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Shimano Di2 XTR 3X with Mechanical Disc Brakes

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Shimano Di2 XTR 3X with Mechanical Disc Brakes

Old 09-22-15, 01:56 PM
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Gtmather313
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Shimano Di2 XTR 3X with Mechanical Disc Brakes

Wanting to upgrade my C'dale tandem to electronic shifting. Want to use Shimano Road Brifters (Brake/Shifters) and need to keep front 3X shifting and can do 10 or 11 speed rear cassette. Want to keep mechanical disc brakes but might consider hydraulic.
Please respond if you have first hand knowledge of this set up.
Thanks!
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Old 09-22-15, 04:53 PM
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No first hand knowledge, but apparently Santana has experimented with 11spd road brifters for Di2 and XTR Di2 FD/RD and finds that the FD will swing a triple. Since XTR assumes a bit smaller CW than road, my informant says it works with upto 50-52t CW, and of course honking big rear cassettes upto 36t or so. This is not Shimano's intended use, just a discovery by trial and error by Santana, and my understanding is this will be offered shortly by Santana on their tandems.
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Old 09-22-15, 05:35 PM
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Thanks for the info on Santana's set up! I'm using FSA SL-K crank (52/39/30) so it sounds like this set up may work. Do you know if the Shimano Di2 brifters Santana is using are mechanical brakes? Sounds promising! Hope to hear from others.

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Old 09-22-15, 06:04 PM
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you can get either kind of shifters in the road version and it doesn't matter if they are 10 or 11 speed as they are just switches as far as the derailleurs are concerned. I have used both the mechanical and hydraulic versions and they both work just fine. You can get the same range with a double easily now with the large rear cassettes as we are now using an 11-40 for mountain riding with a 50/34 double The wolf components road link makes it easy with Ultegra or Dura ace..
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Old 09-23-15, 08:10 AM
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Do you know if I need to do any special programming to use the Dura Ace Brifters with the 3X XTR Di2 FD? Lennard Zinn wrote about a year ago that the road brifters didn't accept/respond to a 3 clicks/shifts. Anyone have any more insight to this set up? Thanks!
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Old 09-23-15, 01:33 PM
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Originally Posted by Gtmather313 View Post
Do you know if I need to do any special programming to use the Dura Ace Brifters with the 3X XTR Di2 FD? Lennard Zinn wrote about a year ago that the road brifters didn't accept/respond to a 3 clicks/shifts. Anyone have any more insight to this set up? Thanks!
AFAIK, none of the shifters (road or mtn) maintain a derailleur shift state and simply send up or down "click" messages to either derailleur.

Can you provide a link to that Zinn post?
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Old 09-23-15, 01:39 PM
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Here's Lennard's comment "But you can forget about having “a true electronic 311 (or 10),” because there is no road Di2 lever with three clicks. So you would have to go to a 2X system. And skip to the next question below for details about making it 2 X 11 or 2 X 10.

And the link to his column: Technical FAQ: Di2 XTR opens up gear options for road bikes - VeloNews.com



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Old 09-23-15, 01:58 PM
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My guess with 3+ years experience with road Di2 you have to at least make sure all firmware is up to date for each component. I recently put the XTR display into my road system and it would not recognize it until I did a firmware update on all the components. Same with hydro shifters from mechanical. BTW the etub e software no longer the has auto update feature as I had to download and reinstall the latest version.
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Old 09-23-15, 04:56 PM
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Originally Posted by Gtmather313 View Post
Here's Lennard's comment "But you can forget about having “a true electronic 311 (or 10),” because there is no road Di2 lever with three clicks. So you would have to go to a 2X system. And skip to the next question below for details about making it 2 X 11 or 2 X 10.

And the link to his column: Technical FAQ: Di2 XTR opens up gear options for road bikes - VeloNews.com



ok, I read the entire post. I'm a bit uncertain of that statement
you can forget about having “a true electronic 311 (or 10),” because there is no road Di2 lever with three clicks. So you would have to go to a 2X system.
because:
1) no Di2 road shifter has 2 clicks as a 2x1(n) setup only needs 1-click to shift the FD in either direction. Then why would a triple ring setup need "3-clicks"? One would surmise a triple ring should need just 2 taps.
2) I believe that at the time of his post in 2014, Lennard had not actually tested the Di2 road shifters with XTR Di2 derailleurs, and to my knowledge (fwiw) he has yet to do so or at least post those results.
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Old 09-23-15, 06:29 PM
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That was wrong read his next post on Jun. 10 2014.

