Troubleshooting indexing on 34-11t rear cassette

k1banjo

I just recently put a Shimano 34-11t rear cassette on a cx bike. I changed the Ultegra Rear Derailleur to a long cage Tiagra 4700 GS (both 10 speed). Ultegra 10 speed shifters. Chain length is good. Limit screws are adjusted properly. Derailleur hanger is straight. Here is the problem. I cannot get the shifting adjusted properly to accomodate BOTH the 34t and the 11t cog. When I adjust it to where it will go into the 11t cog, there is not enough cable tension to get it to "stay" in the 34t cog. When I adjust it for the 34t cog, there is too much cable tension to shift down to the 11t cog. I would appreciate any help. Thanks

flycop2000

The cassette is defiantly a 10 speed?

svetty

The Tiagra 4700 rear mech isn't compatible with Ultegra 10 spd shifters.......

k1banjo

Thanks...after a little investigation, I believe that you are correct about the shifters.

kangarouge

Am I right in suggesting that it's not good practice to use the 34 and the 11 together as the chain cross is not good?

Matthewfalle

Kangarouge wrote:

Am I right in suggesting that it's not good practice to use the 34 and the 11 together as the chain cross is not good?

How do you mean? The 34 is at the top of the cassette, the 11 is at the bottom so they can't be used together.

webboo

Maybe he means 34 as on a compact.

kangarouge

I was thinking he is referring to 34 on the compact chainset too.

Bumo_b

The cheapest way round this, is to get an older Tiagra rear derailleur. The Tiagra 4600 derailleur has the same pull ratio as your shifter, but it all changed with the new 4700 group set. If I had to hazard a guess, you are struggling with the jumping on the middle of the rear cassette? As for being on the 34t front chain ring and 34t rear cog, that is fine. If using the 11t rear and 34t front, that is not good, not that it has stopped me from doing it from time to time, but will shorten the life of components, and definitely the chain. Don't forget to get your chain length right, and the B screw tension becomes a lot more important.

trekvet

Kangarouge wrote:

Am I right in suggesting that it's not good practice to use the 34 and the 11 together as the chain cross is not good?

This is basic cycling "not good practice", so why would you want to do it? The more the chain is crossed the greater the friction (and so wear), which means, conversely, that a straight chain can give greater speed for the same effort. I find once I can hear what's happening down there that it's overdue for sorting it out.