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Poll: PM or IS, which is better?

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Thread: IS v PM

  1. #1
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    IS v PM

    As simple as that. Preferences? Don't care?

    The reason I ask is that there is a shift back to PM, and I don't really understand the reason for it. I stripped the threads on the only PM fork I have and had to red loctite the bottom bolt to keep the caliper from shifting. Seems like a dumb idea to me, but that's just my humble opinion.

  2. #2
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    I always notice with post mount brakes, when you go to tighten the caliper bolts, the caliper will twist a little, no matter how hard you are squeezing the lever. I see this especially with the avid brakes, but basically with all post mount brakes. This leads to the uneven pad wear I see quite often with said brakes.

    IS is more definite IMO. You have to "shim" the caliper, but the shims are definite and it's impossible for the caliper to shift or twist. It does necessitate a good facing sometimes though.
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  3. #3
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    Quote Originally Posted by Jayem
    I always notice with post mount brakes, when you go to tighten the caliper bolts, the caliper will twist a little, no matter how hard you are squeezing the lever.
    You have to tighten them up in little increments or they will move. More like you would do on a two-bolts stem. Just like back in the days of vees. I hated vees just for that and I'm so happy to have ditched them.

    I also prefer PM... but is only a personal preference. Actually I've been lucky with both types. And both have advantages and disadvantages.

    Only Manitou had used PM's before... and judging by the track record of Manitou, I'm positive no other PM fork manufacturer would get stripped threads.

    IS seems very easy to manufacture too, it's all in the casting. No need a second machining step for the threads and facing.
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  4. #4
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    If PM is so good then how come the rear on frames doesnt come in it?
    Actually if PM is stronger then it is sometimes better to be stronger then such but since IS has been working well with no issues it should just stay anyways.
    Sure shimming the brakes sometimes takes some time but once setup I havent have any problems with it shifting on me or whatnot.

    I can see the reasoning behind going to PM is like stripping the threads requires a whole new lower section of the fork where as with IS stripping you can replace the caliper for alot less.
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  5. #5
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    I prefer IS, but that's purely based on the fact that two of my friends have had PM thread holes strip out on Manitou forks. That's not too hard to do in Mg, I know from personal experience with my Boxxer pinch bolts, although admittedly they were not threaded in very deep.

    The disadvantage of IS is that it's probably easier to bend the tabs.

  6. #6
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    IS seems very easy to manufacture too, it's all in the casting. No need a second machining step for the threads and facing.[/QUOTE]

    No steps?
    I can't believe how many IS forks I have had to face this year (never mind the rear ends) because the tabs are misaligned - costs time and money

    With the PM forks - I have seen some forks where the customer has stripped out the threads due to overtightening the bolts rendering the brake unsafe (very expensive mistake - not Manitou's fault)

    Now that Marz is on the PM bandwagon, I think the other fork manufacturer's will switch over to this standard within the next few years.
    Which ever way it goes I'm easy

  7. #7
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    Quote Originally Posted by Warp
    You have to tighten them up in little increments or they will move.
    Not in my experience. I've installed many dozens of sets.
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  8. #8
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    Quote Originally Posted by Jayem
    Not in my experience. I've installed many dozens of sets.
    Me too... take your time with each bolt.
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  9. #9
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    Quote Originally Posted by cort
    IS seems very easy to manufacture too, it's all in the casting. No need a second machining step for the threads and facing.[/QUOTE]

    No steps?
    Not on my Magura at least.

    Nah, seriously, fork manufacturers have omitted this step, you're correct on that. But also many brakes have been installed without facing succesfully.

    Let's assume you need to machine the tabs... it's a one step machining. Just threading and facing makes two steps for PM... not to mention you have to shape the casting for the lowers as with IS.
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  10. #10
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    I have major beef with the post mount. Aside from the threads stripping then requiring helicoil or replacement, I recently transfered my setup from an IS mount fork to a post mount 66SL and I can't get the caliper perfectly aligned. With IS, your brake tabs are either straight, or they need to be faced; once you do that, it is smooth sailing. With PM, as pointed out above, the damn thing twists a tiny bit, at the very least, when you tighten the bolts. Now, my ultra silent, up to this point, Louise FRs are loud. Not during hard braking, but when modulating, they squeal. A totally new phenomenon to me. I don't understand why Marzocchi did that to the consumer, but they totally eFFed the ultra reliable brake setup of their previous forks.

