hope tech3 lever throw-bleeding

Home Forum Bike Forum hope tech3 lever throw-bleeding

Viewing 29 posts - 1 through 29 (of 29 total)
  • hope tech3 lever throw-bleeding
  • freeriding
    Member

    Hallo! I have the tech 3 v4 brakes, they are amazing! I have 3 questions:

    –how do i reduce the lever throw? I have the pad contact fully in, but would like a little less throw. I have avid rotors, think hope rotors may be a bit fatter?

    –i read that except for the classic bleed procedure, there is a reverse one, from the caliper to the lever body. How is it performed? Has it any advantages over the classic one?

    –for more raw power (since i experience no fade with the organic pads), should i go organic or sintered? Any brand that has better pads than the stock hope?

    Premier Icon nixie
    Subscriber

    Doesn’t the bite point adjustment take care of question one?

    Never used the reverse bleed, no idea why you would, the classic way is quick, simple and works.

    Organic is more power with short life, sintered better wear but less retardation. Choice depends on the weather as much as anything (don’t expect organics to last long in wet winter slop for example), or what your riding. If you like how they were out of the box just get the same pad again. I’ve given on on cheap pads now, just use the hope ones.

    Premier Icon andybrad
    Subscriber

    tech 3 e4 here.

    I find they work ok ish and are constant but the thing that really improves them is working the pistons. It may be worth a try?

    kiksy
    Member

    –how do i reduce the lever throw? I have the pad contact fully in, but would like a little less throw. I have avid rotors, think hope rotors may be a bit fatter?

    I have E4s.

    I spent ages trying to get the amount of throw down, the BPA and reach simply coudln’t get them close enough without having loads of travel before the bite would start. After multiple bleed attempts I read a solution on here that worked for me.

    Wind both the reach and BPA all the way out. Add a brake block that ins’t too thick (or use an old rotor and tape in place.) do a bleed as normal to ensure no air, then screw the cap and seal back onto the lever, but leave the syringe attached to the caliper. You should still have some DOT fluid in the syringe from the bleed. Push the plunger in a few cm’s to force extra fluid into the system then close the caliper nut tight.

    I found using this method it’s possible to get zero “dead” throw. The second time I did it I wound the BPA all the way out, then a few back in again to allow me to have a small amount of dead throw to make them a bit less grabby.

    They now feel similar to my old XT’s,much less vague and I can have the levers where I want without them going to the bar.

    Premier Icon andybrad
    Subscriber

    cool ill try that

    freeriding
    Member

    Add a brake block that ins’t too thick (or use an old rotor……..leave the syringe attached to the caliper).

    –do i need to do this? If i make the bleed the normal way, with the pads on?

    You should still have some DOT fluid in the syringe from the bleed. Push the plunger in a few cm’s to force extra fluid into the system then close the caliper nut tight.

    -so, i will attach a syringe to the caliper? How do you secure the hose of the syringe to the caliper outlet? with a ziptie? (normally you attach just a hose to take the fluid from the lever pushed)

    –Do you mean mm? I guess that i won’t be able to push the plunger for some cm, because there will be no space for so much fluid? Won’t the pistons come out if i do that or won’t the rotor rub in the pads after all?

    kiksy
    Member

    –do i need to do this? If i make the bleed the normal way, with the pads on?

    I guess that would be fine. I tend to just take everything out to avoid contamination.

    -so, i will attach a syringe to the caliper? (normally you attach just a hose to take the fluid from the lever pushed)

    I use the Epic bleed kits: http://www.epicbleedsolutions.com/products/bleed-kits/hope/basic-kit/#t-0

    This comes with a syringe. You attach the syringe to the bleed port, undo the bleed port nut and then pull on the syringe to suck fluid/air out of the system, then keep topping up the lever container with DOT fluid until no more bubbles come out.

    –Do you mean mm? I guess that i won’t be able to push the plunger from some cm, because there will be no space for so much fluid? Won’t the pistons come out if i do that or won’t the rotor rub in the pads after all?

    Yes I guess mm rather than cm, I didn’t force it with any strong pressure, just pushed the plunger a bit, which moved a little. I had a tiny bit of rotor rub on the rear after I did this, but after 10mins of riding this went. The brakes now come on much much sooner as the pads are closer to the disc to start with, but that was the goal.

    freeriding
    Member

    Thank you very much! The syringe is attached to the hose and the hose secured to the port with a zip tie?

    PS. the official way of bleeding does not involve any syringe.

    Premier Icon andybrad
    Subscriber

    that vid is how i do it. Id be concerned about not having any room for the fluid to expand?

    tjagain
    Member

    don’t overfill. As the pads wear the brakes will revert to previous bite point and the seals could blow as they will be permanently distorted.  Lube the pistons and set up the centralisation as hope recommend will get you minimal dead throw

    kiksy
    Member

    don’t overfill. As the pads wear the brakes will revert to previous bite point and the seals could blow as they will be permanently distorted.  Lube the pistons and set up the centralisation as hope recommend will get you minimal dead throw

    I tried re-centering and rebleeding multiple times but still had lots of dead throw (maybe 75%) when I had the levers setup where I like them.

    I have a couple of friends with Hope brakes, with their levers setup how they like them there is little dead throw, however, adjusting their levers to fit me, they were both back to huge amounts of dead throw. Hence why I tried the overfill method as a last resort. The dead throw is so annoying I’m happy to take the risk of damaging seals unless I can find another better solution.

    Premier Icon pedlad
    Subscriber

    I’ve pratted around with all of the above techniques at various times over the years with numerous hopes.  Best method IMHO is to first check the pistons  are all pushing and retracting smoothly – if not do a quick clean and lube of them in situ. I zip tie the good ones so the sticky ones can pump out to match.  Then with a braking block in, do normal hope bleed (don’t bother with the syringe method).

    Line up the calliper centrally on the disk without the pads in and tighten.  Don’t do this with the pads in by squeezing the brakes with loose bolts then nipping them up…as per many a youtube vid……if you think about it this just introduces bias on the calliper’s position, depending on which piston moves quicker on that that pull.

    Then with pads in, centralise the pistons using a screwdriver on the backing plate. If you have a lazier piston, i.e. the disk is getting pushed towards it, push the pads back against the “stronger” piston and give the brake lever a little pump.  This really reduces the lever throw and makes the 2 pads push onto the piston equally, giving more powerful braking.

    After this adjust BPA and lever reach (which also affects bite point feel at the lever) to suit.

    freeriding
    Member

    Line up the calliper centrally on the disk without the pads in and tighten

    How do you do this correctly? If you base on rough eye measurement, then you will certainly be wrong.

    I really don’t get how you centralize the caliper! We are dealing with mm here, so something more precise should come into play.

    Premier Icon pedlad
    Subscriber

    there’s a central line visible on the calliper, much clearer to line up with the disk when pads are out.

    Premier Icon nwmlarge
    Subscriber

    I bleed my HOPE brakes using a shimano bleed block that I sanded down by 0.9mm to give the perfect lever travel.

    I used a vernier to ensure that the bleed block was even throughout, took ages as the bleed block is made of tough plastic.

    I follow the standard bleed procedure with this method.

    Always worth cleaning the pistons from time to time and re-lubing them also to ensure they work well.

    Until I made the thinner bleed block I couldn’t get my old XT’s to the position I wanted either.

    I don’t mess with the lever adjustments.

    Premier Icon Akers
    Subscriber

    Some interesting advice. Bookmarked for later. Cheers.

    Premier Icon howsyourdad1
    Subscriber

    I’ve never been fully happy with my v4s, too much lever through, so I’m very interested in this. Only got dot 4 in da house but will be giving some of these methods a try

    freeriding
    Member

    Do you think i can get less lever throw than this? This is the best i could .
    Is this considered a low lever throw or high?
    I would like a bit less.

    https://streamable.com/fnk2o

    Premier Icon nwmlarge
    Subscriber

    That looks about right to me, i’d prob wind the lever out a bit for me as I have longer fingers.

    kiksy
    Member

    Do you think i can get less lever throw than this?

    I have a little bit less than that, but that’s because I didn’t.like it quite so grabby. Using the overfill method I got less than half what you have in that video with the adjusters wound all the way in.

    freeriding
    Member

    I’m afraid that with the overfill method, there will be a problem in the long run (eg seals), cause the fluid needs space to expand (dot absorbs water). What do you think

    You got less than half of my lever throw in the video? Can you post a video?

    ndthornton
    Member

    Lever throw is not dependant on how much fluid is on the system unless you over fill which i wouldnt recommend as it leaves no room for heat expension. The distance the lever travels before the pads contact the disc is governed by the flexibility of the piston seals. The seals are disigned to move with the piston up to a certain distance and then if it moves further to allow the piston to slip past the seal. This is how auto adjust works for pad wear. If you start with the pistons all the way in and keep pumping the brake you will find the lever travels all the way to the bar and the pistons gradually move out. For most of the travel the piston is moving with the seal…only the last 3rd or so of the stroke does the piston move past the seal. As the piston moves out fluid from the reservoir fills the system up. When the pads finally contact the disc the distance they return is the total streach in the piston seals. Therefor it is this streachiness of the seal that governs lever throw which is decided at design time.