Technical FAQ: Biopace chainrings and other gearing questions - VeloNews.com
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Old 09-23-15, 06:46 PM
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Good find! Glad to see Lennard clarify his compatibility comment. It looks like the Dura Ace brifters will work with the XTR Di2 Deraillers but the unknown seems to be if the 3X Di2 FD will work with the 52 teeth big chainring.
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Old 09-24-15, 12:01 AM
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I recently setup a bike with the inverse at the shop where I work: Road Di2 derailleurs with MTB Di2 shifters on a flat bar road bike build. Once I'd used Shimano's software to do all of the updates, then everything played nicely together.

I agree that chainring size should be the only issue, and on some bikes the fact that there is no XTR Di2 FD that will fit to a road braze-on mount will also be an issue, but if you can use a clamp-on FD then it's not a problem.
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Old 09-26-15, 08:47 AM
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Shimano Di2 XTR 3X with Mechanical Disc Brakes

One question is whether you really need to stay with a triple.

With 11 speed cassettes you can cover a wide range with reasonable spacing.

We're running durace di2 with the k edge conversion with 52/36 upfront and 11-36 cassette. Shifts beautifully and gives 1 to 1 gearing. Could go to 50/34 11-40 if needed.
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Old 09-26-15, 11:07 AM
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Originally Posted by merlinextraligh View Post
One question is whether you really need to stay with a triple.

With 11 speed cassettes you can cover a wide range with reasonable spacing.

We're running durace di2 with the k edge conversion with 52/36 upfront and 11-36 cassette. Shifts beautifully and gives 1 to 1 gearing. Could go to 50/34 11-40 if needed.
It is interesting to hear more and more people say that the 11 sp cassettes have reasonable spacing. Coming from a mountain bike background, I have never really noticed the larger jumps in the cassette. I have certainly never owned a super tight "corn cob" cassette that has very small jumps.

With all the wide range cassettes coming out and 11 sp, I am beginning to wonder if the triple will become a thing of the past? Or maybe just relegated to low end components?

It will be interesting to watch it all play out.
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Old 09-26-15, 11:24 AM
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Originally Posted by colotandem View Post
It is interesting to hear more and more people say that the 11 sp cassettes have reasonable spacing. Coming from a mountain bike background, I have never really noticed the larger jumps in the cassette. I have certainly never owned a super tight "corn cob" cassette that has very small jumps.

With all the wide range cassettes coming out and 11 sp, I am beginning to wonder if the triple will become a thing of the past? Or maybe just relegated to low end components?

It will be interesting to watch it all play out.
I believe triples will become a very small niche item. Manufacturing economies play a big part. As an analogy look at bike sizing. I would think due to a larger population, some individuals getting taller, and more women riding there is a wider range of body sizes riding and buying bikes now than in the past. In spite of this manufactures have reduced sizes available because it is cheaper to make 4 sizes than 14. Fewer sizes or options lowers manufacturing and inventory costs. The women's world time trial champ just won on a completely black Trek frame because her sponsor did not offer a bike small enough.


Opinion: The importance of respecting sponsors | Cyclingnews.com

Triples will go the way of well fitting frame sizes and shoes.
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Old 09-28-15, 08:42 AM
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We use Di2 (2x11) and don't miss a triple because the gearing is low enough. I don't think that ratio spacing should be a concern unless the team likes to stick within a narrow cadence.

Through my training with a local ride group, I've learned that it's possible and desirable to vary cadence from 60 to 120 rpm. We use low cadence and high effort (eg. 60 rpm @ 100% threshold) to build strength, and short bursts of 110-120 to build leg speed. Although we prefer to ride at 85-90 rpm, we can vary our cadence to deal with terrain changes or to stay in a paceline.

