27) effective gears you are asking the manufacturer to eliminate cross chaining + a re-design of the RD cage (able to handle large-large and small-small front and rear gear combos). This would take a fundamental re-think of the entire drivetrain. The only option that comes close are internally geared hubs.
Agreed, except for the cross chaining. I don't care how they design it. I would just like a full range of gears
and smooth transitions between gears without taking a horrible impact on pacing.
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