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  11. #11
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    Post mount is better in so many ways. It's stiffer, stronger, much easier to align (hey no shims) and there aren't 6 different mongrel variants.

    Sure muppets end up stripping out the threads (too much torque on bolts that're too short), but helicoils were invented for such people.

    I'd like a bike with post mount on the back, but it doesn't fit with most common manufacturing methods. Only those with a whole cast dropout and mount could do it easily.
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  12. #12
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    IS Mount

    It's the only mount I've ever used, and it works just fine. It would be nice if the industry could just standardize to one or the other. Just seems kinda silly that something as simple as a means by which you attach the calipers isn't consistant across manufacturers.

    Perhaps someone can give us some history on the two mounting types and how they came about. The name "International Standard" would indicate to me that at some point it was indeed the standard, or at least intended to be the standard.

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  13. #13
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    I really wonder why we are seeing this PM trend. One reason I wanted to do this poll was to see if the consumers believed PM to be better. I mean, I really can't see another reason to ditch IS. Sure, the IS mount is weaker, but how many times have you, personally, ripped off a caliper? Why not use a different bolt material (or slightly larger diameter bolts)? What I'm saying is that I think there are other options out there, but the fork companies don't want to confuse things even more. That was the reason for the development of IS in the first place, and I think that companies are a little worried about introducing what they believe to be the best option simply because it doesn't conform.

  14. #14
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    Quote Originally Posted by Dougal
    Post mount is better in so many ways. It's stiffer, stronger, much easier to align (hey no shims) and there aren't 6 different mongrel variants.

    Sure muppets end up stripping out the threads (too much torque on bolts that're too short), but helicoils were invented for such people.

    I'd like a bike with post mount on the back, but it doesn't fit with most common manufacturing methods. Only those with a whole cast dropout and mount could do it easily.
    First PM for me after 6 years of IS using the same Avid mechanicals. The swap to a Manitou Elite fork with PM was easy. The twisting when tightening the bolts was a minor issue. The bolts were long and snug, it would have been really tough to strip them. I was worried the post might split open from the snug threading, so backed them out a few times to "chase" the threads, and it was not a problem.

    Avids have a floating mount so they mount easy to either (with adaptors for IS).

    Cars and motorcycles use larger "IS" type mounts, maybe it's the better way. PM seems good too. The floating mounts of Avid and Hayes make either type easy to align, so I have no preference using floating mounts, although IS seems more thread stripping idiot proof.

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    Last edited by derby; 06-14-2006 at 08:24 AM.

  15. #15
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    Quote Originally Posted by Guyechka
    I really wonder why we are seeing this PM trend. One reason I wanted to do this poll was to see if the consumers believed PM to be better. I mean, I really can't see another reason to ditch IS. Sure, the IS mount is weaker, but how many times have you, personally, ripped off a caliper? Why not use a different bolt material (or slightly larger diameter bolts)? What I'm saying is that I think there are other options out there, but the fork companies don't want to confuse things even more. That was the reason for the development of IS in the first place, and I think that companies are a little worried about introducing what they believe to be the best option simply because it doesn't conform.
    You reflect exaclty what I think...

    Don't quote me, but I seem to recall the IS referred to the radial dimensions around the front axle... not exactly axial dimensions which is where most differences arise.

    And true, if strenght and stiffness of the IS mounts would be a real issue, manufacturers could just make them thicker, use larger diameter bolts and holes, etc.

    PM would be sweet if they had already the helicoils installed (I've never stripped one, though)... and you can't make sure the surfaces are properly aligned from factory. Well, you can but it ain't as easy as with IS.

    Seriously, I don't think any of the two would be better than the other. I'd like for any of the two would die forever and we would have only one standard.

    Actually, bike manufacturers would have to sit down along with the ISO organization and standarize lots of things. As the situation is now, it's really little cost effective for everyone.
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    It doesn't really matter to me what I have, but I don't like using the bracket to make my PM Juicies work on my IS fork... it adds grams. Grams are the enemy. I just wish stuff was more compatible or available with either mounting option... I don't think the Avids are available in an IS configuration (correct??). The brakes were easy to mount though without any facing required.

