dnfcx

My chain seems to be locking up when I shift from my big ring to my little ring.

Ill be up in the 25 on the back and the 53 on the front and need to go down to my small ring.

Ill shift a few cogs to maybe the 17 or so in the back and get a few rotations in and then shift the front down.

about 1 in 10 times the chain locks up and I need to back pedal or whatnot to get the drivetrain going again.

Any idea what Im doing that causes this? Too low of a cadence? derailleur need help?

chado445510

That happens to me on my mountain bike sometimes. With me, the chain is getting stuck somewhere on the big ring, which makes it so it cannot shift down. I'm not sure if this would work, but just give your chain a good greasing and degreasing and check for wear and you should be fine.

DaveSSS 

If the 25 is your largest cog, you shouldn't be using it to start with. When you shift to the little ring, it's common to need to shift 1-2 cogs smaller, so quickly shift to at least one cog smaller, then make the chainring shift.

banerjek

If you're moving to the 17 or so before shifting rings, the chain should not be jamming up. If it is, most likely you need to adjust your front derailleur or do a better job maintaining your chain.

If you have a bike stand, mount the bike, and shift back and forth paying close attention to where it's catching.