oldacura

Just received our new Calfee Tetra outfitted with Shimano Di2 Ultegra. When I bounce the bike on the floor, I notice a rattle that seems to be coming from the captain seat tube area. Based on the sound, my best guess is that it is the electric cables rattling inside the bike frame tubes. I think the cables route down the downtube, through the captain's bottom bracket & then through the boom tube. If this is the case, is there an easy fix?

mwandaw

You might get some good advice directly from Calfee.

andr0id

Those little rubber nubbins you put around MTB cables to keep them from rattling would probably do the trick.

twocicle

I'm totally with you on the noise/rattle sensitivity. I absolutely hate it while riding. The problem is even worse when running full length hydro hoses... lots of donuts, tape, etc needed to eliminate the noise. No solution for excessive stoker feedback yet

The Di2 "buzz killers" for wires run inside tubes are a clip-on strip of plastic that resembles a 3-4" zip tie, but with an open ended plastic clamp. There should be some of these already installed in your downtube (if that is where your noise is coming from), bottom tube, etc.

"Easy fix" depends on one's mechanical abilities and the access points (whether or not your frame has couplers). The length of Di2 wire and location of internal junction boxes can differ depending on your frame type. Your frame may have an internal junction box located near the ECC BB, in which case you would need to pull the front cranks and BB, disconnect the downtube wire and pull it out along with any existing plastic strips (careful not to lose them inside the downtube). Then add more plastic strips, or use zip ties (leaving a 3-4" tail) to do the same effect, and reinstall. For reinstall, using a length of old shift or brake wire, or liner tube, as a routing guide can be a lot easier than trying to run just the Di2 wire with plastic strips attached through the downtube. Similar process with the wire run through the bottom tube.

Did you buy direct from Calfee or a bike shop? If the latter then speak to them, otherwise call Calfee and speak directly with the guy that assembled your tandem, or at least did the Di2 install.

mstyer

Sounds like what you need is the Shimano EW-SD50-I cable ties. They clip onto the e-tube wires that are to be run internally and are intended to act like small leaf springs that hold the wire against one side of the tube.

The other option is not obsessing over what sound your bike makes when it is bounced on the floor and focus on the sounds it makes while riding.

akexpress 

We don't have the noises while riding and the bounce on floor test is not very valid for riding. I don;t have the clip on or zip ties on our wires. My actual bet is it is not the cable but the seat post battery is moving in the seat post. Try removing the seat and unsnap the wire and shake the seat post if you get the same sound just remove the battery and add a couple of layers of electrical tape to the battery to reduce the noise.

oldacura

Thanks for the responses. We bought the bike from a Calfee dealer. I will look into each of the suggestions. Our bike does not have couplers. In order to access the cables, I will likely have to remove the captain BB. Another thought I had was that I could get some foam pipe insulation that has an OD near the ID of the bike tubing. Cut into short sections & push up into the frame tubes to house the cables inside the insulation. Does this make sense? Is this feasible?

Another thought - where the rear der cable comes off of the bars & enters the frame and also where this cable exits the right chain stay and routes to the rear der, the cable is unsupported & looks vulnerable. I zip tied the front end to the brake cable. This seems to route it more cleanly. This can't be just a tandem issue. Is there a more elegant solution?

Thanks.

mtseymour

If the noise is coming from the captain's seatpost, you should remove the eccentric and see if the Shimano cable ties have been installed. They look like this:



It's impractical to push foam insulation into the seat tube or down tube because the BB shell may not provide access. If my memory is correct, the BB shell just has narrow notches to allow the Di2 cable to pass through to the rear BB. The Shimano or regular zip ties work well if they're properly spaced.

radsmd

Stop bouncing the bike.

It may not happen while you are riding it. Give it a try first.

twocicle

No. The access holes inside the BB shell are far too small to fit anything bulky through and into the frame tubing. Likely Calfee put an internal Di2 junction box close to that front BB shell and it may be bouncing around inside.

Usually they install the seatpost battering in the stoker's seat tube along with another junction box therein, so these bits should not be a cause to your rattle noise coming from the front end.


First off, yes I agree that Shimano left these thin wires a bit vulnerable. I don't like using zip ties to hold the wires, because zip ties have no give and could break the Di2 wire.

