Help Needed - Frame Specs for Di2/EPS

[Kyle h]

Also I’m not gonna lie, I just spent a fair amount of time trying to find this bike in IG as I’m pretty curious who it is.

[dan_hudson]

Big finish... The builder followed up with an explanation of why they now put the Di2/EPS port in the bottom bracket. Note, these are steel frames, not carbon as some theorized. FYI, English is not the builder's native language:

I 100% understand what you (and SHIMANO) are explaining, but the real situation is different.

Recent powerful front derailleur will destroy the seat tube when we put braze-on front derailleur mount especially on the thinner tubes like CENTO or most ordinary seat tubes. The tubes will likely to get cracked within 5 years. Also drilling the Di2 hole on the tube will make a similar situation.

So not only for your frame, but also the most frame we build has the Di2 hole behind the bottom braket to avoid the frame damage. (Or If customer really wants the front derailleur mount and Di2 hole on the seat tube, we use very thick customized seat tube, but it will make the frame stiffer. Also for your frame, using CENTO tubes is the priority).

So I hope you would understand that we think this is the best solution for both performance and durability.

So it seems the error here is one of communication. I thanked the builder for explaining their reason and took the opportunity to strongly suggest they disclose this upfront in the future so as not to surprise another customer + to give them the option for the thicker seat tube + traditional location.

Me? Not sure yet. Pretty sure I will not build with Di2 as originally planned. Might build it up instead with eTap. Or might sell it.

[dan_hudson]

Also, the frame in question is a Cherubim Cento. If you look at their Instagram, you'll notice 99% of their electric drivetrain builds are eTap, perhaps reflecting their opinion that the FD wiring port is not compatible with this tube set. But it wasn't mentioned/discussed when I made my order.

Like a couple other recent Cherubim buyers, my vision was a mostly Japanese build, thus Di2.

Before the knives come out, while I wish this had been disclosed, I give the builder credit for taking the time to explain their reasoning. More respect than I've been shown by other esteemed builders in the past. And Cherubim does have a reason, even if they are marching to their own beat.

[charliedid]

At least you now have an answer.