Hi all,

I’m looking at building up a new gravel bike with GRX Di2 but the frame only has external routing and I’m worried about protecting the cable and junction box. Has anyone any experience with this?

Cheers,

Pete

Not considered Sram Force AXS and Eagle?

DI2 is weathertight and shimano has proper guides for external routing. Personally, I’d drill the frame.

@buenfoxa it’s a fair step up in price.

External cabling just looks wrong. I had my carbon frame modded to internal cable routing when I fitted Di2.

If I was going e-shifting now I’d be seriously considering SRAM Force etap. Just bolt on the shifters and mechs and off you go with no phaffing about with cables. If its a gravel bike you could go 1×12 and save a bit of cash on the Force system

As above, external routed di2 looks sht.

External cabling just looks wrong. I had my carbon frame modded to internal cable routing when I fitted Di2.

I barely notice it on my trike. I use the shimano cable cover along the underside of the down tube. Running 1×10. On a yellow-blue frame. Battery behind the seat tube, but the original water bottle mount is fine too.

Looks fine. On black it would be invisible.

External di2 looks terrible

I barely notice it on my trike.

On things that are noticable on that, external cabling is a long way down the list.

I’m in the process of doing this on my MK1 tripster. I’m using a pro tharsis xc stem so I can mount the battery in the steerer tube and the mt800 MTB  junction box because it was cheap and gives wireless connectivity.

The junction box b mounts externally on the bottom bracket and seems pretty well protected.

The tharsis stem is clever. It replaces the star nut with an adjustable nut on the stem too do preload, you then replace the bung/starnut with a battery holder and the cable routes through the stem.

RRP isn’t cheap but I found one for £25.

On things that are noticable on that, external cabling is a long way down the list.

Harsh 😉 . I paid £200 for the entire 10 speed Di2 parts. By contrast, I paid £1100 for the SRAM Red ETAP TT on my other TT bike (also steel frame). There’s no difference in performance whatsoever.

If I’m honest, the black cable tidy doesn’t stick as well as it could, I can hide the junction box in the TT extensions and the it’s 1×10 so no FD cable. I did measure the cables carefully and they come in a lot of lengths. The rear junction box is zip ties inside the rear drive side chain stay.