  17. #17
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    Quote Originally Posted by Rich A.
    It doesn't really matter to me what I have, but I don't like using the bracket to make my PM Juicies work on my IS fork... it adds grams. Grams are the enemy. I just wish stuff was more compatible or available with either mounting option... I don't think the Avids are available in an IS configuration (correct??). The brakes were easy to mount though without any facing required.
    I have Avid mechs on my XC bike. The fork is a Manitou Black Elite, which means the front brake just uses Avid's funky washer system to bolt on directly. Now this is just fine, and I like the fact that, with their system, you don't have to worry about perfect facing. However, the rear brake is what has me puzzled. To use Avid on the rear you must use their PM to IS adaptor. Isn't that a little redundant? Now that does, unnecessarily add grams. Also, don't you think having a double bolt connection (caliper to adaptor and adaptor to tabs) adds play? Of course, I would much rather have it in the rear than the front, if I must have it at all.

  18. #18
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    Time is money and it's quicker for bike companies to assemble PM and not have to worry about alignment. Same thing with Juicy's- very good brake, but so are a lot of others, but they are really quick to fit and with idiot proof alignment they save time.

    I've never had a postmount fork, they've always been IS. I've always faced the tabs and spent time shimming the caliper well. It takes time, but once done it's done for good and if you're using an IS caliper then it it also lighter than using an adaptor. For me the only advantage to PM is for large scale bike building.

    The only downside to IS - apart from time to set up correctly- is the possibility of ovalising the bolt holes. I noticed this once on a set of my forks, it was only slight but nontheless it was there. The bolts were tight and had been threadlocked BTW. Magura have addressed this problem in the past by fitting steel reinforcements to the tab holes, which i thought sounded like a good idea although i've never owned any of their forks before.

    I have been happy with IS forks in the past and would rather buy forks that used this system in the future, although dedicated IS calipers are getting fewer and fewer.
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  19. #19
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    Quote Originally Posted by Call_me_Clyde
    Perhaps someone can give us some history on the two mounting types and how they came about. The name "International Standard" would indicate to me that at some point it was indeed the standard, or at least intended to be the standard.

    Bob
    It all happened just before the 2000 model year.
    Everyone sat around a table and tried to agree on a standard, everyone but hayes and manitou did.

    The hayes bolt pattern and hub spacing was adopted, but the "International Stanard" had several variations so it
    didn't really work as a standard.

    The IS mounts are 10mm different in radius front and back. So you can't use the same calipers and discs front and back.
    Then the hub mount was referenced from the hub centre, but the fork mount was referenced from the dropout face so the 20mm fork brake mount wasn't compatible with the QR fork brake mount.

    Then RS screwed the pooch further by keeping a mongrel mount on the boxxers and not using the correct horizontal spacing on the 20mm psylos.

    It got worse with some companies using IS+20 mounts on forks where they couldn't easily fit an IS mount.


    Basically the IS mount (even if it was cast properly) was offered in soo many different guises that making different calipers fit different forks and frames was just a PITA.

    The post mount doesn't change, front or back, 20mm or QR, it just doesn't matter. They're all in exactly the same place and fit the same caliper/rotor combo.

    Check out the front brake mounts on a Yamaha R1 some day.
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  20. #20
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    I'd rather buy a helicoil than a new caliper (especially now that there are one piece castings). Post Mount has been good to me for 5 years on 3 different forks.

    Link to a Yamaha R1 for PM action: https://www.sportrider.com/bikes/200...-r1-d-05-1.jpg .
    Last edited by pan; 06-15-2006 at 01:08 PM.

  21. #21
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    Quote Originally Posted by pan
    I'd rather buy a helicoil than a new caliper (especially now that there are one piece castings). Post Mount has been good to me for 5 years on 3 different forks.
    .
    Well, the castings are much softer than what a caliper is made out of, so stripping a caliper hole is not really much of a reality, but stripping the soft magnesium or aluminum of lower castings is much more likely.
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  22. #22
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    Quote Originally Posted by pan
    I'd rather buy a helicoil than a new caliper (especially now that there are one piece castings). Post Mount has been good to me for 5 years on 3 different forks.

