Help with adjusting gears!

[raleighnut]

That's strange!
I watched the video to get an idea of how the gearing works (I know, I know!). I then lifted the back wheel off the ground (don't have a stand) and clicked through the gearing.
The bl**dy thing clicked into 1st fine! But when I'm riding and go to change down when I'm pedalling uphill, it just rattles around!

I will solve this....
Oh and I rode it around the garden...it wouldn't change up from 1st to 2nd!!

Try changing gear whilst still pedalling quite quickly, some mech's can be reluctant/slow to change when the crank is only turning slowly.

 

[Brandane]

Assuming the limit screws are properly set, which they should be if the gears worked fine when you got the bike and no-one has faffed with them since, then the most likely problem will be cable tension.
If the chain won't move to a smaller ring/sprocket, then the cable is too tight.
If the chain won't move to a bigger ring/sprocket then the cable is too slack.
If it is struggling to do both, then it is probably a damaged/worn/corroded cable and/or outer which isn't allowing the cable to slide as intended.
To adjust cable tension in small amounts, use the barrel adjusters at the shifter end, or the derailleur end, or somewhere in between!
If it needs a bigger adjustment than the barrel adjusters will allow, then the cable clamp on the derailleur is where to go.

 

[PatrickPending]

second the above, and the posted video is very good. Just shift to the smallest cog and click one up. It should be adjusted so that the mech just about shifts up. Things can get tricky with a frayed or sticky cable but as the bike is only 6 months old.....

 

[ScotiaLass]

Weird that it shifted down okay today!
I think it still needs adjusting as I can't rely on it shifting down when I need it.

 

[andrew_s]

The bl**dy thing clicked into 1st fine! But when I'm riding and go to change down when I'm pedalling uphill, it just rattles around!
Oh and I rode it around the garden...it wouldn't change up from 1st to 2nd!!

I'd guess that the cage alignment isn't right, so if it's a clamp-on front mech the whole clamp has twisted round the seat tube a little (braze-on front mechs have a similar adjustment). The mech should be positioned so that the outer cage is parallel to the outer chainring, and passes 1-2mm above it as it moves outwards.

The other thing that can help is to reduce the tension on the chain whilst you are changing front gear. This means changing down before your pedalling speed falls too far, or the loss of momentum whilst you aren't pushing during the change may see you stall. Those of us who took up cycling before chainrings developed pick-up pins, ramps and gates, and front mech sideplates were flat, had to do this all of the time.

 

[raleighnut]

Weird that it shifted down okay today!
I think it still needs adjusting as I can't rely on it shifting down when I need it.

It knows you have plans to fiddle with it, maybe even replace it so its being a good little changer.........................

 

[ScotiaLass]

It knows you have plans to fiddle with it, maybe even replace it so its being a good little changer.........................

That's what I thought! And she got treated to a handlebar bag and bottle cage/bottle yesterday too.
What it is they say? If it's got wheels or breasts, you've got trouble?