Adjusting indexed gears

[Ben]

Hi,

I have a dawes Horizon 24 speed bike with STI shifters. Recently I had
the chain, freewheel, and rear cogs replaced as all were worn and the
chain kept skipping. Now things are much better, but there are two
minor problems still:

The chain still occasionally skips, which can be annoying especially
when you have weight on the cranks. But since most of the drivetrain
was replaced, what can it be?

The STI shifters seem to have a delay - I shift, and after a delay,
sometimes a few second, the gears change - I'm assuming this is a
problem with gear adjustment?

Any thoughts much appreciated,

Cheers,

Ben

 

[Eatmorepies]

"Ben" <[email protected]> wrote in message
news:[email protected]...
> Hi,
>
> I have a dawes Horizon 24 speed bike with STI shifters. Recently I had
> the chain, freewheel, and rear cogs replaced as all were worn and the
> chain kept skipping. Now things are much better, but there are two
> minor problems still:
>
> The chain still occasionally skips, which can be annoying especially
> when you have weight on the cranks. But since most of the drivetrain
> was replaced, what can it be?
>
> The STI shifters seem to have a delay - I shift, and after a delay,
> sometimes a few second, the gears change - I'm assuming this is a
> problem with gear adjustment?
>


Posible slight lack of tension in the cable. Wind the adjuster on the rear
mech out a half turn, try it and then repeat with another half turn if it
doesn't work.

The method used to get cable tension right is to hold the bike off the
ground in middle ring on the front and the second smallest on the rear. Turn
the pedals and turn out the rear adjuster until the chain is just trying to
move up to the next gear, then slack the adjuster off about half a turn - or
certainly until the clacking stops.

John

 

[Mike Clark]

In message <[email protected]>
Ben <[email protected]> wrote:

> Hi,
>
> I have a dawes Horizon 24 speed bike with STI shifters. Recently I had
> the chain, freewheel, and rear cogs replaced as all were worn and the
> chain kept skipping. Now things are much better, but there are two
> minor problems still:
>
> The chain still occasionally skips, which can be annoying especially
> when you have weight on the cranks. But since most of the drivetrain
> was replaced, what can it be?
>
> The STI shifters seem to have a delay - I shift, and after a delay,
> sometimes a few second, the gears change - I'm assuming this is a
> problem with gear adjustment?
>
> Any thoughts much appreciated,
>
> Cheers,
>
> Ben
>

Last time this happened to me it turned out to be the cable wasn't
running smoothly in it's sleave. In fact the cable itself failed after a
short period of time. Once it was replaced the gears behaved themselves.

Mike
--
o/ \\ // |\ ,_ o Mike Clark
<\__,\\ // __o | \ / /\, "A mountain climbing, cycling, skiing,
"> || _`\<,_ |__\ \> | immunology lecturer, antibody engineer and
` || (_)/ (_) | \corn computer user"

 

[Simon Brooke]

in message <[email protected]>, Ben
('[email protected]') wrote:

> I have a dawes Horizon 24 speed bike with STI shifters. Recently I had
> the chain, freewheel, and rear cogs replaced as all were worn and the
> chain kept skipping. Now things are much better, but there are two
> minor problems still:
>
> The chain still occasionally skips, which can be annoying especially
> when you have weight on the cranks. But since most of the drivetrain
> was replaced, what can it be?
>
> The STI shifters seem to have a delay - I shift, and after a delay,
> sometimes a few second, the gears change - I'm assuming this is a
> problem with gear adjustment?

It varies slightly from system to system, but the basic procedure for
adjusting indexed gears is

(1) if there is a cable adjuster on the shifter, screw it right in and then
back it out one turn;
(2) shift onto the middle cog at the back
(3) adjust the cable adjuster on the rear derailleur until the upper idler
wheel is exactly below the cog the chain is on

If there isn't enough adjustment in the cable adjuster on the derailleur,
don't make up the adjustment on the adjuster on the handlebar; instead,
slacken the cable clamp bolt on the derailleur, pull a little more cable
through, and retighten the clamp bolt.

The other thing which can cause problems is a cable which isn't sliding
smoothly in its sleeve. If you continue to have problems, replace both
cable and sleeve (they're cheap).

--
[email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/

;; Semper in faecibus sumus, sole profundum variat.