Hope Brake Problem...

[jimo746]

Hope Mono M4 front brake, noticed a drop of brake fluid on the lever the other day, now when I pump the lever I get a drop of fluid coming out and dripping off the lever :shock:

What could be wrong?

I did bleed the brakes about 2 months ago, but all was fine until last week when I first noticed the fluid leak.

I assume some rubbery part/master cylinder is on it's way out? Suggestions/cures with links to what I need to replace would be appreciated.
I've not played about with dic brakes a great deal in the past, but the Hope ones seems pretty simple to work on.

 

[02gf74]

from your desciption it sounds like a seal has gone.

and is is DISC brake not DIC brake.

 

[jimo746]

hmmm... I hadn't noticed that typo

 

[jimo746]

I've just ordered a Mono M4 complete seal kit, guess I can keep the caliper seals for future use.

Now, the brass barrels on the levers.... mine seem to have a fair bit of play in them, can they be replaced easily?

 

[greenstiles]

hi is it on the back/ front of the lever near where it joins the master cylinder housing ? or by the hose joint ?.............just trying to work out if it's from the lever piston or it it's run along from somewhere else, check the resivoir top is tight enough (don't over tighten), or hasn't just weaped a bit of fluid from the cap............. any loss of lever feel ?

if you need to change the lever piston, you will need a good set of circlip plyers.

 

[jimo746]

Thanks for the reply, the "leak" seems to be coming from where the lever blade goes into the brake lever body, so I'm assuming that some rubbery bit inside there is failing.

No obvious loss of power or excessive lever movement yet.

I will double-check all those areas you mentioned tomorrow though, I may have missed something, and it would be a quick and cheap fix!

Fortunately I recently bought some circlip pliers for working on suspension forks etc, so they will come in handy again

 

[ChrisR]

Fortunately Hope brakes can be fully rebuilt so no matter what part you should be able to get it

 

[greenstiles]

ok sound like alever piston replace..........when you take it all out just lay it out 'as it came out' some you can see how stuff goes in ' in sequence'..........

 

[suburbanreuben]

You should be able to find a How-to vid, either on youtube or Hope's own site technical section.

 

[jimo746]

So I finally got around to replacing the seals in the master cylinder/lever this evening, all went well, and the leak has now gone.

However, despite bleeding the brakes (twice) they don't feel all that sharp, there seems to be a bit too much lever travel for my liking.
In comparison to my rear brake (Hope Mono Mini) the front seems to have less power and require more lever pull to work well.

Everything seems ok though, but I removed the brake pads and pulled the front brake lever and noticed that one or other of the larger pistons would move first, and move further than the other pistons.
Are all pistons supposed to move an equal amount, and in unison??

Is there some way to set up the brake so that it requires less lever pull to operate it? My own personal prefernce is for more of an "On/Off" setup with only a small amount of lever pull required to get full braking force.

:?