WVU_Engineer

I looked it up, it is a pretty good looking bike. As far as the speeds go, I thought the same thing, but I calculated all of the ratios out and the 21 speed version of my venture only had two speeds outside of the range that my 7 speed version has. One of those speeds was only very slightly outside of the range too, so really there was only one speed out of all of those not covered by my 7 speeds. There is also a lot to be said for simplicity.

dynaryder

That make no sense. Are you talking about these bikes?
Raleigh Bicycles Venture - 2013 Lifestyle
Raleigh Bicycles Venture 3.0 - 2013 Lifestyle

They have the same freewheel,but the 21 has three rings.
Sheldon Brown's Bicycle Gear Calculator

The 7spd has a range of about 30.3-73.6",the 21 has about 21.2-88.3". That's a huge difference,esp on the lower end.

WVU_Engineer

Hopefully the formatting holds, I didn't include tire size in the calculation because both bikes have the same tire size. As you can see only the 34/28 combination and the 48/14 combination are outside of the range (ok the 48/16 is out by a hair). Having used the 40/34 combo even going up a hill in mushy dirt it feels like the chain has fallen off the bike.

[TABLE]
[TR]
[TD="width: 86"]Venture[/TD]
[TD="width: 86"][/TD]
[TD="width: 86"][/TD]
[TD="width: 86"][/TD]
[TD="width: 86"]Venture 3.0[/TD]
[TD="width: 86"][/TD]
[TD="width: 86"][/TD]
[/TR]
[TR]
[TD]40[/TD]
[TD]Tooth Crank[/TD]
[TD][/TD]
[TD][/TD]
[TD]28[/TD]
[TD]38[/TD]
[TD]48[/TD]
[/TR]
[TR]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD][/TD]
[TD]Ratio[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD]Ratio[/TD]
[/TR]
[TR]
[TD]14[/TD]
[TD]0.35[/TD]
[TD][/TD]
[TD]14[/TD]
[TD]0.50[/TD]
[TD]0.37[/TD]
[TD]0.29[/TD]
[/TR]
[TR]
[TD]16[/TD]
[TD]0.40[/TD]
[TD][/TD]
[TD]16[/TD]
[TD]0.57[/TD]
[TD]0.42[/TD]
[TD]0.33[/TD]
[/TR]
[TR]
[TD]18[/TD]
[TD]0.45[/TD]
[TD][/TD]
[TD]18[/TD]
[TD]0.64[/TD]
[TD]0.47[/TD]
[TD]0.38[/TD]
[/TR]
[TR]
[TD]20[/TD]
[TD]0.50[/TD]
[TD][/TD]
[TD]20[/TD]
[TD]0.71[/TD]
[TD]0.53[/TD]
[TD]0.42[/TD]
[/TR]
[TR]
[TD]22[/TD]
[TD]0.55[/TD]
[TD][/TD]
[TD]22[/TD]
[TD]0.79[/TD]
[TD]0.58[/TD]
[TD]0.46[/TD]
[/TR]
[TR]
[TD]24[/TD]
[TD]0.60[/TD]
[TD][/TD]
[TD]24[/TD]
[TD]0.86[/TD]
[TD]0.63[/TD]
[TD]0.50[/TD]
[/TR]
[TR]
[TD]34[/TD]
[TD]0.85[/TD]
[TD][/TD]
[TD]34[/TD]
[TD]1.21[/TD]
[TD]0.89[/TD]
[TD]0.71[/TD]
[/TR]
[/TABLE]

dynaryder

Where are you getting those numbers from?

I've put alot of miles on my bikes in a very hilly area,and I can tell you that not only can I tell the difference between a 40t and 48t ring when going up and down steep hills,but there's a huge difference between a 28t and a 40t. IOW,your numbers do not jive with my real world experience. I did most of my commuting on bikes with either a 3x8 or 3x9 drivetrain. I used a 2x10 with a 36/28 granny for a while,but that was a lightweight bike,and it wasn't always pleasant climbing up the big hill. I tried a bike with an 8spd IGH and one with a 9spd IGH,but neither had a comfortable range. I would never consider commuting on a 1x setup(with the exception of SRAM's XXI,which is really a different animal). 1x's are fine for flattish areas,but suck in hilly ones.

When it comes to going up and down big hills,there is a huge difference between a 1x and 3x setup.

WVU_Engineer

The numbers come from dividing the number of teeth on the flywheel cog by the number of teeth on the crank cog. So if the ratio is 0.5 it means you turned the crank a half of a revolution for each revolution of the rear wheel, a ratio of 1 would mean that you turned the crank one revolution and your rear wheel completed one revolution. This of course assumes that there is no freewheel action.

This is the mega range freewheel that makes a jump from 24T to 34T between 2nd and 1st gear. I can tell you that I am 290 lbs and have only been biking for a month and the only place I have used the lowest gear is on a long steep hill and even then I could have done it in 2nd.

Surprised that on a 21 speed setup there are only 3 outside the range of a 7 speed setup? I know I was.

Math never lies, but our brain does it to us all the time.

By the way, the freewheel on the venture is not listed in the options in Sheldon Browns calculator so I am not sure which one you used.

DorkDisk

your math is wrong. A large chainring and small cog will turn the wheel multiple times per revolution, not less - and vice versa.

