Automatic shifting prob

[rich p]

gwhite, what you say makes sense wrt the default positions. If it hadn't happened 3 times I'd have doubted myself and my sanity!

Frank, I think you may be on the money there. Each time it happened I was on a slight down slope putting in a big effort so the flex would have been at it's greatest. I can't recall which downstroke it happened on but I have readjusted the tension again, replaced everything replaceable and now I'll suck it and see.

 

[Baggy]

From the title of this I thought you'd invested in automatic shifting and that you deserved to have problems for being a flash git

 

[MacB]

gwhite, what you say makes sense wrt the default positions. If it hadn't happened 3 times I'd have doubted myself and my sanity!

Frank, I think you may be on the money there. Each time it happened I was on a slight down slope putting in a big effort so the flex would have been at it's greatest. I can't recall which downstroke it happened on but I have readjusted the tension again, replaced everything replaceable and now I'll suck it and see.

Is that a technical term or is it just a result of age and tooth loss?

 

[rich p]

Is that a technical term or is it just a result of age and tooth loss?

Cheeky sod! I haven't lost them at all; they're in a glass on the bedside table.

 

[deaksie]

Hi Frank, Rich
please accept my apologies - I didn't mean to upset anyone! I just thought given it was a similar issue it might be good to keep them together, but I shall know for next time.
thanks for the tips guys
L

 

[david1701]

the cables section of this sheldon brown mentions your auto shifting issue I think

Another problem area is the cable guide where the cables run under the bottom bracket. In addition to sluggish upshifting, friction in this area can cause spontaneous upshifting under load.


so cleaning and oiling that area sound like a winner?

 

[mickle]

Is your front mech 'top normal' or 'bottom normal'?

 

[gwhite]

the cables section of this sheldon brown mentions your auto shifting issue I think

Another problem area is the cable guide where the cables run under the bottom bracket. In addition to sluggish upshifting, friction in this area can cause spontaneous upshifting under load.

so cleaning and oiling that area sound like a winner?

Sheldon is speaking about the RD here where the spring tension is towards the small sprockets. If the cable is not free-moving then a sudden release of tension allows the spring to move the Der towards the small (high) sprockets. Cannot see this being the case on the FD where the spring tension is pulling towards the small ring i.e. inwards.

 

[mickle]

Sheldon is speaking about the RD here where the spring tension is towards the small sprockets. If the cable is not free-moving then a sudden release of tension allows the spring to move the Der towards the small (high) sprockets. Cannot see this being the case on the FD where the spring tension is pulling towards the small ring i.e. inwards.

I refer the right honourable member to the answer I gave 'a few moments' ago.

 

[david1701]

Sheldon is speaking about the RD here where the spring tension is towards the small sprockets. If the cable is not free-moving then a sudden release of tension allows the spring to move the Der towards the small (high) sprockets. Cannot see this being the case on the FD where the spring tension is pulling towards the small ring i.e. inwards.

I just passed it on in case it could help, went over my head by quite a bit.

 

[mickle]

A very few front mechs are 'top normal', I've got one on one of my bikes.

 

[gwhite]

A very few front mechs are 'top normal', I've got one on one of my bikes.

Really???????

I think that I'm going to give up fixing bikes. I never knew that such a beast existed.

 

[mickle]

Sachs Quartz