Hydraulic Brake Problem...

"Mark Taylor" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

I've noticed that my Hydraulic brakes have 'lost' adjustment and are only
needing a very small amount of pull on the brake levers to apply them. The
brake levers are freely moving and there are no problems there..The brake
system is the 'Giant MPH system and is on a Giant XTC 840 Cross Country
mountain bike. The bike is about a 2002 model I think, however I've only
had the bike from new about a year.

One thing I've done which might(?) have affected the set up is to change
the handlebars, hence move the positioning of the brake levers. This
problem is causing a concern as in hot weather, if the bike is left in
direct sunlight, the brakes tend to apply themselves which is resolved by
leaving the bike in the shade.

The system has an adjustment wheel on each of the brake levers to open or
close the spacing between the disk and the pads, but I'm only getting no
more than half a turn off each adjustment wheel when I used to get
several.

I (in my layman capacity!) wonder if me moving the levers has upset the
system..???

If anyone can help me it would be appreciated as I'm having a cycling
holiday in 2 weeks and really want to get it sorted before I go..!!

Mark Taylor

Mark,

I have had a similar problem with my Giant MPH brakes - an inability to
'back-off' the adjuster enough in hot weather. It was resolved by removing
a small amount of brake fluid from the reservoir.

John Wilton

Thanks John,

Was this a difficult thing to do? If it is a simple task, maybe you could
describe the process?

Thanks,

Mark

"John Wilton" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

"Mark Taylor" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

I've noticed that my Hydraulic brakes have 'lost' adjustment and are only
needing a very small amount of pull on the brake levers to apply them.
The brake levers are freely moving and there are no problems there..The
brake system is the 'Giant MPH system and is on a Giant XTC 840 Cross
Country mountain bike. The bike is about a 2002 model I think, however
I've only had the bike from new about a year.

One thing I've done which might(?) have affected the set up is to change
the handlebars, hence move the positioning of the brake levers. This
problem is causing a concern as in hot weather, if the bike is left in
direct sunlight, the brakes tend to apply themselves which is resolved by
leaving the bike in the shade.

The system has an adjustment wheel on each of the brake levers to open or
close the spacing between the disk and the pads, but I'm only getting no
more than half a turn off each adjustment wheel when I used to get
several.

I (in my layman capacity!) wonder if me moving the levers has upset the
system..???

If anyone can help me it would be appreciated as I'm having a cycling
holiday in 2 weeks and really want to get it sorted before I go..!!

Mark Taylor

Mark,

I have had a similar problem with my Giant MPH brakes - an inability to
'back-off' the adjuster enough in hot weather. It was resolved by
removing a small amount of brake fluid from the reservoir.

John Wilton

"Mark Taylor" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Thanks John,

Was this a difficult thing to do? If it is a simple task, maybe you could
describe the process?

Thanks,

Mark

"John Wilton" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

"Mark Taylor" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

I've noticed that my Hydraulic brakes have 'lost' adjustment and are
only needing a very small amount of pull on the brake levers to apply
them. The brake levers are freely moving and there are no problems
there..The brake system is the 'Giant MPH system and is on a Giant XTC
840 Cross Country mountain bike. The bike is about a 2002 model I think,
however I've only had the bike from new about a year.

One thing I've done which might(?) have affected the set up is to change
the handlebars, hence move the positioning of the brake levers. This
problem is causing a concern as in hot weather, if the bike is left in
direct sunlight, the brakes tend to apply themselves which is resolved
by leaving the bike in the shade.

The system has an adjustment wheel on each of the brake levers to open
or close the spacing between the disk and the pads, but I'm only getting
no more than half a turn off each adjustment wheel when I used to get
several.

I (in my layman capacity!) wonder if me moving the levers has upset the
system..???

If anyone can help me it would be appreciated as I'm having a cycling
holiday in 2 weeks and really want to get it sorted before I go..!!

Mark Taylor

Mark,

I have had a similar problem with my Giant MPH brakes - an inability to
'back-off' the adjuster enough in hot weather. It was resolved by
removing a small amount of brake fluid from the reservoir.

John Wilton

Mark,

NB My brakes are MPH-3 not sure whether yours are the same but...

It was some time ago but I seem to remember simply removing the plug on the
top of the reservoir , removing some fluid, reinserting the plug - job
done. Looking at the manual I wonder whether it would be better to just
crack the bleed nipple on the caliper, squeeze some fluid out then retighten
the nipple .

John

John,

Job done indeed..!!

Just loosened the plugs and allowed a couple of drops of fluid to leak out -
it seemed that the system was under pressure even with the adjustment wheel
fully open and without touching the caliper.

Everything's fine now and I've got full adjustment on both brakes.....
Hurrah..!!

Thanks for the help John - now I can go on this trip without the worrry of
the praked being fully locked up when I want to ride..!!

Mark Taylor

"John Wilton" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

"Mark Taylor" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Thanks John,

Was this a difficult thing to do? If it is a simple task, maybe you could
describe the process?

Thanks,

Mark

"John Wilton" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

"Mark Taylor" <[email hidden]> wrote in message
news:[email hidden]...
> I've noticed that my Hydraulic brakes have 'lost' adjustment and are
> only needing a very small amount of pull on the brake levers to apply
> them. The brake levers are freely moving and there are no problems
> there..The brake system is the 'Giant MPH system and is on a Giant XTC
> 840 Cross Country mountain bike. The bike is about a 2002 model I
> think, however I've only had the bike from new about a year.
>
> One thing I've done which might(?) have affected the set up is to
> change the handlebars, hence move the positioning of the brake levers.
> This problem is causing a concern as in hot weather, if the bike is
> left in direct sunlight, the brakes tend to apply themselves which is
> resolved by leaving the bike in the shade.
>
> The system has an adjustment wheel on each of the brake levers to open
> or close the spacing between the disk and the pads, but I'm only
> getting no more than half a turn off each adjustment wheel when I used
> to get several.
>
> I (in my layman capacity!) wonder if me moving the levers has upset the
> system..???
>
> If anyone can help me it would be appreciated as I'm having a cycling
> holiday in 2 weeks and really want to get it sorted before I go..!!
>
> Mark Taylor
>

Mark,

I have had a similar problem with my Giant MPH brakes - an inability to
'back-off' the adjuster enough in hot weather. It was resolved by
removing a small amount of brake fluid from the reservoir.

John Wilton

Mark,

NB My brakes are MPH-3 not sure whether yours are the same but...

It was some time ago but I seem to remember simply removing the plug on
the top of the reservoir , removing some fluid, reinserting the plug -
job done. Looking at the manual I wonder whether it would be better to
just crack the bleed nipple on the caliper, squeeze some fluid out then
retighten the nipple .

John