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Discussion Starter · #1 ·
I just built up a frame with Ultegra Di2 6870, and I have what seem like really stupid questions.

Am I supposed to soft-pedal or ease up a bit when I'm shifting, like I normally would with a mechanical drivetrain? If I'm cranking hard and I shift from the small ring to the big ring, it feels harsh or sloppy.

The rear seems to shift better if I ease up as well.
 

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I do it out of habit, and there is little doubt that the less hard you are pedaling, the easier the shift, unless you are going really slow. It does seem more smooth to me than conventional shifting, all else equal. Recently I learned just how horrible a worn chainring feels with a new chain.
 

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Discussion Starter · #4 ·
I downloaded the Dealer's Manual for the install, and I've looked at the User's Manuals (which don't seem to have much info other than "only a trained mechanic should install these parts") but what I really want is a sort of Instruction Book. As in, "here's how to use Di2." Does that exist?
 

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You'll find that the position of your cranks makes all of the difference. I always shift under load but initiate the shift with the left crank on the downstroke. It took a while to figure this out.

I don't know if this position is universal but start with that and move the initiation point until you find the sweet spot
 

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I downloaded the Dealer's Manual for the install, and I've looked at the User's Manuals (which don't seem to have much info other than "only a trained mechanic should install these parts") but what I really want is a sort of Instruction Book. As in, "here's how to use Di2." Does that exist?
Then you should get the auomatic version.

Really, push one button for up, the other for down. Ditto on the other side.
You can shift whenever you want. Have you rode with a bike with gears before?

To really get into it, one would need to add telemetry with a recording medium to the bike. If you had power tap, you could set your shift points and possibly setup a 'boulevard' or 'sport' shift points.
 

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Discussion Starter · #8 ·
I'm not looking to change the functionality. I just want to make sure I'm using it correctly and not damaging it.
 

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I ease up on front shifts. I typically shift the rear cogs under power when climbing a hill. I'm seated, and pedaling steady. I avoid shifting at full power, where I'm pulling hard on the handlebar for leverage.

I never noticed that front shifts work better at a certain pedal position. They always seem fast and easy.
 

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Then you should get the auomatic version.

Really, push one button for up, the other for down. Ditto on the other side.
You can shift whenever you want. Have you rode with a bike with gears before?

To really get into it, one would need to add telemetry with a recording medium to the bike. If you had power tap, you could set your shift points and possibly setup a 'boulevard' or 'sport' shift points.
The OP obviously knows how to shift. Why are you posting this?
 

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Discussion Starter · #13 ·
I was ignoring the sarcasm.

Does anyone know if Shimano (or anyone else) has published a video or text-based guide along the lines of "getting the most out of your new Di2 drive train?"

Thank you!
 

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In my experience Di2 is quite happy to shift under load. Obviously that adds some strain on your drivetrain, so you might get slightly less life out of your chain, cassette, and chain rings. So ease up if you want to maximize the life of those items. But the rest of your components don't care if you ease up or shift under load.

I I usually ease up out of habit, but I find myself doing all sorts of things with Di2 that I wouldn't do with mechanical, as it simply never balks and never drops the chain.
 

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You'll find that the position of your cranks makes all of the difference. I always shift under load but initiate the shift with the left crank on the downstroke. It took a while to figure this out.

I don't know if this position is universal but start with that and move the initiation point until you find the sweet spot
I always "soft pedal" when right crank arm is coming up, then shift, laying the chain silently on the ring as I pick up the cadence on the down stroke. Guess it doesn't matter at what point rider eases up for a quarter turn as long as he coordinates that with working the shift lever.

Shifting large to small is always easier. The chain is dropping down to a smaller cog as opposed to crawling up on a larger cog. Don't take no time at all.
 

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I think at first I did the soft pedal thing but after 2 years I have figured out what works. It seems to me it's more capable than I am comfortable with and I downshift some under load but generally have a high cadence going so not clear on stress to drive train. No unusual chain, cassettes or crank ring wear so it takes what I dish out any way. Just ride and you will get a feel for it.
 

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The important thing to remember with Di2 is to not shift if when you aren't pedaling.

As far as shifting under a load, do it like you would choose on mechanical. I do it on both when I feel the need, mostly climbing.
 

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The important thing to remember with Di2 is to not shift if when you aren't pedaling.
This is a great point. The only time I have had a problem with Di2 was descending at high speed in my highest combination and unexpectedly passing some friends climbing (obviously the opposite direction). I shut it down hard, shifted out of the big front and too quickly shifted all the way through the cogs while slow pedaling with no load. It did nothing to the Di2 but it bent the derailleur hanger enough that I could not get the shifting quite right until I replaced it.
 
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