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The fun and games of bicycle gearing

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The fun and games of bicycle gearing

Old 12-16-20, 11:42 AM
  #76  
mack_turtle
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never underestimate the ability of BF readers to tell others that their subjective preferences are wrong.
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Old 12-16-20, 12:25 PM
  #77  
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Originally Posted by cyccommute View Post
Yes, it is a good analogy.
No, it's not. You should let it go.

But my point wasn’t to say that compact doubles are like half-steps. They are only like half-steps in that there is a lot of extra...and unnecessary...shifts when compared to a traditional triple system. The half-step requires a front and rear shift on every shift to make them useful. At least the compact double only require a downshift and a double (or triple) upshift.
No wonder you didn't like a half-step setup – you didn't know how to use it. You don't shift the rear derailleur with every front shift.
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Old 12-16-20, 12:55 PM
  #78  
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Originally Posted by Amt0571 View Post
How about if you get around the fact that there's not a huge gap if you shift correctly? I don't hunt for gears, I just shift. And if I have to shift the rear at the same time that's a non issue. I do that with triples too as the gap is still bigger than the gap between the sprockets.

Frankly, I don't see any issue with the system. It's like if people were complaining because they have to press the clutch to shift in a manual car.
If there isn’t a huge gap between the chain rings, why do you have to upshift after a downshift? No gap (or smaller gap) and there’s no upshift.

I have designed a 9 speed triple system that has exactly the same steps between the gears on the back and the cassette...at least with the outer two rings.. It’s not all that hard to do. A 50/42/30 or 48/40/30 with an 11-34 cassette will do the job. A shift on the big ring and the rear cassette or a shift from the outer ring to the middle ring would be close enough to the same that the rider would feel any difference. It’s got a slightly wider range than the compact double without the double shift. The one proviso is that the inner ring wouldn’t be close. Increasing that ring to a 34 would make the whole range work but the low end would be sacrificed.

Originally Posted by tomato coupe View Post
No, it's not. You should let it go.
Yes, it is. Perhaps you should follow your own advice.


No wonder you didn't like a half-step setup – you didn't know how to use it. You don't shift the rear derailleur with every front shift.
You shift the front and rear at the same time often enough that is is a difficult system to master and, frankly, not worth the effort...just like compact doubles. It also doesn’t work all that well for a wide range gearing system.
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Old 12-16-20, 01:28 PM
  #79  
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I'm a 3X guy. I love my old racing gearing (53-42 X 13-19 5-speed) except as a non-racer, I need more lower gears. When I finished racing, I retired the race bike and ordered the Mooney to run the exact same gears only with an additional 28 tooth inner chainring. As more cogs became available, I simply added bigger ones. 40 years later I moved my front cogs down some to 50-38-24. Up to 9-speed and 28 in back. (If I don't need the 28, I go 25 or 23 and have one or two fewer two tooth jumps.)

Granted I am a dinosaur,but I still use DT shifting. It works for me; really well. Light, cheap, reliable, crash-proof and universally adoptable to any cassette or FW wheel. And double shifts? Easy with one hand. (Even easier on my best bike because I use the DT shifters that mount on the box on top of the tube. I do this to keep the levers away from my knees.)

One thing that would bug the heck out of me with a standard 1X - doing the big dump down a bunch of cogs and not being able to do it on one sweep of the shifter. Click, click. click ...? Nay. I'll stay a dinosaur.
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Old 12-16-20, 02:04 PM
  #80  
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Another advantage of the 1x system, especially SRAM's implementation, is that it makes dealing with the chain a lot easier. You can lock the RD open and pull the chain right off the ring. When you put it back on you don't need to pull it through the FD and around the front ring and hold tension on it while you're doing up the link while it's trying to unspool onto the floor. You just drop the chain through the RD and do up the link, drape it on the ring, undo the lock
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Old 12-16-20, 02:13 PM
  #81  
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Combine 1x with a DT shifter and you can do the whole lot, end to end, in one go.
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Old 12-16-20, 04:37 PM
  #82  
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Reading this discussion regarding gears shifting reminded me of a YT video I've once seen that showed shifting three transmissions without gear synchronization in big trucks. No idea if modern trucks made that easier but it is real eye opener. After that, my old classic friction DT shifters seem a peachy proposition, even with having to compensate and overshift while easing on the pedals, all that stuff.