    Link to a Yamaha R1 for PM action: https://www.sportrider.com/bikes/200...-r1-d-05-1.jpg .
    Is it just me or the rear brake looks like IS-type?
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    Quote Originally Posted by Warp
    Is it just me or the rear brake looks like IS-type?
    Shouldn't we compare products with the same intended use?

    This one looks like to be used on the dirt... Not that that makes any difference, but makes you wonder why it uses the nasty IS-type arrangement.

    Anybody seriously thinks one of the two is better? I think it's just another way to skin a cat. As with anything, there'll be people who'll prefer coke over pepsi and viceversa.
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    Quote Originally Posted by Jayem
    Well, the castings are much softer than what a caliper is made out of, so stripping a caliper hole is not really much of a reality, but stripping the soft magnesium or aluminum of lower castings is much more likely.
    Actually Jm, most brake calipers are aluminium.
    Given that you can get a greater thread engagement on post mount than you can with IS, it makes it a no brainer really.

    But the only people who strip out threads are either using the wrong bolts or just twisting too hard. Both are symptoms of a very crappy mechanic.
    In over five years and about 6 different postmount forks, I've never stripped one.

    But now with RS and Marzocchi joining manitou with post mounts. The battle has already been won.
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  25. #25
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    Radial post mount future for bicycles

    Quote Originally Posted by Warp
    Shouldn't we compare products with the same intended use?

    This one looks like to be used on the dirt... Not that that makes any difference, but makes you wonder why it uses the nasty IS-type arrangement.

    Anybody seriously thinks one of the two is better? I think it's just another way to skin a cat. As with anything, there'll be people who'll prefer coke over pepsi and viceversa.
    Old tech bikes. Dirt bikes and touring bikes usually change little year to year.

    The sport bike market is most competitive, and each manufacturer must keep up to sell new bikes.

    The new sport bikes all have radial mounted brakes with post mounts now for much easier spacing adjustment for larger race rotors and for less irregular twisting the fork while trail-braking in a corner.

    Now if bicycles would use radial design, post mount would make a clearly better performance difference than the current asymmetrical mounting of either system.

    - ray
    Last edited by derby; 06-16-2006 at 10:07 PM.

  26. #26
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    Quote Originally Posted by Dougal
    Actually Jm, most brake calipers are aluminium..
    Well no kidding, notice I didn't say they were made out of steel.

    What I was saying is that fork lowers are much softer, whether they're made of aluminum or magnesium. It's a much softer allow, and not forged or CNCed from a block like calipers are.

    This makes them much different.

    Were you confused?
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  27. #27
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    my bike has IS mounts, therefore i use IS brakes. mainly for weight-savings, but the brakeset is light-weight also (formula b4sl+) and i got them for a killer price. if my frame had post-mount, i would've probably gotten post-mount brakes.

  28. #28
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    This is easy - IS requires shims and PM doesn't. My friend has brakes that mount directly to his IS mounts, and every time he takes one of his wheels off and puts it back on again there's some rubbing. I'll gladly live with the IS-to-PM adaptors on my Hayes brakes and be able to easily readjust them whenever I need to. I would rather have a PM fork though. Fox, are you listening?

  29. #29
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    The simple fact that both standards lived so long shows that they are pretty equivalent in terms of pros and cons.
    When I switched from Manipoo to Marzocchi I kept my post mount brakes and bought an adapter IS to PM. This works great as I'm not worried about stripping threads (adapters ae cheap) and it's easy to align.
    Standardization could help reducing costs and in the end pricing for end users....
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    Quote Originally Posted by Zen_Turtle
    Standardization could help reducing costs and in the end pricing for end users....
    I think the biggest benefit will be reduced confusion.
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  31. #31
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    Quote Originally Posted by Dougal
    I think the biggest benefit will be reduced confusion.
    Yeah, same as with BB threads, pull ratios on derrailleurs, pull and swing of front derrailleurs, head tube sizes, pedal cleats, etc.