WVU_Engineer

That is what I said above, re-read it.

ocelotito

I made similar calculations between the two Treks I am considering (shift 1 and 2) and the results were similar to what you got. I don't want to be held back and regret not having more options, but on the other hand, I am afraid that any advantage with the additional gears will be lost with the heavier, non locking suspension. And I haven't tried the one with suspension, maybe it will not feel as great as the one I tried? The difference in price between the two bikes is $100. I'll go to try it out again for a longer ride.

DorkDisk

I misunderstood your personal measurement of gearing that no one else in the cycling community uses.

Youre counting gears instead of calculating range and are influenced by the much hated Megarange cassette with its cadence killing 10t jump. Only one gear on the table but a 28x34 is worlds apart from a 40x34. Normal cassettes will have a 1-3t gap on average across the range. Make it a 10sp cassette and count the gears - if it matters.

But youre right in general. Triple setups have a lot of redundant and unusable gears

WVU_Engineer

I am new to the bicycle community, I was presenting my calculations the same was an automobile transmission would be presented.

I find that lowest gear, with its 10T jump, useful as a last resort.

DorkDisk

Welcome to cycling. We do things differently. We are men in tights and ballerina shoes, wearing nylon shirts with logos of european floor tiling and other household goods manufacturers. And we dont use car gearing measurements

Little Darwin

First, I agree that numbers don't lie.

Let's look at the lowest gears in each case, comparing 40x34 and 28x34

While the resulting ratios seem close, 0.85 & 1.21 since it is only off by less than 0.4... if you divide 0.85 by 1.21 you get 68% So, if you were in college, and 1.21 represents a perfect score, 0.85 would be 68%, and would result in a failing grade. Do you see how the same degree of difference could make a big difference in climbing hills? In terms of climbing, each pedal stroke goes only 68% of the distance. This is emphasized by the fact that the difference between each of the gears using the same chain ring, only amounts to a couple of hundredths difference...

You need to look at more than raw gear ratios and think that a small decimal difference is not significant. You need to look at the relationship between them, and determine the actual power needed to accomplish the task.

As another example of how raw numbers can be misleading if viewed in a vacuum... The amount of energy needed to get to the top of a hill is the same regardless of gear ratio. It is strictly based on weight being lifted a certain number of feet. Based on this fact, gearing on a bicycle is completely irrelevant. I leave it as an exercise in elementary physics to determine how gearing helps at all. But, we do seem to agree that gearing is beneficial... it is just that for some of usneed (or like) the additional gearing options, even if you don't.

ocelotito

The numbers of the ones I saw are very similar to these. Just like with this one, only one gear combination is vastly different. Is that worth paying $100? Unfortunately the inventory has been low and I haven't been able to test the bikes back to back. There is a gentle slope by the store that I could try. I'm also worried about the shift 2 non locking suspension. I've read negative aspects of suspension in bikes that will be used in pavement. The pavement where I live is bad in some places, but I guess the fat tires will help. I rode my Myka (mountain) for years, not knowing that the whole time the suspension was locked . It never bothered me.

dynaryder

I'm not,I've been riding for years in a very hilly area. I've done my commute on 3,7,8,and 9spd IGH's,as well as 2x9,2x10,3x8,and 3x9 setups.

You should know as an engineer that in theory,there's no difference between theory and practice. But in practice,there is. You're talking calculations,I'm talking real world experience. Your calculations of only a small difference between a 1x and 3x setup do not bear out in the real world.

You're in Southern MD,come up here to DC. We'll go to Loughboro or Mass or Wisc. I'll let you ride up and down them on your 1x7. Then I'll let you do it on one of my 3x9's. You'll notice a difference in how fast you have to spin going downhill,and a world of difference in how easy it is to climb.

Didn't use the pull down. Since we're talking about range and not specific gears,I just put 14 and 34 in the Custom Sprocket line.

WVU_Engineer

Going somewhere much hillier than DC is in a few weeks. What are the cog sizes in your 3x9?

Around here I only seem to use gears 2-5, I used 6th once but I was going faster than I feel comfortable going so I shifted back to 5th. I think that the 14-28 freewheel would be more useful for me, so when mine needs replaced that is probably what it will get replaced with.

WVU_Engineer

My whole point was the 21 speeds vs 7 sounds huge, but due to the overlap is isn't anywhere near as much of a difference as it sounds.

dynaryder

48/38/28 and 48/36/26,both with 11-34 cassettes.

Then you wouldn't like DC. I can spin out 48/11 going down Embassy Row.

WVU_Engineer

That sounds like you are hauling some ass. I don't trust the bumper car drivers of the MD/DC area enough to even like riding on a road where I could do that, heck sometimes I don't like driving a car around here.

Little Darwin

I think the number of gears is sometimes clouded by not discussing the way they are used.

In the way I use a triple, it is not about number of gears. I see it as more like a 4x4 truck's High/Low option in some trucks (only with an additional extra-high 3rd choice).

I rarely shift the front. Over 90% of the time I am in my middle ring shifting the rear as appropriate... The proportion would change if I didn't spend the majority of my time on rail trails and flat roads. When I approach a significant hill, I do a double shift, and shift the front to my small ring (the low range), and go up a gear or two on the cluster so that I don't spin out. I then use the rear to keep me in a good gear for each phase of my climb. As I crest the hill, I am back to the middle ring (my high range), unless there is a down hill that I want to fly down, and then I might pop into the big ring (my extra-high range).

So, for the real world, it is irrelevant that there are gears that are identical or similar in different ranges, as long as I have the 8-10 in each range to rely on when I am in each of the three independent ranges.

dynaryder

I ride with traffic.

ocelotito

It surprised me too. I really expected a much bigger difference.