Hope Mono Trial Problem

[dec]

hiya everyone i have just bought a hope mono trial 07 no new but of a mate

and when i pull the lever the one piston moves the most and then they dont retract i have took the wheel out and pulled the lever so that the pistns are exposed and then i pu a bit of lube on them and they are a bit better but they still dont retract so what is wrong do i just need to bleed it or what does it need new pistons or seals or what

quick responses would be very much appreciated cheers dec

[forteh]

hiya everyone i have just bought a hope mono trial 07 no new but of a mate

and when i pull the lever the one piston moves the most and then they dont retract i have took the wheel out and pulled the lever so that the pistns are exposed and then i pu a bit of lube on them and they are a bit better but they still dont retract so what is wrong do i just need to bleed it or what does it need new pistons or seals or what

quick responses would be very much appreciated cheers dec

New set of seals

Just done one of my old mini calipers, had the same symptons and new seals and bleed sorted it. You will need to get the tool to undo the piston plug or take it to your nearest hope dealer to get them to do it. On the mini the seals were just square section o-rings, cant see the mono trial being any different.

When you put the pistons back in lube them with some fresh brake fluid and they will pop into the seals easier

[Al_Fel]

if you've been pulling the brake without the disc in then because its an open system the pads will stay out. what you need to do is jam a screwdriver between the pads and push them back. Be carful though you don't ruin your pads.

The reason the pistons stay out is because its and open system and they stay out to adjust for pad wear.

hope this helps.

[dec]

thanks boys

i have tried putting the screwdirver between the pads and puchign it out and it did not work it was like something was stopping it

so i think a new blead and new seals is in order

cheers dec

[forteh]

thanks boys

i have tried putting the screwdirver between the pads and puchign it out and it did not work it was like something was stopping it

so i think a new blead and new seals is in order

cheers dec

Youre probably not pushing the pistons square enough if theyve jammed, you also probably have a bit of dirt behind the seals; only needs to be a tiny spec to jam it all up

[dec]

ok basically i have tried to lube up the pistons and they are a bit better but when i out my wheel and disc back in when i pull the lever well nothing happens and i dont no what they hel is going on.

also when i had the wheel out i out the lube on the pistons and squezed the lever i could hear and see some air bubles coming from around the piston so i think my seal have gone some more help would be very appreciated

dec

[forteh]

ok basically i have tried to lube up the pistons and they are a bit better but when i out my wheel and disc back in when i pull the lever well nothing happens and i dont no what they hel is going on.

also when i had the wheel out i out the lube on the pistons and squezed the lever i could hear and see some air bubles coming from around the piston so i think my seal have gone some more help would be very appreciated

dec

Only thing to do is put new seals in, either phone up hope for some more or talk to your local dealer, iirc the seals for my mini caliper were about 5 quid

Getting the bore plug out without the right tool could be interesting though - hope can supply you with one though.

edit:

Exploded view of the mono trial caliper.

And the bore cap tool.

Edited March 13, 2008 by forteh

[TrAsHeR]

Didn't read the hole topic.

But if your problem is that you pressed the lever with nothing between in,

and the pads are stuck together.

Then put the bike up and turn the reservoir (the bit on handlebars)

that contain the fluid up 90 degree.

Then open it but make sure you do that carefully or the liquid will come out.

So take the top metal bit off and the plastic seal underneath it.

And then take a screw diver, stick it between the pads and turn it to make the retract.

Close the reservoir and your done.

[forteh]

Didn't read the hole topic.

But if your problem is that you pressed the lever with nothing between in,

and the pads are stuck together.

Then put the bike up and turn the reservoir (the bit on handlebars)

that contain the fluid up 90 degree.

Then open it but make sure you do that carefully or the liquid will come out.

So take the top metal bit off and the plastic seal underneath it.

And then take a screw diver, stick it between the pads and turn it to make the retract.

Close the reservoir and your done.

You dont need to take the resevoir cap off to push the pistons back in, leave it on

If you read the whole topic you would find that his seals have failed and have admitted air into the system

[basher]

Cba replying to to ohers replys ect, best thing to do is

Lube the pistons up like you did or just blast them with oil, if that doesnt work and they still seem stiff the pistons take the out and clean and lube them and rebleed, seals should be ok as its not a old brake.

Get a screw driver or something and push the pistons all the way back, try to do it squarely as other wise they might go in at a wonky angle and give yu abit of hassle if they get jammed. Now set the brake back up and pump the brake loads of times and slowly the pads will move closer and closer and eventually your brake will feel fine.

Disk dont work like maggie where the pistons retract after going out they stay out thats why you should never press you frotn break when your wheel is off as it means youll have to push piston back to get wheel in again.