    All manufacturers will claim an advantage, some people will be on favor of this or that system (and defend it to death)... but things would be simpler and better for the consumer. It just seems that that doesn't push much sales, otherwise, we'll have much more things standarized.
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    Quote Originally Posted by Warp
    Yeah, same as with BB threads, pull ratios on derrailleurs, pull and swing of front derrailleurs, head tube sizes, pedal cleats, etc.

    All manufacturers will claim an advantage, some people will be on favor of this or that system (and defend it to death)... but things would be simpler and better for the consumer. It just seems that that doesn't push much sales, otherwise, we'll have much more things standarized.
    But then that would seem to be a vote in favor of IS. I'm not disagreeing with you that I would like to see some standardization. It's just that IS was supposed to take care of that in the first place, but it obviously didn't work. I mean, no one is going to hold a gun to the fork manufacturers' heads and tell them they must conform. On the other hand, most companies did go ahead and use the IS system for a decade--Manitou is the one major holdout I can think of--and all is good for the customers, who can now buy forks and brakes without worrying that they won't match. Then all of a sudden the industry switches gears and more companies are using PM. The only two reasons for this that I could think of were strength and customer preference--which could also have something to do with strength. The poll shows that there is a nearly even split. I guess that suggests the fork companies are going to waver between the two for another decade?
    Last edited by Guyechka; 06-17-2006 at 04:59 PM.

  33. #33
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    Quote Originally Posted by Guyechka
    most companies did go ahead and use the IS system for a decade--Manitou is the one major holdout I can think of--and all is good for the customers, who can now buy forks and brakes without worrying that they won't match. Then all of a sudden the industry switches gears and more companies are using PM. The only two reasons for this that I could think of were strength and customer preference--which could also have something to do with strength.
    Strength is only one advantage, personally the ease of adjustment is what does it for me. I don't carry shims on a ride so if I replace a wheel and it sits differently, I can deal with it in seconds with postmounts.
    Interestingly weight savings has ranked quite high for the proponents of IS.

    I think it's fantastic that other fork makers have finally seen the light. Not only with postmount but 1.5" steerers seem to be getting the nod too.

    On the other hand, no other companies have rushed out to make a single sided fork.
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  34. #34
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    I don't buy into the "ease of adjustment" argument. Shims are definite, but the caliper twists when you tighten the bolts with a post-mount, and most of the ones that I see wear down their pads at strange angles.
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  35. #35
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    Quote Originally Posted by Dougal
    I don't carry shims on a ride so if I replace a wheel....
    I don't carry replacement wheels on rides.
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  36. #36
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    Quote Originally Posted by Jayem
    I don't carry replacement wheels on rides.
    You don't read very well either.

    If you have a wheel with a threaded axle, it'll sit in a different amount every time the axle is rotated. Often a remove and replace will make the disc rub.

    Not my fault you can't tighten bolts properly.
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  37. #37
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    Quote Originally Posted by Dougal
    If you have a wheel with a threaded axle, it'll sit in a different amount every time the axle is rotated. Often a remove and replace will make the disc rub.
    If that happens, simply push the pads back with a tyre lever, and push the brake lever a few times... done.

    Note that to produce a significant disalignment you have to have a badly spaced hub and some badly spaced fork's dropouts, maybe sticky pistons too. From there the self-adjustment on the pads can take the differences.

    I personally don't like to mess with the two allen bolts on the caliper with PM's. Avids and their spherical washers take a little bit more time, but that's the price to pay for the ability to run a non-faced tab (either PM or IS)

    As I said, both systems have advantages/disadvantages.... they're just like pepsi and coke.
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  38. #38
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    Quote Originally Posted by derby
    Cars and motorcycles use larger "IS" type mounts, maybe it's the better way.
    Not anymore. All high performance car and motorcycle brakes use radial (post) mounting, that's where the idea came from for MTB's.
    Last edited by Rivet; 06-17-2006 at 10:52 PM.
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  39. #39
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    Quote Originally Posted by Warp
    but that's the price to pay for the ability to run a non-faced tab (either PM or IS)
    You've been facing post mounts? What combo made that necessary?
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  40. #40
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    Quote Originally Posted by Guyechka
    ...the only two reasons for this that I could think of were strength and customer preference...
    i would think, for the manufacturers, that the main reason is cost. it costs less to make one caliper for front and rear, post-mount and IS.

