I just replaced my bike’s crankset, bottom bracket and chain because I got a bigger crankset. I also adjusted my rear and front derailleurs.
I have a problem with this new setup where my chain skips only when using the configuration mentioned in title. This only happens sometimes when I push very hard on the pedals, it’s hard to do so consistently. You can’t see it happening in the vid as I can’t push that hard with my hands.
I had my cassette last replaced in August 2025(also my chain), I check from time to time the wear of my chain and I don’t bike in winters so the problem being a worn cassette doesn’t make too much sense. However I do bike pretty often with the small gear in the back.
I don’t bike that frequently as my bike is broken half the time.
Can someone please tell me what the problem could be? I am praying for this bike to go 1 month without having to undergo a repair.
Chain skipping when big gear in front and small gear in back
byu/CombinationAsleep219 inbikewrench
by CombinationAsleep219
4 Comments
You say you bike pretty often with the small gear in the back, which makes me believe you may be sitting in it consistently. Does this issue arise mostly/only when starting from a stop in that smallest gear?
If you’ve also moved to a larger crank set, then you are also increasing the forces on to that cog.
Very frequently I see people on e-bikes making the same complaints as they don’t feel the need to shift and then they end up having worn down the smallest cog, and though hard to see visually, often causes this skipping.
TL;DR Much like a car you, you don’t want to be starting from a stop in your highest gear, as it is incredibly hard on the parts
If this isn’t the case, I’ll follow up.
New chain and old cog is my guess. There’s a tool that measures if a cog is worn, but a new chain usually reveals it.
“I also adjusted my rear and front derailleurs.”
What did this adjustment consist of?
If you just replaced your chain and it skips under heavy load in the 11t, your cassette is worn out. This is likely because your old chain was overdue to be replaced. The old chain would have fit well enough since they wore together, but it’s not going to work with a new chain.
Clapped cassette. Time for a new one