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  1. #1
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    Free stroke - Shimano please explain!!!

    After a recent bike build I decided to go the Shimano XTM785 brakes over Avid because I was told that the 'free stroke' adjuster was equivalent to Avid's contact point adjustment.

    After stuffing around with these brakes for hours I still cannot figure out what the 'free stroke' adjuster does or how it works.

    Shimano has basic information on what it does but no information on how it works or how to use it!

    I've read bike forums, searched the whole of the interwebs and travelled to every corner of the globe and still cannot figure out how these work (okay I exaggerate, but I did got to France last year and saw a MTB or two).

    Can someone who understands this black art please explain it to the rest of us? Heck, even if the legend at Shimano who designed the unit could write a brief explanation that would be really cool.

  2. #2
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    It does basically nothing, and it's a well known fact.
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  3. #3
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    It's supposed to work in a similar fashion to the Avid PCP system. The adjuster changes the point in the lever stroke that the piston in the MC starts pushing fluid to the caliper. Turn it to the + side and the fluid moves earlier in the stoke, pads move sooner, etc. and you get less "free stroke". Turn it to the - side and you get the opposite effect.

    The big difference, as Cil noted, is the Avid system works, Shimano's does not.

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  4. #4
    g3h6o3
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    I'd really love to see the internals of Shimano's free stroke. What I experience on my XTRs is that the free stroke changes the "slack" there is at the lever when pushing it away from the bar (You know the slack that should help prevent damage in case you crash).

    The lever doesn't move, and the feeling when pulling it remains the same. It made me wonder if that was what the free stroke was supposed to adjust... For the 770, the manual seems to indicate this is the case as their picture show a fixed pad contact point. The XTR manual has the same statement and picture.
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  5. #5
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    From what I am reading here it basically controls the modulation of the lever, more pull or less pull. I should have my set tomorrow/following day and will test this all out.
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  6. #6
    g3h6o3
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    Quote Originally Posted by Mr Pink57 View Post
    From what I am reading here it basically controls the modulation of the lever, more pull or less pull. I should have my set tomorrow/following day and will test this all out.
    No need to test it, it won't affect lever pull.
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  7. #7
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    Yeah, it doesnt effect lever pull. As already pointed out, it also doesnt work. I have it on the 810 Saints and the 785 XT's and its the same for both.

    This being said, I love both sets of brakes. But in order to change the amount of free stroke in the systems (especially the Saints) you really need to pull the caliper, give the lever a squeeze or two, and replace it. This pushes the pistons out closer to the pads. The downside is potential pad drag. On my Saints I have given up caring about this, and focus on the pull of the lever and the feel of the brake. Since its on a DH bike it doesnt make much difference.

    On the XT's I havent had to do this yet, and my lever pull has remained very good. It should be noted however that the bike the XT's are on sees probably less than half the use of my DH bike.

    Also, I prefer the lever pull to be very short compared to what it seems most people like. The Saints I got after selling a set of Codes that I hated because no matter what the lever had to be pulled to the bar basically for it to contact.

  8. #8
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    Thanks guys. This all confirms my thoughts. It's still very disappointing though for a company as big as Shimano to include a 'feature' that's basically useless. It's also frustrating as it was the one feature I wanted in my new brake set up. Hmmm may have to revisit the Avids.

  9. #9
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    Quote Originally Posted by AlsTrance View Post
    Thanks guys. This all confirms my thoughts. It's still very disappointing though for a company as big as Shimano to include a 'feature' that's basically useless. It's also frustrating as it was the one feature I wanted in my new brake set up. Hmmm may have to revisit the Avids.

    I do feel your pain about a "feature" not actually working, BUT give the XT's some time. Ive had and tried many Avid brakes and have not liked a single one of them. Even with the feature essentially missing teh SHimano's are still great brakes.

  10. #10
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    That is unfortunate on the free stroke. I do hope mine have some solid modulation I like to get a lot of pull on the lever, my XTR levers (v brake) pull just about to the bar.
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  11. #11
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    Quote Originally Posted by Mr Pink57 View Post
    That is unfortunate on the free stroke. I do hope mine have some solid modulation I like to get a lot of pull on the lever, my XTR levers (v brake) pull just about to the bar.
    Isnt that also a feature of reach adjustment?

  12. #12
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    Quote Originally Posted by 006_007 View Post
    Isnt that also a feature of reach adjustment?
    Not really. The reach adjustment simply moves the lever closer or further from the bar in its static position. So, while if its moved further away, it will also be further from the bar when the lever is fully engaged, you need the longer finger(s) to be able to effectively reach it.

    The free stroke adjusters are SUPPOSED to change the amount of lever pull required to go from static to fully depressed, regardless of the lever position.

  13. #13
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    Perhaps something has changed since 2012?

    https://youtu.be/D0uSTtDWbI8

  14. #14
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    Quote Originally Posted by AlsTrance View Post
    Hmmm may have to revisit the Avids.
    For me personally, I will never return to Avids. Even a non-functioning Shimano component eclipse my best days with Avids.
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  15. #15
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    nice post 702biff. im gonna try that on mine.


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  16. #16
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    Free stroke adjustment controls how far the lever piston must travel before it closes off the port between the reservoir and the cylinder and starts pressurizing the brake line. The screw moves the piston further away or closer to the port. Screwing it in moves it closer so less travel is needed. Lever position is different from this.
    Do the math.

  17. #17
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    My XT8000 brakes came with this free stroke screw all the way in. The problem is that the front lever has much less free stroke than the back brake lever. I want to reduce the free stroke in the back lever to match the front but I'm having no success. Thoughts?

    I just bled the brakes and got some air bubbles out but the free stroke remains unchanged.

  18. #18
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    If it's bottomed out then you have to adjust the fronts so they match the rears. Free stroke moves the lever so it will need reset it to the original height after you get the fee right. You could also move the rear brake level further from the bar to have a similar bite point. I played around with both methods to get them to engage at the same point.
    https://www.youtube.com/watch?v=D0uSTtDWbI8

  19. #19
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    Observing how the pads moved, my free stroke seems to be ok. The problem is that the pads have a longer space to travel before contacting the rotor. I pulled the wheel out and pumped them a bit and now they sit closer.

  20. #20
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    After one ride they are backed out again and I have to pull the lever almost to the bar to get contact. What should I do?

  21. #21
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    I think people don't realize that when you back out the freestroke screw on a Shimano brake, the lever moves away from the bar. When adjust the reach back to where the lever was, then you have more freestroke. There is less range available with Shimano versus other brakes but it does work. Thing is, most people want less freestroke like me so the screw gets left in all the way.

  22. #22
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    The spring that hold helps retract the pads can be too strong or not strong enough. I alway measure mine and make sure that they are even front to back. You can also set the pad spacing by bending the spring. I like a little extra clearance so I usually increase the spring spacing by 3ish mm.

  23. #23
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    The spring is way too weak to retract the pistons. Its function is to hold the pads against the pistons to prevent them from rattling. Some systems use magnets in the pistons for this purpose.

    Free stroke adjustment does not change the distance the pads retract from the rotor. It affects only how far the lever moves before the piston closes off the transfer port to the reservoir.
    Do the math.

  24. #24
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    Quote Originally Posted by someoldfart View Post
    I think people don't realize that when you back out the freestroke screw on a Shimano brake, the lever moves away from the bar. When adjust the reach back to where the lever was, then you have more freestroke. There is less range available with Shimano versus other brakes but it does work. Thing is, most people want less freestroke like me so the screw gets left in all the way.
    Quote Originally Posted by Lone Rager View Post
    Free stroke adjustment does not change the distance the pads retract from the rotor. It affects only how far the lever moves before the piston closes off the transfer port to the reservoir.
    I can't believe how many people (and Bike Websites) say that Shimano's Free Stroke adjustment doesn't work. I have run Shimano brakes since 1999 and all of the ones that had Free Stroke adj worked. As others have posted, it is not a "pad contact adjustment". Just watch the video that is linked above.
    To say that the Free Stroke adjustment does not work, by people who do not understand how it works or what exactly it's supposed to do, is not fair to Shimano.
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