I bought a Dura Ace-build Planet-X Stealth Pro Carbon last week. Today when I did some serious inspections of the bike and again checked that everything work as it suppose to do, I discovered a problem with the Dura Ace rear derailleur. It doesn’t work properly, it’s not possible to use the smallest sprocket (11T). I tried to do some adjustments, but it doesn’t help. It’s impossible to get the chain on the smallest sprocket, the rear derailleur doesn’t move enough to the right to move the chain into the correct position. I have tried to change the top adjustment screw without any result… I have read the service instructions from Shimano, but it didn’t solve the problem… I’m a bit confused, it seems so simple, but it doesn’t work anyway, I hope someone can have an idea about what’s wrong.
If you’ve loosened the appropriate set screw and it doesn’t drop into 11 cog, then the wire may be too tight. Try screwing in the barrel adjuster on the dr. If that doesn’t do it, you may have to loosen nut holding down the wire.
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There is a retaining washer under the cable anchor bolt. It is twisted 90 degress and the “tail” of the washer is wrapped around the cable i/o just pinching the cable. There is a flat spot on the outer link for that washer “tail” to fit into the derailleur body, NOT to wrap around the cable. The cable is secured with a slightly oval lip that extends beyond the diameter of the shoulder of the cable anchor bolt.
The incorrectly installed washer is preventing the derailleur from dropping all the way down into the 11t position, the most “relaxed” postion of the derailler drawing the two links (outer and inner) together. The washer keeps them from contracting all the way.
I’ve got a quick tutorial for you if you want to send me a note via email, I can send you a .doc I wrote a number of years ago to identify and correct the incorrect installation.
Dear Sir,
Your most likely problem is that the rear der. tab is bent. It often happens in shipping or from the factory. Tabs are basically to be aligned so that the der. is neutral say 50mm from the rim, up and down, and slightly open to the front 47mm back to 54mm front. You can somewhat judge this from behind to see if the der. hangs that way, or obtain a der alignment tool and do it correctly.
Steve
SMp
I think the set screw (limit screws) on the derailleur would be obvious, the tell tale sign is to disconnect the cable, cable anchor bolt and retaining washer below the bolt altogether, then see if the rear derailleur drops into the 11t if it does, then the limit screw is not the culprit.
I hope to get an update, I sent him a photo tutorial on how to set up the rear derailleur.
Superdave is on the money. I have had this same problem. The tab on the washer faces the back of the derailleur and does not wrap over the cable. If it’s wrapped over the cable you won’t get that last shift.
Thanks for your help! I have changed the position of the washer and now it’s possible to shift to the smallest sprocket. I have done some adjustments and now the rear derailleur is working perfect!
I’m glad this worked and others have benefitted from your question. I have sent that .doc out 6 times already for others and it seems that they’ve had the same problem.
I’m glad that the derailleur is working fine now, but I’m really disappointed at my bike dealer, he should have installed the rear derailleur correctley from the beginning. I bought a completely new bike and expected that such a basic thing should work without any problem…
I’m sure it was a simple oversight on the dealers part. I wouldn’t crucify them on one instance. I’ve seen this happen a few times and it is often the case that it occurs just after an adjustment. I’m sure if you returned to your dealer they could have diagnosed and delivered the same result.
