Tiagra77

Hi guys. I hope everyone is doing fine. I have a problem with my road bicycle. The chain skips and there is a little friction when the chain is in the middle of the crankset. I changed my chain and cassette and paid for a derailleurs adjustment at the end of last summer. I didn't use this bike on winter. The cable tension seems to be okay. Someone know what it could be and how to solve it please ? Thanks.

Rolla

Does the chain skip on the chainring or the rear cogs?
When you say "middle of the crankset," do you mean the middle chainring on a triple?
What kind of "friction" are you experiencing? Is the chain rubbing on another chainring?
How have you determined that the cable tension is okay?

Without knowing the answers to those questions, it sounds like the chainring might be worn. How are the teeth?

Iride01 

This needs a little more clarification. What do you mean "little friction"? And I'm guessing that this is a bike with three chainrings on the front crank.

Did you ride the bike any amount after it was serviced last and have to pedal hard while in that gear combo? Pedaling hard tends to expose worn out rings or cogs by letting the chain skip on them after a new chain is installed

It is common that if you let a chain get very very very worn out before changing it that the chainrings you ride in the most will also need replacing. However I wouldn't fault the LBS for not seeing that. So if you aren't a DIY type, I'd recommend that you just go back to the LBS or another LBS and tell them your issue. Depending on your crankset, it might be a lot or a little to replace that ring. Sometimes you are better off with a entirely new crankset.

But by no means is what I'm describing the problem. There are many things it could be from what little we know about your bike and the actual issue you are describing.

Tiagra77

The friction comes from the front derailleur on some speeds. Yes I mean the "middle chainring on a triple".

It looks like another problem comes from the bottom bracket who seems to be loose and dirty but I am not sure. I don't have the competence or tools to remove it, clean it and grease it. However, I cleaned it from the outside but is it a good idea to oil it too (from the outside only) ? Thanks

I think I am gonna go to another LBS and I hope this time he will be able to solve all this.

Rolla

No, don't oil the BB from the outside. If you can't diagnose the problem(s) and lack the tools and knowledge to do the work yourself, follow your instincts and take it to a good shop.

bbbean 

The very first thing you should check is rear derailleur indexing. Here's a great video from Park Tools showing how to do it:
FWIW, even though you had it serviced last summer, cables stretch, derailleurs get bumped, wheels get remounted wonky, etc. Tuning your derailleurs periodically is just part of the repairs and service a bike needs from time to time.

BB

bbbean 

Oh. In that case, see THIS video: