Help with GT Grade Di2 1x11 build

[2oldnslow]

I currently own a GT Grade Carbon Ultegra which I've ever so slightly "weight weenied" with a pair of Reynlods ATR wheels a KCNC seat post, lighter saddle, my favourite 3T carbon bars and a few other "bits" I have to say it's very much become my "go to bike" for all sorts of riding.

I've now decided I want to go 1x11 on it and in the first instance I plan to use a Wolf Tooth 42T chain-ring, a short Ultegra rear mech mounted on a Wolf Tooth Road-link and a (probably XTR) 11-40 T cassette.

Not sure if that will get me any weight reduction but right now that's not the main aim so forgive me posting this is a weight weenie forum.

Anyway at some point I'd like to give Di2 a go and to that end I've got a set of TRP Hylex brakes sitting waiting and which can be fitted with the Shimano R600 climber switches. The Grade isn't Di2 "compatible" but for a 1x11 set up I don't see that as a problem as all "cables" run down the underside of the down tube with the tube to the RD running under the chain stay

I presume apart from the appropriate length E-Tubes I'd also need to buy a junction box and an external battery. Is that correct and which external battery would you recommend? I also toyed with the idea of using the XTR display as I believe that also serves as a junction box. Budget is flexible as long as I can sneak it past my significant other and luckily to her a bikes a bike

Additionally if anyone has suggestions about a "better approach" I'd be very interested in hearing your views.

Thanks in anticipation

a bit of an aside but does anyone know which "variety" of front 15mm thru axle QR the Grade uses as far as I can tell the most common are Fox or Rockshox but I haven't been able to find out which and I'd quite like to get hold of a KCNC 15mm QR

[aaric]

The ultegra derailleur might have issues with the 40t cog even with the link. XTR would be a better plan with its clutch though, with a single front ring - depends on how much your are going to be tossing the bike around. Although, there will probably be an XT Di2 rear sometime next year if you have issues.

If you are doing an external build, consider the new xtr torpedo battery case for the internal battery - it includes a 6 port junction, so you wouldn't need to stick one under the bottom bracket...

If you are budget constrained, the old external battery and holder can be had really cheaply. The xtr junction is pretty nice - gets you battery level for not that much more cost than a standard a junction, and you don't have the hacky rubber band around the stem.

The shimano wire covers are actually pretty good. Not all that noticeable on a black bike if you take your time to run them. The bottom bracket area gets a bit ugly, just because you have so many wires running around - a 1x setup might be a bit cleaner though.

[2oldnslow]

Hi there and thanks for that. The "torpedo" battery mount is a great call and looks a lot sleeker than the alternatives. If I do have to go external for the battery I will definitely be going with that.

I'd much prefer an internal battery solution but right now can't think of how it might be achieved.

I'm pretty sure the short arm mech will be fine with the road link as what off road riding I do do will be on fire roads and "bridleways" here in the UK (think off road touring/bike packing so not that much tossing the bike around) and the chain-ring will be of the narrow wide variety so I'm hoping the lack of a clutch isn't a major issue.

Thanks again

[aaric]

You might check out http://www.bikerumor.com/2014/06/14/fir ... road-bike/ Has a di2 setup installed externally.

You could run the battery internal, but would require a hole into the frame to run a wire. Might be able to pop off a grommit around the bottom bracket. You can usually pull the bottom bracket out and get some access to routing the wires from inside.

maybe here:

[2oldnslow]

Hi there and thanks again this is great stuff.

Re: the battery I have half an idea that the bolt that secures the FD mount to the down tube might (once it's removed) provide access to a seat tube mounted battery. Am I right in thinking I only need access for a single wire if I use an under the bottom bracket mounted junction B ?

[aaric]

Yeah - you just need to run a wire inside to the battery, assuming you use an external junction to hook up the rest.

[2oldnslow]

Many thanks much appreciated

[2oldnslow]

well for the time being I've moved to a half way house 1x11 set-up with an 11-40T 11 speed cassette and a normal length Shimano 6800RD on a Wolftooth roadlink and a KMC X11SL chain it shifts perfectly with all gears useable. Now as soon as the gales in the UK abate I'll give it a road test. "Dinner plate" cassette looks a bit incongruous but now with the Reynolds ATR wheels and the speedplay pedals from my roadbike plus a few other "nice bits" it's sub 8Kg so very very happy.

Will probably go Di2 in the spring with a short Ultegra RD.

[mtbstuff]

So...how's this set up working for you?

well for the time being I've moved to a half way house 1x11 set-up with an 11-40T 11 speed cassette and a normal length Shimano 6800RD on a Wolftooth roadlink and a KMC X11SL chain it shifts perfectly with all gears useable. Now as soon as the gales in the UK abate I'll give it a road test. "Dinner plate" cassette looks a bit incongruous but now with the Reynolds ATR wheels and the speedplay pedals from my roadbike plus a few other "nice bits" it's sub 8Kg so very very happy.

Will probably go Di2 in the spring with a short Ultegra RD.

[2oldnslow]

Hi there mtbstuff

I'm liking it a lot. Most of my riding is done on my own which I think takes away one possible argument to going "one by" in as much as the larger steps in the gearing isn't as crucial as would be the case if i was riding in a group and had to match my speed/cadence to others.

With the XTR cassette I've got all the gears I could possibly need here in the North West of the UK the gear change is as slick as I'd hoped and the chain-line with the quite long chain stays of the Grade doesn't appear to be a problem at either end of the cassette so all in all very very pleased with the set up.

[CBJ]

Any pictures of your setup? I run a Grade too.

[Birdman]

If you are having derailleur range issue, consider RoadLink.

http://www.wolftoothcomponents.com/products/roadlink