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Ghost shifting (shimano)

11K views 23 replies 12 participants last post by  Johnny Bravo 
#1 ·
Hi all

I recently purchased a 2011 Felt F1 frame and built it up with components from the bike I rode in 2011

(For reference I used Dura Ace Di2 with about 3000 miles on it)

I replaced the chain but not the cassette

I now have some intermittent ghost shifting issues

Mostly in the small ring, in the middle of the rear cassette - mostly when climbing or under torque

Happens 3-4 times over the course of a 65 mile ride

The shifting otherwise seems pretty much solid - very crisp and quiet - so I don't think the adjustment is an issue

I have Cosmic Carbone SLRs and I used a spacer before adding the cassette

I am tempted to buy a new cassette but advice is welcome

I am wondering also - if I buy a new cassette - will I need a new chain - chain is new - maybe 200 miles

Thanks

Would love to get this sorted out before a race next weekend!
 
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#2 ·
One other thing

If you made it through the first post ...

When I installed the chain I cut it short and then had to break the chain and add links - had to use a shimano link from 7800 chain (I think)

Seemed to work just fine

THanks
 
#4 ·
You can almost eliminate all the usual suspects with Di2. My first guess would be a bent derailleur hanger..
 
#5 ·
Are you referring to actual 'shifts' in the cassette or intermittent 'clicks' of the chain as it latches onto the ramps of the cassette and then drops off?

If its the latter, possibly its the chainlink.

I had a similar issue with my bike (Colnago EPS) with DA Di2. Was using the original Shimano 7900 quicklink. Couldn't resolve the issue completely from fine tuning the adjustments with the Di2.

Swapped out the quicklink for a KMC one, did one adjustment for it and it was all cleared.

The DA Di2 is quite finicky with the chain. Especially if you're using the 7900 chain as its directional.

You could swap out to a chain which is completely uniform and see if you still have the same issues. KMC x10SL works good on Di2 btw ....
 
#6 ·
Thanks for the replies

The derailleur hanger doesn't look bent

I can't tell if there are actual shifts - it feels like the chain is slipping

I agree that I think it is unlikely to be the cassette - is there any way to test for wear?

I am not using a quick link - just the supplied connector pin - one from the 7900 chain and an older one from a 7800 chain

Thanks
 
#8 ·
It sounds like what I described above. Either that or you should check your freehub ratchet.

Quick check is to go to your LBS and ask to borrow a good condition chain of the correct length with a good quick link. And go for ride to see if you have the same issue.

While there, you could ask them, if they are willing to do the favour to check your wheelset freehub ratchet.

Note too: the RD hanger straightness can't be discerned just by the naked eye. Many people, even mechanics have issues with this!
 
#9 ·
I definitely don't think that it is the freehub ratchet

It sounds like the chain is trying to shift but doesn't

I don't know how to evaluate the derailleur hanger - but it is a brand new frame and there did not appear to be any damage shipping etc

I can feel the pin sticking out of the chain in two places where the links were added - just a tiny bit

Doe one need to use a special chain tool for this chain?
 
#10 ·
If the chain is what you describe, it most probably is the culprit. Its a phenomenon which probably prompted Shimano do do away with the quick link in its chains after initial launch. Like mentioned, the system used with the 7900 series chains are a little finicky when it comes to chain.

That tiny bit of chain is probably the cause. It latches onto the cog ramps and then drops off.

A standard Shimano 10-speed compatible chaintool is fine. But the pin just needs to be the correct one as between 7900 and 7800, there seems to be some differences as you'll notice that the 7900 chains have a perfectly flushed facade for the pins compared to the 7800.

If you're not sure, ask your LBS if they can help on that. I'm sure they have the 7900 pins. Or ask them for the KMC quicklink for Shimano 10-speed. Its probably US$7-8 at the shops (if the price is internationally homogenized) ...
 
