Nerdy Di2 Battery question

Discuss light weight issues concerning road bikes & parts.
TheRich
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Re: Nerdy Di2 Battery question

Post by TheRich »

Calnago wrote:
Fri Oct 11, 2019 11:44 am
cyclespeed wrote:I think it's clear that the FD uses more than the RD, but how much more...?

Like if there's some flat between 2 uphills, is it better to shift down 3 on the cassette or just move up on the front? These questions keep me awake at night!!
You’d sleep like a baby with a mechanical drive train Image.
I wonder how many times I can plug in my Di2 in the amount of time it takes to change cables.

Butcher
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Re: Nerdy Di2 Battery question

Post by Butcher »

Yeah, it's a nerdy question for certain.

It will never happen if you maintain your bike. A dead battery will happen as often as a broken shift cable on a properly maintained machine.

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Calnago
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Re: Nerdy Di2 Battery question

Post by Calnago »

TheRich wrote:
Calnago wrote:
Fri Oct 11, 2019 11:44 am
cyclespeed wrote:I think it's clear that the FD uses more than the RD, but how much more...?

Like if there's some flat between 2 uphills, is it better to shift down 3 on the cassette or just move up on the front? These questions keep me awake at night!!
You’d sleep like a baby with a mechanical drive train Image.
I wonder how many times I can plug in my Di2 in the amount of time it takes to change cables.
That’s not even a remotely relevant analogy I’m afraid. In fact, there is no analogy in the mechanical drive train world that could be compared to charging a battery. Charging is an extra step that is specific to electric drive trains only. Perhaps a more appropriate analogy to changing cables out might be changing a battery out. You’d likely have to remove the BB, disconnect it from the junction box, within there somewhere, fish a few wires around, reconnect them, etc. I’ve got bikes that have gone for years with the same set of cables. And work perfectly. And if I didn’t touch the bike for twenty years, I could come back to it some day, put some air into the tires and ride off. Imagine fastforwarding some years with a battery that’s been sitting idle for that long. Then try to find a replacement for it.
Anyway, it was just a humorous, yet relevant comment to @Cyclespeed’s equally funny comment about how it keeps him awake at night. I’m sure he really doesn’t lose that much sleep over it. You shouldn’t either.
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spdntrxi
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Re: Nerdy Di2 Battery question

Post by spdntrxi »

hate to break it too you... you want an extra step with mechanical ...cable stretch. Yes same set of cables, but it does happen. If you think charging a battery is such a huge ordeal, you must hate putting gas in your car. :beerchug:

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Calnago
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Nerdy Di2 Battery question

Post by Calnago »

Cable stretch? Hmmm, don’t really notice that with campy cables. Kind of a set it forget it kind of thing. Sram, maybe. But if they do, an eighth of a turn or whatever on the cable adjuster isn’t such a big deal. Think of it like zeroing in an electric system, which actually takes longer than turning an adjuster, especially if you can’t really remember the light sequence and colors etc. and which buttons to hold long and when to press short, etc etc. you know what I mean I’m sure. And I don’t think charging is such a big deal, but yes, it would be great if I didn’t have to put gas in my car. Now that’s a good analogy to charging your bike. That’s part of what makes bicycles so great, their simplicity and lack of dependence on such things. Well, unless you choose to be dependent on it. If all my bikes were electric, I’d want them to be chargeable wirelessly and my entire garage floor to be a charging mat. I’d hate to keep track of which ones were charged and which weren’t.
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spdntrxi
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Re: Nerdy Di2 Battery question

Post by spdntrxi »

garage floor charging mat... I could go for that. Imagine charging your electric vehicle that way... certainly in the future

Butcher
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Re: Nerdy Di2 Battery question

Post by Butcher »

Calnago wrote:
Sun Oct 13, 2019 2:58 am
And if I didn’t touch the bike for twenty years, I could come back to it some day, put some air into the tires and ride off. Imagine fastforwarding some years with a battery that’s been sitting idle for that long. Then try to find a replacement for it.
Not where I live, it would be stolen. :D

The fact is that batteries need to be charged and if you are the type that do not keep up with that, then you are probably the type that does not bring tools/spares with you. Stupidity is something I cannot help with.

There are so many ways to think that an electrical system will fail, but mine has not. The fact is, I have saved more time tinkering with my bike since I changed it to EPS that I can ride more. Well, not really ride more but there is less maintenance than any mechanical set up I've ever had.

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cyclespeed
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Re: Nerdy Di2 Battery question

Post by cyclespeed »

Yes, it was a tongue in cheek question, but I was genuinely curious as to how much more juice the FD uses per shift than the RD. I think it's not as much as people think.....The FD doesn't do that much work, it just has a longer travel than the RD.

And I don't carry a spare tub with me, just a can of repair foam, so no need to carry a 2nd battery either!

The question arose because I moved house recently and all my things are split between 3 places, so couldn't charge as often as I would have liked.

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Dan Gerous
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Re: Nerdy Di2 Battery question

Post by Dan Gerous »

If someone has a lot of time to lose, one could make the test, fully charge the battery and in the stand, shift only the front, up/down/up/down... until battery goes out, count the number of shifts or save it as a ride on your Garmin if you have the wireless module, then do the same for the rear... and see how many of each you get per battery cycle.

Campervan
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Re: Nerdy Di2 Battery question

Post by Campervan »

If it is starting to get low, if you use semi or full synchro, go to manual mode, as the synchro uses more battery.
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