Still continuing on with the Scott Foil Di2 thread, I thought that it may be of interest to some in the conversion I recently carried out on my Scott Foil 20 carbon bike from mechanical to a part internally routed Ultegra Di2 system. It must be noted that this system is different from the older generation Dura Ace 7970 which has different cable/connector sizes and also does not have E Tube compatibility so cannot therefore be diagnosed with Shimano software.
A few cautionary words before I continue. It must be understood that the procedure I have carried out has been carried out at my own risk, as the safety of the frame has now been ‘theoretically’ compromised and is NOT recommended by myself and certainly not Scott, as it will also invalidate your frame Warranty. In my particular case, I am the second owner and therefore no Warranty exists anyway, so nothing lost there.
I took a long time to pluck up the courage to carry out the work after reading volumes of advice and conflicting comments from numerous people, companies, forums, blogs, etc, etc, on the subject of drilling into a carbon framed bike. I have read of quite a few successful stories of carbon bikes being drilled for internal cable routing, but none to date, ever, of anyone suffering from frame failure after just one small hole had been very carefully drilled into a carbon frame at a strategically placed point, unless someone else comes up with something I am unaware of.
It seemed especially interesting that the next level up Scott Foil Di2 specific frame has a hole drilled for the battery cable to which I have copied exactly and does not appear to have any additional reinforcement in the carbon weave.
That all said, it is at my risk and I stand by the actions I have done, although I know as night follows day I will get the backlash from some. But here goes anyway!!!....................Figure 1:
First on the menu was to change both shifters from mechanical. Note the loop in the cable. This was to ensure that the connector remains in its place if the cable is pulled inadvertently.Figure 2:
A shot of the 2 cables fitted and taped. In my case, the best position for the EW67A junction was to hang from the handlebar from a tie wrap and not tied to any brake cables.Figure 3:
The 3mm hole for the previous front derailleur steel cable had to be opened up marginally with a file to 6mm to accept passage of the Di2 cable connector from the new derailleur to the Junction SM-JC40. For info, the cable is only 2.5mm dia but the connector is approx 6mm.Figure 4:
A 6mm x 3mm rubber grommet (RS Part No.6663593), was split with a Stanley knife and inserted around the Di2 cable into the frame hole protecting the cable from chaffing and also providing weatherproofing to the frame interior. A small dab of silicone grease eased the entry as it was a bit fiddly!Figure 5:
A 6mm hole was drilled to accept passage of the Di2 cable from the external battery to the Junction SM-JC40. Masking tape was used to mark the hole and I used progressively bigger drill sizes starting at 1mm up to 3mm and then a round file to take it up to 6mm so as not to cause any potential stress cracks to the carbon fibre. This hole is in the same position as that of the current Di2 specific Scott frames. A Shimano round hole grommet SM-GM01 was slid on after the cable was fitted.Figure 6:
The next job to tackle was to run the cable from the Junction SM-JC40 to the rear derailleur. I decided not to try and drill the existing hole out at the rear of the chainstay for fear of weakening the carbon in that area but also to retain the flexibility of the frame so it could still be used for mechanical cables should it ever be required. If the hole was drilled out, there will be no stops for the outer cable to rest on for tension. Instead I drilled a 6mm hole at the front end of the existing cable guide below the bottom bracket and was able to lay the cable nicely in the guide slot that was there already. I used a small dab of silicon to hold the bracket in place.Figure 7:
The rear derailleur cable enters into the bottom bracket area and will be routed above the bearing when it is fitted into the shell and connects with the Junction SM-JC40. Figure 8:
The cable is run underneath the driveside chainstay to the rear derailleur within a Shimano cover sheath SM-EWC2 and is almost invisible to the eye with the bike assembled.Figure 9:
The rear derailleur now connected. Ensure sufficient loop in the cable to allow for the derailleur to swing.Figure 10:
I fed the cable from the front lever Junction SMEW67A (in my case) to the Junction SM-JC40, through the existing rear gear cable hole in the top tube. I carefully split the plastic grommet with a junior hacksaw fitted it around the cable and used ordinary insulating tape to tape it together again, which also tightly secured it within the hole to avoid dropping out under vibration.Figure 11:
The cable was secured to the frame with a cut down Shimano cover sheath to avoid flapping in the wind.Figure 12:
All the cables now run through the frame and connected up to the Junction SM-JC40 and ready for inserting into the downtube. Prior to fitting the bottom bracket, it was time to see if the system actually worked and there were no loose connections anywhere. I found the Shimano cable tool TL-EW02 invaluable and would recommend this to anyone for the few pence it costs. Yes you can get away without using it but why risk damaging the connector for a few pence?Figure 13:
In my particular case I was mixing older 6770 levers with the newer 6870 front and rear derailleurs and with the battery fully charged up, to my horror found there was nothing happening to either derailleur when the levers were operated. I rigged the system up to the Shimano E Tube SM-PCE1 diagnostic interface device and downloaded the latest firmware, followed by diagnostic checks of all equipment. In a short time all was up and operating successfully. The above pic is a screenshot of the system after it had uploaded the new firmware and run through diagnostic checks successfully.Figure 14:
At last, the finished article! A word of warning though to all Scott Foil owners – when refitting the bottom bracket, make sure that you use an epoxy glue to secure the push fit PF30 bearing in place. This will stop any movement of the bearing within the carbon frame shell, which if not treated, will at best cause creaking and at worst, create wear in the frame and render it useless if left too long.