During a recent tandem rally, we were surprised to see some teams riding at a really low cadence, or have trouble varying cadence for terrain changes.

if you're willing to splurge on Di2, it's easier to learn to ride at slightly difference cadence rather than stick with a triple (heavier and less reliable shifting).
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Old 10-02-15, 09:29 AM
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Great comments on how double and triple cranks relate to gear range, gear spacing and cadence. From a pure athletic performance standpoint one cannot simply learn to turn a lower cadence and get higher watts over a long time period. In fact the goal is exactly the opposite....learn to turn a higher cadence while maintaining the same pedal force. In Bradley Wiggin's recent book he talked extensively about how in order to win the Olympic TT he studied his competitors' watts and AT and concluded that he had to "learn" to put out the same watts at 8 RPMs higher cadence. This wasn't easy as it took him six months of specific power/cadence training.

So I know the trend of 1x and 2x cranks has mechanical advantages of simplicity, reliability and weight saving, (and I have bikes with 1x, 2x and 3x drive trains) but if the main goal is maximizing speed over a long distance with elevation changes then cycling exercise physiologists will prioritize gear range and gear spacing....at the expense of mechanical weight and reliability every time.

That said, let me know if you have any first had experience or knowledge of using Dura Ace Di2 Brifters with XTR Di2 FD and RDs.... Cheers!

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Old 10-04-15, 08:06 AM
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Originally Posted by Gtmather313 View Post
if the main goal is maximizing speed over a long distance with elevation changes then cycling exercise physiologists will prioritize gear range and gear spacing....at the expense of mechanical weight and reliability every time.
I can understand why some team hope for a Di2 triple because they prefer a close-ration cassette, or they don't want to swap out their triple crankset and 10sp wheelsets.

It's harder for me to understand why physiologists would recommend a triple crankset (eg. 53-39-30) with close-ratio cassette (eg 23T or 25T) over a double crankset (53-29 or 50-34) with a 25T or 28T cassette for speed. I'm not aware of any racer (incl Wiggins) using a triple Di2 setup for the mountain stages in the Tour De France. However, I've heard of racers using a 50-34 with a 28T cassette for really tough mountain stages. [FONT=arial]

As an average recreational rider, I've done my share of century rides or Gran Fondo (100 miles+ with elevation gain of 6,000+). I can't recall anyone in these events using a triple crankset (mechanical or electronic), especially among the fast, ranked riders who can finish these events in about 3.5 hours.

As for the XTR Di2, all the reviews that I've read have used the 2X drivetrain configuration. It will be rare to encounter a XTR Di2 with triple rings because the double or single crankset work so well for the vast majority of recreational riders and racers.

We're really happy with 11sp Di2 on our tandem after using it for two seasons. We don't miss our triple crankset even though we do extended climbs of 6 to 8%.
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Old 10-29-15, 09:35 PM
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Originally Posted by akexpress View Post
you can get either kind of shifters in the road version and it doesn't matter if they are 10 or 11 speed as they are just switches as far as the derailleurs are concerned. I have used both the mechanical and hydraulic versions and they both work just fine. You can get the same range with a double easily now with the large rear cassettes as we are now using an 11-40 for mountain riding with a 50/34 double The wolf components road link makes it easy with Ultegra or Dura ace..
Have you had any luck with the Wolf Roadlink? I added it to my di2 Dura Ace and it would not shift up from the 11 or 12 cog. It did ok on the larger cogs. I've been looking for a more cost effective alternative to the K-edge conversion.
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Old 10-29-15, 10:04 PM
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The difference one sees in the pro ranks is that they can turn small cassettes which of course already have very close ratios. Those of us who might want an 11-40 cassette are in a whole 'nother world. I'm inclined to credit the Wiggens' experience. We have a 10 rpm gap between our rear cogs on a 12-34 cassette. Like mtseymour, we prefer to ride with a cadence between 85 and 90. Over a 10 or so hour day, riding at slightly unfavorable cadences does wear on one. I would not look forward to larger gaps.
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Old 10-30-15, 01:53 AM
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Originally Posted by DKMcK View Post
Have you had any luck with the Wolf Roadlink? I added it to my di2 Dura Ace and it would not shift up from the 11 or 12 cog. It did ok on the larger cogs. I've been looking for a more cost effective alternative to the K-edge conversion.
The Wolf Roadlink is working great on our tandem with an Ultegra Di2 11-speed rear derailleur (long cage) and XT 11-40 cassette. I was worried about the distance between the guide pulley and the smaller cogs, but in practice it hasn't had any troubles and has always made the shifts. I didn't do anything special, so I don't know what to suggest for you to try. Maybe the difference between our long cage Ultegra RD and your short cage Dura Ace is important, but I wouldn't expect that to affect the 11-12 tooth shift. Our 11-40 cassette actually has 11-13 as the first two cogs, so they may be shaped quite differently, which may also help.
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Old 10-31-15, 04:15 PM
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Originally Posted by Chris_W View Post
The Wolf Roadlink is working great on our tandem with an Ultegra Di2 11-speed rear derailleur (long cage) and XT 11-40 cassette. I was worried about the distance between the guide pulley and the smaller cogs, but in practice it hasn't had any troubles and has always made the shifts. I didn't do anything special, so I don't know what to suggest for you to try. Maybe the difference between our long cage Ultegra RD and your short cage Dura Ace is important, but I wouldn't expect that to affect the 11-12 tooth shift. Our 11-40 cassette actually has 11-13 as the first two cogs, so they may be shaped quite differently, which may also help.
Interesting you can run a 11-40 with double rings cause the Roadlink is only rated ("supported") with a single ring if using 11-40 per this article. AKA RoadLink ? Lindarets

I like the idea that this adapter simply drops the RD down which provides needed clearances for larger cogs, rather than moving the top jockey wheel rearward like the expensive K-edge solution which also voids the Shimano warranty. Having experimented with maxing out a reversed B-screw (moving the top jockey rearward) I found that setup reduced chainwrap to the point where it skipped under load on a 10spd 34 tooth cog. I can't see this issue occurring with this Roadlink adapter, but possibly less precise shifting on the smallest cogs especially if using a slightly worn chain.
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Old 11-16-15, 09:27 PM
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Indeed it works. I just completed a gravel tandem project with XTR Di2 RD on 10x42 11 spd SRAM cassette, works well. Yes, the 10x44 high gear works well for us, and the intended ultra-distance bike packing, back country races will take advantage of the low 22x42. Crazy.
XTR Di2 FD on 22, 34, 44 chain rings, shifts fine but oh so close to not working. I think the the FD is intended for a mountain style 74mm bottom bracket. On a road bike bottom bracket 68mm wide the FD is set at its very inner most limit both with mechanical and programmed limits. Also only just clears the inside face of the tight Lightning crank Q factor without striking the FD cage. The wide range of rings serves our need, and one might agree with santana that my 22 tooth range in the chain rings could be duplicated in a 30-52 tooth rings. The chain wrap far exceed the rear derailleur spec'd capacity, but with the sychro-shifting and a bit of adjusting the program to shift out of the large ring early, you are prevented from sever cross chaining.
Road bike shift brake levers are Ultegra 6770 coupled with a the XTR display.
I'll post more about the build of this bike in a new "gravel tandem project" posting.
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Old 11-17-15, 02:19 PM
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Turbotandem: It would be interesting to know what the limits are for the XTR Di2 front derailleur. Could you measure the chainline of your small and large rings? Obviously, knowing the small ring chainline would be most important for knowing how easy it might be to get the XTR Di2 FD to work with road cranks, and which combinations are most likely to work best. Thanks.
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Old 11-17-15, 03:03 PM
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Originally Posted by Chris_W View Post
Turbotandem: It would be interesting to know what the limits are for the XTR Di2 front derailleur. Could you measure the chainline of your small and large rings? Obviously, knowing the small ring chainline would be most important for knowing how easy it might be to get the XTR Di2 FD to work with road cranks, and which combinations are most likely to work best. Thanks.
Below are pictures of the chain line in the highest and lowest "cross chain" conditions. One from above and side view of each condition. The last picture shows the 1mm clearance between the FD cage in the high position to the inside face of the crank arm. Tight. The range again is 22-34-44 rings and 10-42 cogs. Interesting results, and found the RD senses the chain tension drop when it can no longer take up the chain wrap and it refuses to shift into any smaller cogs. Smart! The chain does not bottom out on the lower bridge of the FD in the low shin ring until after the 7th cog, and at that point the chain wrap exceeds the RD. What is it that you would like dimensioned?

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Last edited by Turbotandem; 11-18-15 at 09:22 AM.
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