#11 ·
Thanks for all the replies

I have bought a KMC chain - so waiting on that

My chain tool is a Park chain tool from the mid-90s, so before the era of ten speed drive chains

Is this my problem?

Also - my chain did not come with the quicklink - it came with a chain pin

Unfortunately I removed too many links, installed it, and then had to break it, and add additional links

Since there was only one 7900 chainpin, I had to use older chainpins (7800?) to attach the additional links

The instructions for 7900 chain recommends that the chain not be broken where the 7900 chainpin is installed so the chain now has three chainpins - one 7900 and two 7800

Anyway I will probably start by installing the new KMC chain

I will also purchase some 7900 pins - should I also get a new chain tool for 10 speed chains? Any recommendations?

I am plenty happy with 10 gears - I am not sure we need to keep going to 11 , 12 13 etc
 
#17 ·
Good call on the new chain. Try to flex the joints where you broke and see if its as flexible as unbroken joints. Its very easy to not have the pin in all the way or just a tad too far.

Edit geeze i really need to pay attention to the dates on these posts. There goes my 2c down the drain
 
#12 ·
Actually, I used a Parktool chain tool from back in '94, when I first bought it. But its different for me as I used it only for breaking and not re-linking after moving to the 10-speed system. So its not an issue on my system as I use the KMC quick link. But I have attached 2 or 3 chains for friends using it on the 6700 mechanical system. But no issues to date were reported though. But of course, they were using the specific pins meant for the chain.

The pin and chains breaking part are standard actually for any chain.
 
#13 ·
Have had this happen. Shifts great everywhere except two middle rings. In those one would shift up and then back down on its own. Faster if under load like uphill. The other would just sometimes go back and forth. With adjustments I could move it up or down a cog, but two side by side shifted on their own. Fix was adding one more link though there was nothing 'wrong' about the length to start with. Added link, fine tuned the derailleur, everything good and smooth as silk.

This was on brand new 105 everything with a Ultegra chain.
 
#16 ·
sorry for bringing this thread up again, but it was the only one I found about Di2 problems - and I think now the problem is happening to me

history: 2 years old external wired DA Di2 installed on a Scott Addict R2
bike used almost daily, 30-80mi/day (depending on training schedule)
for the last 30 days I haven´t cleaned it up and the bb area (and wires) is very very very dirty (dry mud, it´s been raining sometimes)

2 days ago I noticed something was wrong, but it happened only 3-4 times and then stopped
but today the problem showed up frequently and I could replicate it at home
I thought it could be the battery, but I charged it and the problem is still there

here´s what´s happening:
everytime I shift the RD, it moves the chain to the next sprocket correctly - BUT after a few seconds, the junction box blinks red twice and then the derailleur moves by itself again in the direction I had shifted before (up or down) - causing another (unwanted) shift...
my RD is ghost shifting!!!

I would really appreciate some help here...
 
#18 ·
JB...sounds like operator error. You most likely have your RD in crash recovery mode. Read the Di2 instructions. When you push the button on the junction box the RD first goes into adjust mode. If you hold the button in longer it goes into recovery mode, shifting through the entire cassette.

To check charge you push any of the shift buttons until the battery indicator light comes on.

While the written directions are very clear, having that button on the junction box makes you think that it's the battery checker. Ask me how I know :)

Best of luck.
 
#19 ·
thanks for the reply, Wheelman55
but it´s not operator error... it´s really deffective
i am an experienced user

it started happening once in a while, now it happens everytime i shift
when i do, some seconds later the light blinks red twice and shifts espontaneously one or two more cogs... either up or down
 
#22 ·
Same issue as you JB!




I'm having the same issue with "ghost shifting." I noticed a jump a couple times on a ride over the weekend. Last night it started really acting up exactly how you were explaining. I couldn't find any info on it. I called shimano and they said that I need to take it to my LBS and get it hooked up to the tester, that is, if they have it.

Did you get anything resolved with yours???

Thanks
 
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