Di2 TT retrofit - where to start?

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OhPinchy
Posts: 80
Joined: Wed Feb 27, 2013 5:38 pm

by OhPinchy

Looking to retrofit Di2 into my Dolan Scala TT bike. It's currently 10-speed Ultegra, looking to go 11-speed Di2 Ultegra. I'm mainly interested in shifting rear derailleur from the aerobars. Seems the TT shifters come only in pairs, so I'll do the front derailleur also if needed. Not essential to do shifters on the bars near the brakes.

There's an almost overwhelming amount of info on Di2 and retrofits out there so I'd appreciate any pointers to a guide to get started on the planning: i.e. list of what I need to order, and steps for installing. I'm in Ireland and don't believe there are professional retrofitting services available locally so it will be a DIY job.

One concern is the Dolan Scala frame has internal cable routing but the holes are really tiny, only accept the width of the gear/brake cable, not the cable housing itself. The bottom bracket area is well built up, I'd be ok with taking a risk and drilling a hole if needed. The seatpost is aero profile, not circular, so not sure how to secure the battery inside the seatpost (definitely want internal battery).

From my initial searches seems like I need:
Front Derailleur: http://www.wiggle.co.uk/shimano-ultegra ... erailleur/
Rear Derailleur: http://www.wiggle.co.uk/shimano-ultegra ... erailleur/
5-port Junction B Box http://www.wiggle.co.uk/shimano-sm-ew90 ... be-5-port/
Cables: not sure how many or what length? http://www.wiggle.co.uk/shimano-dura-ac ... d50-cable/
TT shifters: http://www.wiggle.co.uk/shimano-di2-11- ... -switches/
Junction box for bottom bracket area (guess I need to figure out if it's the internal or external version needed): http://www.wiggle.co.uk/shimano-dura-ac ... -junction/
Seatpost battery internal mount: http://www.wiggle.co.uk/shimano-dura-ac ... nal-mount/

What else am I missing and is there any guide for figuring out what type and size cables I need? Starting to look like quite an expensive setup so I want to price it all up before deciding whether or not to proceed.

by Weenie


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goodboyr
Posts: 1483
Joined: Wed Jan 10, 2007 10:56 pm
Location: Canada

by goodboyr

Best reference blog is http://carltonbale.com/shimano-di2-everything-you-need-to-know/

Start reading and then you can ask more specific question.

2old4this
Posts: 366
Joined: Mon Jan 13, 2014 7:26 am

by 2old4this

goodboyr gave you a real good article, read it throughly...

Once you start, the setup is really easy, except...

If your frame is not di2 compatible you have to figure out how to get the wire from your front Junction A to rear Junction B (and from there to the battery and to the derailleurs.) First take your cranks and bottom bracket out to see if you can pass wires through your frame's bottom bracket area. If there is no access, you'll have to do an external (or partially external) set up.

Make that decision and ask question in this board. There are plenty of us who dealt with the same question switching to di2...

wingguy
Posts: 4318
Joined: Thu Mar 08, 2012 11:43 pm

by wingguy

OhPinchy wrote:I'm in Ireland and don't believe there are professional retrofitting services available locally so it will be a DIY job.


I find it incredibly hard to believe that there are no bike shops in Ireland that have any mechanics :lol:

OhPinchy
Posts: 80
Joined: Wed Feb 27, 2013 5:38 pm

by OhPinchy

Thanks. The Carlton Bale blog was very helpful and gave the info I needed. Particularly like the advice on using pieces of string externally to estimate number and length of wires needed, and advice to add bit extra for buffer.

Took off the bottom bracket to find it's not suitable for routing the cables and Junction B box internally. Am now caught in two minds as to whether it's worth proceeding as I could see it being a lot of hassle to route the cables and would probably have to take a gamble and drill a hole in the frame above the bottom bracket (unless I've understood that incorrectly). For the price of the investment, I'd want a clean and elegant solution but not sure having the cables come out to an external junction box under the bottom bracket would give me that. Rear brake is mounted behind bottom bracket and so may further complicate matters. Point about professional retrofitters was that I thought I'd seen online some US companies that rig up neat battery and custom wiring configurations and may also do the drilling and installation, while there's plenty of good mechanics in Ireland that can do a straight-up install, I'm not aware of any that offer that service.

martfarg39
Posts: 3
Joined: Sun Jan 08, 2017 4:46 am

by martfarg39

could always buy my Shiv TT Di2 (on ebay right now)

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

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goodboyr
Posts: 1483
Joined: Wed Jan 10, 2007 10:56 pm
Location: Canada

by goodboyr

OhPinchy wrote:Thanks. The Carlton Bale blog was very helpful and gave the info I needed. Particularly like the advice on using pieces of string externally to estimate number and length of wires needed, and advice to add bit extra for buffer.

Took off the bottom bracket to find it's not suitable for routing the cables and Junction B box internally. Am now caught in two minds as to whether it's worth proceeding as I could see it being a lot of hassle to route the cables and would probably have to take a gamble and drill a hole in the frame above the bottom bracket (unless I've understood that incorrectly). For the price of the investment, I'd want a clean and elegant solution but not sure having the cables come out to an external junction box under the bottom bracket would give me that. Rear brake is mounted behind bottom bracket and so may further complicate matters. Point about professional retrofitters was that I thought I'd seen online some US companies that rig up neat battery and custom wiring configurations and may also do the drilling and installation, while there's plenty of good mechanics in Ireland that can do a straight-up install, I'm not aware of any that offer that service.


What specifically is the issue with the BB? I understand that this bike is BB86, which means press fit cups. Are you saying that there is an internal shell in the BB area that keeps you from running wiring and JB?

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