Di2 Wire warning

philwint

Hope this is the best section.

I've a word of warning for anyone who has Di2 shifting.

I was out today, lost my chain so that it fell between chain ring and frame. It sliced clean through a Di2 wire there rendering my bike a single speed!

Luckily I'd missed the long club run through a timing error, and ended up on a more casual ride with the C group. so was only 25 miles or so from home. Some fiddling with the front limit adjusters gave me the smaller chain ring and i set off back.

Now I'm home and have had a good look it's clear that the wire was routed the wrong side of the chain stay.



Or, at least it would seem more sensible to route the wire the other side to mitigate this risk.

So If you have Di2 can i urge you to have a look behind your chainset and check where that wire goes on your bike. I know it's fairly unlikely that you'll lose the chain (I still don't really understand how I managed it as my low limit adjustment seemed fine), but it can be a right bugger if you do.

I have a replacement wire on order, but a few mins with a soldering iron and electrical tape seem to have got me up and running again for now (I will swap the repaired one out for the new one as I can't guarantee how waterproof I've made it).

I always used to carry a spare gear cable in my bag on my mountain bike. I'm wondering if I should carry a spare Di2 wire on the road bike just to be sure - probably not now I've re-routed the wire.

By the way my bike was built up by Ribble, so i'd be even more careful if yours was too. But I recommend checking whoever built it.

sloppyschleckonds

More reason to get an internally cabled frame

Scrumple

and buy a chain catcher

philwint

Scrumple wrote:

and buy a chain catcher

Good call - I didn't know those existed

Scrumple

I have a K edge on my Wilier - yo can live with the few g it weighs as you know there will never be that grating noise as the chain strips your paint off the crank

A lot of the pros use them, and there have been some arguments here over the need for them. For me, they are peace of mind and do what they are there for! No brainer.

MountainMonster

Surely this has nothing to do with Di2 cables, but more to do with having the cables exterior and also have them wired correctly?

Scrumple

MountainMonster wrote:

Surely this has nothing to do with Di2 cables, but more to do with having the cables exterior and also have them wired correctly?

That's what the OP said! Get the wires the right side of the crank. No one mentioned the cables being at fault!

philwint

Interestingly I've been digging around on the net and found the dealer installation guide from Shimano.

This diagram is exactly how my bike was wired



So the guys from Ribble did it "correctly". But there is clearly a flaw with the "correct" way

(That K edge looks just the job though - I'll certainly be getting one)

arthur_scrimshaw

philwint wrote:

Interestingly I've been digging around on the net and found the dealer installation guide from Shimano.

This diagram is exactly how my bike was wired



So the guys from Ribble did it "correctly". But there is clearly a flaw with the "correct" way

I'd have thought wiring it on the inside of the chainstay would make it far more vulnerable to road debris and (for example) damage from the stone stuck to the tyre? Properly adjusted front mech should prevent chain drop or suck, chain catcher as insurance?

stueys

Seems to make sense not to put the cable where yours was routed just in case. Another vote for a chain catcher, first thing I put on all my bikes (along with the usual elite cages).

rolf_f

philwint wrote:

(That K edge looks just the job though - I'll certainly be getting one)

Try Token - basically the same thing only you get to pay about £8 instead of £26!

philwint

Arthur Scrimshaw wrote:

I'd have thought wiring it on the inside of the chainstay would make it far more vulnerable to road debris and (for example) damage from the stone stuck to the tyre? Properly adjusted front mech should prevent chain drop or suck, chain catcher as insurance?

I did think about that. For the stone stuck in tyre specifically I reckoned as it would have to make it's way past the brake calipers (not much clearance), it was extremely unlikely to be an issue.

For road debris generally the lower junction box and all of the cables are under the BB so I don't think inside the chain stay is any worse.

More searching (good stuff this internet), brought me to the park tools installation guide

http://www.parktool.com/blog/calvins-corner/di2-shimano-electronic-intelligent-system-installation

Which shows the wires going where I have suggested above.

@Rolf - top tip thanks

flasher

I thought the point of Di2 was that you never had to worry about bad shifts ever again.

CiB

Interesting. I routed the cable on mine the other side from how they'd been installed as it looked too close to the ring and could easily snag without much deflection, so have avoided this sort of problem.

I can report that over-enthusiatic cleaning of the chain-stays with a cloth has a similar destructive effect, if that's any help to anyone.

redvee

Rolf F wrote:

philwint wrote:

(That K edge looks just the job though - I'll certainly be getting one)

Try Token - basically the same thing only you get to pay about £8 instead of £26!

Krex on Ebay for £6.50?

http://www.ebay.co.uk/itm/300857806349? ... 1439.l2649

No doubt same as the above but with a different name on it.

bernithebiker

Di2 is crying out for internal frame wiring.

Maybe DIY it? Get the drill out!

rolf_f

redvee wrote:

Krex on Ebay for £6.50?

http://www.ebay.co.uk/itm/300857806349? ... 1439.l2649

No doubt same as the above but with a different name on it.

TBH, I think it is worth £1.50 not to have something written on your bike that looks like it was written by a posh person trying to sound gangsta about splits in the pavement!

philwint

Rolf F wrote:

philwint wrote:

(That K edge looks just the job though - I'll certainly be getting one)

Try Token - basically the same thing only you get to pay about £8 instead of £26!

And i did - and here it is.

Shame it's not quite the same shade of red as my frame lol



But you can see that I still routed the new wire behind the chainstay, out of the danger area, just in case.