Help! Chain stuck down by bottom bracket

[livpoksoc]

Got to work and parking the bike on the racks, and my chain has slipped off at the front but sat snug by the bb under the chainrings. I tried to free it with hands (usual cursing, grease and blood).

Is it a job that can be done delicately without tools, or am I off to the LBS at lunch?

 

[Cycleops]

A large screwdriver is your friend.

 

[livpoksoc]

A large screwdriver is your friend.

Just jam it in there and wiggle it about?

 

[Cycleops]

Here's a video:


View: https://youtube.com/shorts/V1djhrymuI4?si=rZJSnfacwnwKQ_4-


If you can't remove it with your hands use the screwdriver to prise it out of the gap.

 

[si_c]

Might be helpful to post a picture just so we can see what's going on.

Usually I find that dropping the gear to the lowest chainring and then upshifting whilst pedalling will solve the problem, but if it doesn't then it's likely the chain is catching on the chainring bolts as you try to lift it up. Try repositioning the chain from the underside of the bike instead, you can tension the derailleur that way so you aren't fighting it and then use your other hand to guide it into place.

The chain slipped down there easily enough so it will come out, you don't need to use a screwdriver - I'd avoid that if possible - but you may need to get both hands dirty.

Edit: @Cycleops found a video that demonstrates what I was talking about with greater clarity than I was capable of!

 

[Yellow Saddle]

Just jam it in there and wiggle it about?

Some imagination and hand cleaner is required.

 

[livpoksoc]

Ok thanks. LBS haven't got time, so going to give that a quick go.

I did try to drop the shifter down, pedal it to free it, but I think that made it worse. But maybe I was too keen shifting it up again.

Failing that, I can nip to decathlon and get a pair of KMC pliers to open the chain up and try and coerce it out without the tension.

 

[cyberknight]

Just jam it in there and wiggle it about?

@Fnaar

 

[Paulus]

Sometime with the large screwdriver method it can be worth rotating the cranks to help ease the chain out.

 

[livpoksoc]

Screwdriver method no good. Switching to guns.

 

[Cycleops]

Needs to be quite a large /long one to get the leverage. If that doesn't work you'll need to remove the crank which should be quite easy.

 

[livpoksoc]

KMC removal tool was gin. Chain fell out almost immediately and reattached.

Shame our work's wonderful bike park has a lot of tools and workstations, but no chain break/kmc tools. Will leave this one here for the next idiot.

 

[cyberknight]

KMC removal tool was gin. Chain fell out almost immediately and reattached.

Shame our work's wonderful bike park has a lot of tools and workstations, but no chain break/kmc tools. Will leave this one here for the next idiot.

at least you have a bike park that has facilities

 

[livpoksoc]

at least you have a bike park that has facilities

100%. Our company have invested well. It means I have ditched the tube.

We have about 20 showers (private cubicle with changing area).

2 x work stands with tools

2 x bike wash with drainage

Stretching area

Water coolers & vending

Chunka of lockers.

 

[cyberknight]

100%. Our company have invested well. It means I have ditched the tube.

We have about 20 showers (private cubicle with changing area).

2 x work stands with tools

2 x bike wash with drainage

Stretching area

Water coolers & vending

Chunka of lockers.

We have changing area , lockers and showers but as think more like old school gym changing rooms with shared showers as you can come out of work smelling grotty and dirty .I smell worse after a day at work than from cycling in .