For the front wire, make use of the rear brake cable as a guide/support lead up to the Di2 junction box on the stem. Either use tape, or spiral wire wrap to cover the wire for most of that run. For the rear exit point, add support by taping the wire to the underside of the chainstay close to the dropout... and/or you can also use the wire wrap to cover the RD wire too.



Our Di2 tandem with the coil wire wrap on the front:


Aside: I put the XTR Di2 display/junction on the left side of the stem as that location works best for when I add 3T "clip-on" TT bars (w/Di2 shifters too). This way, the display can sit in front of the 3T clip-on faceplate. It also plays nicer with the Garmin bar mount which is right side as well. If the Di2 display is located on the right side (per norm) then it would get shifted way too far to the right with TT cliip-ons.

oldacura

Any recommended source for the spiral wrap?

Also - just getting familiar w/Di2: I've watched youtube videos on adjusting techniques. The reason we got it was that everyone here who has it loves it. We went for the widest range recommended: 52t x 34t in front and 11t x 36t in the rear. Though we won't often ride the small/small combo, it looks like the front derailleur cage will rub on the outboard face of the chain in this combo. Can this be trimmed out or is trimming an auto function controlled by Di2? We're coming from a 1998 Co-Pilot with bar end shifters. I could trim out almost any rub. I hate drivetrain noise.

The way I tended to adjust a standard mechanical rear derailleur was to shift into a mid gear, crank the pedals, turn the adjuster nut & count the number of clicks from moving up a gear to moving down. This was usually about 20 clicks. I then divide by 2 (10 clicks) & back it off this far - reasoning that this should center the cage with the cog. With Di2 does anyone know how many "clicks" there are in a full shift step? Is it the same front & rear? Also, it appears that the front derailleur seems to "catch-up" to the rear in small steps when shifting (correct?). If so, how many rear steps per front adjustment? Is this controllable?

I realize that most of these questions could be answered in the bike mechanics forum, but I find that most of the nice & smart folks hang out here.

Thanks again.

twocicle

Here: https://www.amazon.com/gp/product/B00...ilpage_o08_s00

Yes, both Di2 FD and RD can be adjusted. Each have in/out limit screws, plus the ability to tweak derailleur alignment electronically.

How-To is in the Di2 Manual... see page 52:
https://si.shimano.com/php/download.p...001-02-ENG.pdf

Youtube... example videos:
https://www.google.com/search?q=yout...utf-8&oe=utf-8

Fallback plan: Your dealer should be able to show you how, especially since that is what you paid them for... local product support.

oldacura

I had looked at several YouTube videos. I'll check the link you sent. The dealer we bought the bike from is not local. He's is one many on this forum recommended. He is trying to be of assistance but he can't put hands on. I don't know that is mis-adjusted. I figure that I will eventually need to know how it works so I can work on in the future. Does anyone else run a range this wide with "perfect" operation?

akexpress 

The small/small on 11 speed Di2 is rather hard to prevent cage rub on the front derailleur especially if you have 145mm spacing. It is very light on our 135mm spacing and also tends to rub slightly on the large chainring just because of chain angle. Really not any need for this combo and also leads to lots of chain slack especially with running an 11-36. Are you running a K-edge mod or a road link?

oldacura

K-edge

The attached photos show 52t x 36t (rarely used but necessary to ensure against accidents), 34t x 11t (rarely used but need for wider range). It also shows the front der cage with respect to the big ring and a view from above of the front cage.

rm -rf

I don't have a tandem, but this may answer some of your questions.

The Di2 dealer manual pdf is easy to follow. Very useful.

Setting the rear derailleur is basically: Put it in cog 5, hold the button to go to adjustment mode, then "micro-click" until it rubs on the next cog, then back off 4 clicks to center it. I think I later adjusted it by one more click to make the downshift a little smoother. (see page 52+ in the manual)
Download the manual here:
si.shimano.com/#seriesList/51
Di2 limit screw adjustment methods are different than mechanical derailleurs. Read that section if you are adjusting them.

The "long press" on the rear shift buttons can be set to go all the way across the cassette, but that's not very useful. I changed mine to be "shift 3 cogs" on a long press, which is holding the button more than 1/2 second. That's useful when shifting the front: hold both bottom buttons to go small chainring and 3 smaller cogs. Both top buttons do the opposite. You need the free "e-tube" software to connect the Di2 usb to your PC to change these settings.

Perhaps your front derailleur isn't perfectly adjusted if you are getting rubbing. It's easy to set, follow the manual.

The front derailleur auto trims in three steps as you shift the rear cogs. I don't know of any adjustment to this, and you shouldn't need any. In my 34-11 small-small combination, the chain "ticks" against the big ring pickup pins, but it still works.

Protecting the signal cables
They look fragile, but seem to be quite strong. I was removing my rear derailler to check the dropout frame bolts, and forgot to unplug it. It dropped unexpectedly, yanking the cable. But the cable unplugged from the derailleur, and was fine.

You do need the small plastic tool to unplug and replug the cables. They need to plug in with a click. You should have gotten it with your bike.


Rattling in the frame
I would pad any junction boxes that are inside the frame, and see if that fixes it.

mtseymour

You should avoid a 52T x 11T or 34T x 36T gear combo whether you're using Di2 or mechanical shifting. It will really stresses the chain and may cause chain suck. Once your Di2 is properly adjusted, your shifting technique will change because it's so quick and reliable. With your old bar-end shifters, you may stay in a bad gear combo because it may be dicey to drop into the granny. With Di2, you can easily find the right gear combo and will barely slow down your cadence when shifting from the big ring to the granny (and vice versa). You may even shift the rear and front simultaneously on some occasions.

Does your crankset allow you to fine-tune the chainline? With our Lightning crankset, we used spacers to optimize the chainline. Regardless, my stoker will remind to shift when we're in a bad gear combo.

oldacura

Don't know if I can optimize the chainline. They are FSA cranks.

I'm now realizing that with my old non-indexed front derailleur, I could infinitely trim the front. It looks like with indexed shifting (mechanical or Di2) trimming is impossible - correct?

The reason we got the wide range is to be able to climb & descend steep hills. I realize that it is best to avoid big x big & small x small but why should we try to avoid big x small or small x big? Why would this stress the chain?

79pmooney

You mean 34T X 11T and 52T X 36T, no? The cross-over combinations.

Ben

mtseymour

You're right, Ben. This is another reason to have a stoker.

twocicle

Ah, but you are missing one of the great features of Di2. The Di2 derailleurs are auto trimming. It is cool to watch the FD move automatically in/out as you shift the rear cogs from one end of the cassette to the other. It is a "set and forget" system that works excellently on a tandem. No more fiddling with trimming while riding... if you want that, you shouldn't use Di2! Actually, once or twice I did adjust the trim while we were riding. Simple to do by pressing the button on the front junction box and tapping one of the shift levers, then exit the trim adjustment mode. Otherwise, once you get it adjusted, you can enjoy the ride so much more.

Rule of thumb about gear combos is to never use the small front/smallest 2 rear cogs, and very seldom if ever use the big ring / biggest cog combo. This is especially true with a wider cassette like these 11spds because the extreme ends result in a very sharp sideways bend in the chain (bad!). I think the mtn XTR Di2 derailleurs actually prevent one from going into the small/small combo. No such limiter on the road versions.

akexpress 

+1^

oldacura

I printed & read some of the Di2 manual.

Let me know if I am understanding the operation correctly:

Let's say one starts with small front cog & big rear cog. As one shifts the rear derailleur toward the outside (smaller cog), the front derailleur will make compensating (trimming) moves toward the outside every several shifts. Correct?

If correct, about how many rear shifts will cause the front to move? About what percent of a full shift is each of these trimming moves? Is this trimming move user adjustable?

Thanks

twocicle

yesFD will move 3 times if I recall correctly. From memory (guesstimate) I think the first FD movement to the outside will occur when shifting the rear from cog 4-5, then maybe the next trim at cogs 7-8 and lastly 9-10 being the furthest outboard it can go. You cannot adjust at which cog the FD trim will occur.

The FD alignment adjustment (page 58) in the big chainring and biggest rear cog is the only position where you can make that adjustment. Whatever you choose in that position will effect how the FD sits in all other trim positions.

Note the install guide indicated that FD alignment parallel to the chainrings is a crucial factor. That is a good starting point, but I find tweaking the alignment a touch outward provides the best clearances (eliminates chain rub on the FD). You can adjust the FD alignment either by moving the seat tube clamp, or to some degree with the FD support bolt.