Chain drops onto down onto smaller

[User16390]

I have an 8 speed touring bike and recently noticed that when I have selected the fourth largest ring on the rear block (excuse me for not using correct terminology) and pull up at lights and then back pedal to move the pedal in position to pull off the chain drops down onto the next smallest ring on the block. As soon as I start pedaling forward it moves back up to the gear I selected. Also there is a really annoying tick tick noise when I am pedaling under load. I have checked the pedals and their is no movement as well as the bottom bracket.

Advice is most welcome

 

[david1701]

are the gears indexed? it sounds like an indexing issue. Is that ticking noise common through the gear range?

 

[User16390]

The gears are indexed and yes the ticking noise is common through the gear range.

 

[Pauluk]

Have you tried adjusting the cable tension either at the shifters or the rear mech

 

[TonyEnjoyD]

If you dont have gear problems normally the Back-pedalling will be the issue.
You need to select your gear nd pedal into it before stopping. Never back-pedal mid-shift

If you get caught and shift as you stop, lift the rear of the bike and spin the pedals forward to get it in the gear before setting off otherwise you are in a chain-splitting situation.

Hope this helps

 

[User16390]

I have adjusted the indexing and has appeared to ssort out the problem of the chain dropping, however the creaking noise when I am pedaling under load is still a problem. My brother who is a keen cyclist reckons it could be the bottom bracket, but I have checked and it appears to not to be loose. Pedals are fine.

 

[dirtjumps]

I am having what seems a similar trouble to this, When I switch into gear 3 and above, and pedal under strain, I get two clicks for ever pedal cycle I do (2 left, 2 right in one complete cycle) and occasionally gear slips down into a lower gear, what's indexing? Sorry I'm a complete novice :/