On one of my favorite ride circuit, there is quite a fast downhill that ends on a bridge over a creek immediately followed by a very steep uphill that forces you to shift to very low gear very fast (in my case, to the second lowest gear). I dropped chain twice on that uphill and shifting more carefully comes at the expense of not negotiation that road section as fast as I could if... well, I got more modern bike now, mechanical indexed shifting, but still expect to drop chain anyway when I take it on that road (come next spring) since even the best tech out there still does drop chain in some situation and this situation virtually calls for it, if any.
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Old 12-16-20, 04:55 PM
  #83  
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Originally Posted by Racing Dan View Post
Combine 1x with a DT shifter and you can do the whole lot, end to end, in one go.
Except with a 1x11 or 1x12 you’ll be doing 360’s with the shift lever...lol!

Well maybe not literally, but my old retrofriction covered a lot of ground with just 7 speeds.

John
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Old 12-16-20, 07:08 PM
  #84  
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This thread makes me glad I switched to fixed gear.
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Old 12-16-20, 07:47 PM
  #85  
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Originally Posted by mack_turtle View Post
never underestimate the ability of BF readers to tell others that their subjective preferences are wrong.
Yup.

I'm not gonna argue about it any more. I respect cyccommute for his many helpful posts, and I'm glad he has a gearing setup that works for him. My double chainring setups (one standard, two compact, one sub-compact) all work well for me. It's nice to have so many choices to accommodate different people's preferences.
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Old 12-18-20, 11:25 AM
  #86  
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Going back to post #1. The primary purpose of 1X is to eliminate chain drops that can occur when riding on rough terrain. Flatland riders may also find that 1X has enough gear range for their limited needs. The latest 2x12 drivetrains, like I have, only have about 15 distinctly different gear ratios and all the rest are just overlapping ratios. I rarely make more than a 2 sprocket compensating shift after a chainring shift. Someone posted a way to get 18 ratios, but it required a ridiculous 5 sprocket shift and a chainring shift that you'd have no way of knowing when to make without a bike computer with a sprocket display to go by.

What has improved is total gearing range. My old 53/39/28 triple with a 12-25 or 13-29 10 speed worked fine, but my latest 12 speed drivetrain with a 46/30 crank and 10-36 cassette has a lot more range. It's got more top gear and more low gear. Total range of the old system was no more than 422% while my new system has a 552% range. The sprocket spacing is also better suited to climbing slopes in the 6-12% range. I sometimes miss having a 14T sprocket, but it hasn't been a big deal. Campy may offer a 10-11-12-13-14-16-18-20-23-27-31-36 twelve speed cassette with better spacing than the SRAM 10-36, sometime in the future, since they've opened the door to smaller sprockets with the new Ekar 13 speed. There might be a 2X13 system in the future too.

https://www.campagnolo.com/US/en/Com...peed_sprockets
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Old 12-18-20, 02:17 PM
  #87  
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Come to think of it, the essential difference between the rear and front shifting is that the derailleur operates on the untensioned side of the chain in the first case and on that normally tensioned in the second. Everything else just follows from that. Incidentally, the shifting in the rear together with the front, or a bump on which the front shifting is done, both temporarily help relieve the tension in the chain. When going uphill, the tension can be so high that front derailleur cage cannot affect the chain.
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Old 12-19-20, 02:30 AM
  #88  
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Originally Posted by mack_turtle View Post
Am I the only person who is aware of the Nuvinci hub? You folks talk about VCT as if it's never been applied to bicycles.
Problem with the Nuvinci is the energy efficiency is down below 90%, while the derailleurs a are averaging in the high nineties and the internal gear hubs not far behind.
All CVT designs have significant lower efficiencies than gears/derailleur transmissions so they are limited to niche situations such as narrow torque bands, need for smooth speed changes, or wide ratio range and novelty situations.
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Old 12-19-20, 07:51 AM
  #89  
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When I was very young, and had more time for riding - I still welcomed 3x systems for low enough gears.
Some time later, after having assembled my first ever road bicycle, and grew a bit stonger, 53-39 cranks were OK for all the local hills, provided I had a 28 tooth at the rear for when I get very tired.
2 - 3 tooth jumps at the rear? Didn't bother me when I was at full strength. Now - any excuse is good, I suppose.

Nowadays - 53-42 cranks are a bit too hard, even with a 34 T largest sprocket at the rear - at least for the climbs that are both steep and long.
But, as far as I'm concerned, this problem is solved with the good old triple - not by having my wheel crazily dished, to accommodate for 12!? sprockets.
Still happy with 6 and/or 7 at the rear, and went back to friction shifters because they just always work - even if cables get frozen solid, takes just a small tug.

I like being able to run dirt-cheap chains and cassettes. What I seem to lack is more time for riding, not more gears.
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