Shimano R9150 RD - Why so few direct mount hangers?

[msv]

I notice you kept the semi circular ridge on the inside mounting face. Are you using that to deflect the incoming axle from dinging the underside of the dropout when mounting a wheel? Otherwise, it serves to no structural purpose, it only adds to the amount of material removed/machining costs.

Since I'm not trying to optimize this for machining time in order to produce it, the machining time and cost is irrelevant. It doesn't increase the amount of material removal, as the raised circular boss still needs to be there, so the overall starting material thickness would be unchanged even without it. It is there to help protect the frame when mounting the wheel.

[msv]

What's the final weight?

Even the hanger from Most (Pinarello) which doesnt seem to have big lighting effort can reduce some grams...

It's 3g lighter than the Dura-Ace that has a titanium bolt. It could certainly be lighter than it is.

[maxxevv]

What's the final weight?

Even the hanger from Most (Pinarello) which doesnt seem to have big lighting effort can reduce some grams...

It's 3g lighter than the Dura-Ace that has a titanium bolt. It could certainly be lighter than it is.

You could shave a few grams by boring out the center depression. The BMC ones are hollowed out in that area.

[Klaster_1]

You could shave a few grams by boring out the center depression. The BMC ones are hollowed out in that area.

I plan to do exactly that, BMC DM hanger with R9100 has very distinct look. When modelling's done I will be able to estimate savings, but basic idea is that DM should weight approximately the same as regular one, and no B-link would save ~12g.

[Cemicar]

Yeah, hollowing would save more grams (BMC one only adding 3 grams to the standard one), and perhaps you can also paint it...

[Klaster_1]

@msv do you have and B-unit measurements left? I'd like to compare with mine.

[msv]

@msv do you have and B-unit measurements left? I'd like to compare with mine.

Use the attached dimensions, which come from Shimano. Of course you will need to establish the fixing screws in the correct location, which you can do by referencing your original hanger/b-link assembly.

[pdlpsher1]

Today I got an email from Paragon and they are sending me two direct mount hangers, the road version. I've been using the MTB version on my road bike without issues. But Paragon has finally released the road version this week. Here's a comparison between the MTB and Road hangers. The Road is on the bottom. The Road is noticeably longer. When I get mine I'll be able to do a side-by-side comparison in the same photo.

[Calnago]

@pdlpshr1: that’s all well and good but the issue with your setup is not so much the hanger itself but the position of the dropouts. The design of those dropouts is such that they give the frame builder some wide latitude as to just how they get positioned, unlike many dropouts which have to be built around very specific seatstay and chainstay angles. In your case I believe your dropouts are rotated clockwise to an extent that it doesn’t matter which hanger you use, it’s still going to be in an awkward position due to where the hanger mounting bolts are on the dropout. So, the only way you’re going to get the derailleur where it should be with respect to Shimano’s specs is to have a custom hanger made for your frame taking into account the position of the mounting screws and other frame parameters as it has been built. At least that’s my take but will be interested to see where this one positions your derailleur as it is first. Maybe it will end up close enough. I know you think it’s just fine but currently it’s a long ways from where it could and should be for optimal performance as Shimano designed it to provide.

[pdlpsher1]

Yeah Calnago I understand your point. If you go to Carl Strong's website all of the pics show the hanger in the correct position, whereas mine is rotated. Perhaps Carl has a reason for this. I really don't know and don't care frankly. The shifting (Di2) is lightning fast and I have aboslutely no issues whatsoever. If I really did have issues I will pursue a solution since I'm a perfectionist. When I get the replacement hanger I will install it and re-adjust the B screw, and call it a day. I'm posting an update here to help others who might be interested in getting a DM hanger.

[Calnago]

If you were a perfectionist...you’d want the derailleur to be where it’s supposed to be according to the Shimano specs.
You do know that regardless of whether a direct mount hanger or a regular hanger is in use, the ultimate position of the derailleur in space should be exactly the same, right? We went over that way back in this thread. Anyway, looking forward to seeing how it sets up when you get it.

[nycebo]

True words Calnago. But damn is that adapter isn't ugly as sin. Makes the rear mech look way too spindly. Much prefer the one piece direct mount. Anyway it is ultimately irrelevant because the one piece hangars will be prolific in due time.

[Calnago]

That is a “one piece” hanger, it’s not like an extra link that the new Shimano derailleurs use (b-link) to enable mounting on a regular hanger. Or the same piece in the new Campy 12sp. It replaces the entire hanger that is on the bike now. The potential issue is due to the orientation of the dropout itself, which rotated the mounting holes for the hanger clockwise a bit too far in my opinion. But we’ll see.

[Klaster_1]

Still has to be delivered, anodized and tested.

[Klaster_1]

Still need to anodize and check for shifting regressions.