    Keeping seals lubed, replacing every few years and properly aligning the calliper will help.

    kiksy
    Member

    I’m afraid that with the overfill method, there will be a problem in the long run (eg seals), cause the fluid needs space to expand (dot absorbs water). What do you think

    I’m no expert, and so take other opinions over mine, but personally, given the choice of either having to have the lever too far away from the bar , having so much dead throw the lever goes to the bar or overfilling and having the feel I want at the risk of damaging seals, I’ll gamble with the seals.

    As I said earlier, I’ve tried all other methods multiple times, plus brand new rotors. On all my other friends Hopes if I adjust them to suit my hands then they all have the same amount of dead throw (~70%).

    Therefor it is this streachiness of the seal that governs lever throw which is decided at design time.

    This is interesting, thanks for posting such an indepth response. Does this mean I’m kind of stuck with lots of throw without overfilling?

    If anyone else with Hopes can be bothered, I’d be interested in seeing how much throw people have with my setup:

    BPC: All the way in

    Reach: 3 turns from all the way out

    So basically, as close to the bar as possible minus 3 reach.

    @freeriding Here is a video showing how much throw I have at the moment:

    The first few pulls are to the point where I can feel some good resistance, then the big pull is trying to get it to the bar. I’d say my dead throw is about 10mm,maybe a little less.

    Rockhopper
    Member

    They look well spongy, mine are nothing like that.  You’d trap your fingers behind the lever.

    ndthornton
    Member

    This is interesting, thanks for posting such an indepth response. Does this mean I’m kind of stuck with lots of throw without overfilling?

    You might be – if they are Hope V4 brakes. I have those brakes and they do have a reasonable throw on them. the more Pistons you have and the bigger they are the more fluid you need to move in order to shift them. Mine bite just before the bar which is where I like it actually – I find I can grip the bar better under heavy braking.

    I should point out I am no brake expert – just an engineer who wanted to find out how open hydraulic brake systems worked in order to save a set of XTR brakes which were playing up. In this case the lever throw was ridiculous – you actually had to pull the lever twice in quick succession in order for the pads to contact the rotor which meant anticipating when braking was required in advance!!

    I had messed around with bleeding and calliper alignment for ages to no effect. I could find very little information about how mountain bike brake systems work but plenty on car and motorbike brake systems. I was surprised to discover that the elasticity of the piston seals are responsible for returning the pistons to there starting position. I can confirm this is the same with mountain bike brakes as I have taken many callipers apart and there is no other spring in there to accomplish the task.

    After I worked out these seals were the likely cause of the problem I swapped them out and the problem went away. Perhaps my seals had stretched and were causing too much throw?

    kiksy
    Member

    They look well spongy, mine are nothing like that.  You’d trap your fingers behind the lever.

    Interesting. I’ve got these setup now to be easily the least spongy Hopes I’ve used (out of maybe 4 other pairs on friends bikes.)

    I don’t trap my finger as I have the levers set further in on the bar to avoid this.

    How did you get yours setup @Rockhopper ?

    kiksy
    Member

    Mine bite just before the bar which is where I like it actually – I find I can grip the bar better under heavy braking.

    Out of interest how far do you have the lever from the bar? I have the lever pretty close :

    BPC: All the way in

    Reach: 3 turns from all the way out

    Rockhopper
    Member

    I only use one finger for braking, i set them up as per Hope’s instructions, pads out, push pistons right back in, line up caliper by eye, pads back in the squeeze lever.

    I shortened the hose so I bleed them as per most brakes on cars, bikes etc.  Bit of silicone tube, open nipple, squeeze lever, close nipple etc.

    ndthornton
    Member

    Out of interest how far do you have the lever from the bar? I have the lever pretty close :

    Definitely not close – but not miles out as I don’t have huge hands and wouldn’t be able to reach

    Maybe 2.5 inches? I cant be sure really

    I will photograph tonight if you want?

Viewing 29 posts - 1 through 29 (of 29 total)

You must be logged in to reply to this topic.