Changing gear automatically

[potsy]

My bike has recently started going from middle chainring to small all by itself,only happens every now and again but is very annoying when it does as there is obviously no warning,and one minute I'm happily pedalling away the next my legs are spinning furiously

Is this just a case of a tweak of the adjuster?

 

[Fran143]

My bike has recently started going from middle chainring to small all by itself,only happens every now and again but is very annoying when it does as there is obviously no warning,and one minute I'm happily pedalling away the next my legs are spinning furiously

Is this just a case of a tweak of the adjuster?

Potsy,

That happened to mine at the weekend, jumping from big to small but had just changed rear inner tube so think I've shoogled it. Fiddled about with it but not actually taken it out for a spin yet hoping it'll be okay. Flamin Sectuers!

 

[fixedfixer]

Twist adjuster anti clockwise just one notch and see how that goes. Sounds like the cable has stretched a little or some wear in the system.

 

[Cheule]

Also, the bottom bracket is not worn is it? Causing the chainrings to wobble a bit left-to-right?

 

[PpPete]

Also, the bottom bracket is not worn is it? Causing the chainrings to wobble a bit left-to-right?

highly unlikely IMHO

 

[Cheule]

highly unlikely IMHO

I had to ask as my BB was so badly worn, this sort of thing was happening to mine.