New OG-1070 Cassete skips on large cogs

acideraser

Hi. I've a got a new Spec Tricross with Ultegra RD, FSA Gossamer crankset (48x34) and OG-1070 SRAM cassete -
11-12-13-14-15-17-19-22-25-28
I use only the large chain ring (48) most of the time. The rear derailer shifts perfect but when I got to lower gears climbing a hill - 22 and up - my chain starts skipping teeth and this makes climbing difficult.
Does anyone know why is that - is it because the chain gets bend large chainring front and large sprockets in the rear, or because of Open Glide construction of the cassette or some other reason?

Has anyone experienced this kind of problem with this cassette?

Thank you very much for help

topdude

Why on earth would you want to use the largest chainring and largest rear sprockets for climbing hills ?
Change down to the 34 and the nice straight chainline will stop the skipping of teeth :roll:

John.T

Topdude is right. Get off that big ring on climbs. You should not have chain slip however. Check that your indexing is not just a little bit out. It does not take much for the gears to try to auto change. Make sure the cable is clean and well lubed.

acideraser

Thanks guys. This si new bike so all is in perfect condition.
Will use 34 for long hills

cheers