Shimano Altus c20 rear shifter issue - please help me thanks

[cyc715t]

Hi, how is everyone going?

I've run into a problem here...

I got a shimano altus c20 rear shifter that doesn't really want to engage properly and change gear. You have to flick the shifter many, many times before it starts to engage and change gear... once it does engage.. it works and goes up and then down but after it goes down to the smallest cog, it then does the same thing where you keep flicking the lever and it won't engage until about 20 or so flicks if you are lucky before it decides to respond and change gears to the bigger cogs.

The cable isn't slack or anything on the smallest cog and the screws are adjusted fine. What do you think the problem is and how can I fix it please?

Thanks in advance!

[high_tea]

Hi, how is everyone going?

I've run into a problem here...

I got a shimano altus c20 rear shifter that doesn't really want to engage properly and change gear. You have to flick the shifter many, many times before it starts to engage and change gear... once it does engage.. it works and goes up and then down but after it goes down to the smallest cog, it then does the same thing where you keep flicking the lever and it won't engage until about 20 or so flicks if you are lucky before it decides to respond and change gears to the bigger cogs.

The cable isn't slack or anything on the smallest cog and the screws are adjusted fine. What do you think the problem is and how can I fix it please?

Thanks in advance!

I'd be thinking about changing the cable.

[cyc715t]

what happens if it is not the cable please?

[high_tea]

The next most likely culprit, do you mean? The cable housing.

[simonn]

You have to flick the shifter many, many times before it starts to engage and change gear... once it does engage.. it works and goes up and then down but after it goes down to the smallest cog, it then does the same thing where you keep flicking the lever and it won't engage until about 20 or so flicks if you are lucky before it decides to respond and change gears to the bigger cogs.

The bureaucratic shift. You need to submit a proposal to change gear.

Dirty/frayed/corroded inner and/or outer cables

Have you been riding in mud/rain? Change your cables.

[cyc715t]

I didn't think it was the cables etc as it does change gear. The problem is I have to flick the lever about 20 times before it decides to engage and change gear. Once it does, it changes up and down each time but once it goes back to the smaller cog, the same thing happens again..where I need to flick the lever 20 or so times...

[kb]

It's possible your chain is too long and the pulley is getting caught on the rear sprockets when in your highest gear.

Still think it sounds like cables though.

[fooch]

It might also be the shifters. Are they the ones with two levers, i.e. Rapidfire? apart from what has been suggested above, all of which are good suggestions, you can also spray some WD40 or similar light spray lube into the shifter itself to dislodge the gunk buildup internally. This usually improves shifting.

[Dan]

5 internet dollars says its the cable. Or, you could ask for advice, then ignore it. That also costs five internet dollars.