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Also, @pdlphsr1... it would be fairly easy to ascertain whether or not your hanger is in the right place or not, and if not, just how far it is out (if it is). The thing is, with your dropout design, it is fairly easy for the frame builder to rotate the dropout (within limits) to accommodate different angles seatstay and chainstay junctions, however... you can't ignore how this is going to affect the ultimate placement of the derailleur. Framebuilders have all kinds of jigs etc to keep things where they want while welding/brazing etc. But it's up to the framebuilder to make sure that the derailleur will end up where it needs to be. If you find out that the derailleur is in fact not where Shimano wants it to be according to their spec, then I'd want to know why the builder departed from that spec. A perfectly valid question for sure.
Oh, and I'm not sure what you mean by the "forgiving nature of Di2". It is anything but forgiving, in fact it is very precise and forceful. You touch a button, and it moves a precise amount, the same way, with the same force, every time. And if you're not ready to shift, like barely pedaling when you hit a hill and hit the button to move to the big ring from the small, it doesn't know anything about the terrain you're about to encounter, or that maybe you are making a bad shifting decision, or that maybe your cadence is a bit slow at the time of shift. It is just going to try and jam that chain onto the big ring regardless, and there's no back tracking once you hit that button until the action is done, or at least attempted. I cringe at the thought of the bad shifts that must occur in the hands of the inexperienced and the mechanical stress it can put on the drive train.
Looking forward to seeing what you find out about your frame and the hanger placement, whether the road hanger makes things right, and getting things adjusted as well as possible.
I must stress that I'm a long time Di2 user and my current setup gives me sublime shifting performance. And I also like the Paragon DM hanger since I can pivot back the RD without much restriction, and others will benefit from the design to help wheel removal.
As for you thinking that being able to pivot the rear derailleur back that far makes for "easier" wheel removal, uh... never mind.
The road DM hanger will also change the position of the RD. At this point I have no issues with the bike so I might just keep everything as is. As I have stated earlier I think the new Shadow RD is awesome, with or without a DM hanger.
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Have you considered grinding the square corner off the b-knuckle to allow the RD to pivot back further?
You can see with the paragon DM hanger that you can pivot the hanger further back compared to the stock b knuckle.
You can see where that square corner on the b knuckle makes contact with the derailler body limiting the movement.
Just an idea.
@Zank... did you grind that off just as an experiment or were you having difficulties with wheel removal as well. The thing is, with the new design, it WILL be a little more of a hassle to remove any wheel, but the benefit of having a really good “wrap” around the cogs outweighs that. With @pdlpsher1’s situation, he doesn’t seem to be getting any of that benefit but I think that may be just how it is given how the frame and its interface with the dropouts turned out.
But good work @zank for demonstrating that. Still, Shimano clearly doesn’t want the derailleur to be able to extend past that stop. I’m not sure exactly why yet, but my guess at this point might be to prevent using the derailleur on super large cassettes that it just isn’t designed for, like a 40 or something. Ha, where will the madness stop.
The “mountainization” of the road bike continues, and I don’t like it.
No, I sacrificed this one because that derailleur is going on a DM hanger and I have a drawer full of mtb and road b-links at this point.
I understand your point about the Paragon hanger being out of spec in regard to not having that positive stop. And I'm wondering if it's there simply to prevent the barrel adjuster from hitting the hanger as in my picture above.
I totally agree the added chain wrap is a plus, just like on the mtb side. We do have a bit of latitude on how we rotate those dropout hoods. I tend to go a little more towards more chain wrap, but I also build few bikes with chainstays under 410 mm and I am hyper aware of my chainstay bridge placement. But the difficulties you are running into make complete sense to me. Tight spaces everywhere these days.
Zanc... you're obviously a frame builder, and apologies if I should know you. I've dabbled in frame building a bit years ago, when carbon was just becoming all the rage. I almost bought my own milling machine. But instead got a Colnago C40. However, I really appreciate the artisan work that can be shown off with a steel frame. Keepin' it real!
The thing with @Pdlpsher1's bike is that he's got long chainstays at 425mm he says. So unless the bridge up front between chainstays is preventing it, I don't see why the dropouts weren't situated such that the end result of the hanger would at least allow the chain wrap that the derailleur was designed to get in the first place. I don't think it's just because of the large 34 tooth cassette, and in any case, the GS cage on the derailleur should allow for that.
And oh yeah... @Pdlpsher keeps going on about how even if your bike does not have a wheel removal issue, that being able to yank the derailleur all the way back like that will make rear wheel removal even easier. I completely disagree with that. Once you clear the upper pulley from the cogs, then pulling the derailleur even further back will not make it easier to get the wheel the rest of the way out. In fact, pulling it back even further is just going to pull on the chain below the lower pulley and just add to the frustration. You want to be able to pull the derailleur back just far enough for the cogs to clear the upper pulley, but beyond that you're just making it more difficult again.
1) First, get a straight edge and place it so that the bottom edge intersects both the center of the bottom bracket and the center of your real axle (the skewer end).
2) Take a little plastic triangle from your kid's geometry set or you can get one at any drug store or school supply store for a couple of bucks and orient them like in the picture below...
Now, line up the plastic triangle thing so that it is a) square to your straight edge and b) intersects both the rear axle center (skewer), and the center of the pivot where your derailleur attaches to your DM hanger... like in the pics below. From that you should be able to read that distance... which in the case below... is ~32mm. And what is the distance according to the Shimano spec again?... surprise surprise... 32.65mm. Imagine that. I'm gonna call this one good. And then the vertical distance below the axle should be 34.39mm. In my pic below that number is slightly more than that after converting the inches scale to metric, but it's kind of a crude setup to begin with while we're just placing that straight edge "about" in the middle of the BB center and the axle. Point is, if we're this close with such a crude measurement, I'm thinking we're probably good overall as far as where the derailleur is in space at least. There's still the difference in hook angle of 10 degrees between the mtn and road hangers, which would only make the road shifting a little more sluggish by setting the derailleur back even a little bit more.
We've kind of taking a few turns and twists in this thread, but let me reiterate the primary reason why I decided to jump in in the first place. It was because I'm getting tired of people who have no clue continuing to say that the DM hanger makes rear wheel removal so much easier. It simply does not. The derailleur's location is, or at least it should be, the same whether you use a DM hanger or a regular hanger with the supplied B-Link. And neither of those hangers are interfering with rear wheel removal but rather, it is the design of the derailleur itself which may, on occasion, make removing the rear wheel a little bit more frustrating. And in the extreme rare cases, a lot more frustrating. Where the wheel gets hung up in those cases is in the cogs and the upper pulley, but if you can get past that, it's all good. The added chain wrap just adds to the crispness of the shift and to the extent it's wrapping more teeth, less wear on your cassette. In a nutshell, it's good. We like it.
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