  41. #41
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    Quote Originally Posted by Dougal
    You've been facing post mounts? What combo made that necessary?

    Have you ever checked yours?
    I don't think they're all perfectly straight. And that may be why people like JM is seeing weird wearing patterns on PM's. Of course, it maybe incorrect installation too, but chances are you can get out of plane surfaces also. You KNOW it can happen. Now, if you've got one that's defective or not, that's another tale. I have never had to face IS tabs for instance, but I can not neglect the fact that many people has had to.
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  42. #42
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    Quote Originally Posted by Dougal
    You don't read very well either.

    If you have a wheel with a threaded axle, it'll sit in a different amount every time the axle is rotated. Often a remove and replace will make the disc rub.
    Maybe you should find some better equipment? Over 7 years of riding disc brakes (mostly IS mounts) and that problem has never been an issue for me, nor have I seen anyone have that issue. I'm not even sure what you mean by "threaded axle", since I've extensively used 20mm axles and standard QR axles, and still not had any issues that you're talking about.
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  43. #43
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    To add another point to this discussion...

    There have been a few occassions where the caliper/rotor were mis-aligned due to other circumstances other than uneven tabs.

    This year alone, I have had to replace three caliper adaptors (two from Hayes = 8" one front and one back, and 8" from Avid = front) to correct the alignment.
    All three adaptors, were indeed IS, but I don't think the problem would have been adverted had it been a PM adaptor either.

    Side note: Caliper and adaptor were bubble wrapped and zip-tied to the bike during the shipping process so I don't believe the problem was cause here

    So, what I am trying to say is, companies such as; Hayes, Avid etc should pay particularly close attention to their caliper adaptors as they do with their own brakes.

    Hopefully this was just a localized problem, with a little bad luck on our shop's part
    Last edited by cort; 06-18-2006 at 10:21 PM.

  44. #44
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    Quote Originally Posted by Warp
    Have you ever checked yours?
    I don't think they're all perfectly straight. And that may be why people like JM is seeing weird wearing patterns on PM's. Of course, it maybe incorrect installation too, but chances are you can get out of plane surfaces also. You KNOW it can happen. Now, if you've got one that's defective or not, that's another tale. I have never had to face IS tabs for instance, but I can not neglect the fact that many people has had to.
    Yes I have checked mine.

    The calipers have always bolted up straight over the rotor. But the swivelling pistons of hydro brakes take care of small misalignments anyway.

    I primarily use hayes. Haven't had any problems with pads not wearing flat either.
    What brakes did you find that on? By any chance ones with pistons pushing on the centre of the pads (i.e. hope mini)?

    I fail to see how certain fork castings can be "defective" and need faced while others of exactly the same casting can be fine.
    Sure with IS mounts covered in thick paint variation will occur, but manitous post mount faces aren't painted.

    Call me a sceptic, but I've seen many bad mechanics blame the machinery they're working on for their own ineptitude.
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  45. #45
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    Quote Originally Posted by Jayem
    Maybe you should find some better equipment? Over 7 years of riding disc brakes (mostly IS mounts) and that problem has never been an issue for me, nor have I seen anyone have that issue. I'm not even sure what you mean by "threaded axle", since I've extensively used 20mm axles and standard QR axles, and still not had any issues that you're talking about.
    So you've never seen a "threaded axle".
    I guess you've never seen a shimano deore disc hub then.
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  46. #46
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    Quote Originally Posted by Dougal
    Yes I have checked mine.

    The calipers have always bolted up straight over the rotor. But the swivelling pistons of hydro brakes take care of small misalignments anyway.
    This has been my experience with both IS and PM. Except for the rear brake, where there could be wild variations in manufacturing of the tabs.

    Quote Originally Posted by Dougal
    I primarily use hayes. Haven't had any problems with pads not wearing flat either.
    What brakes did you find that on? By any chance ones with pistons pushing on the centre of the pads (i.e. hope mini)?
    Shimanos, for example. They separate pads with a spring... maybe that would help to uneven wear. My Magura Julies wear very flat too, just small wedgings, but nothing to make the brake problematic or noisy.... except when I got the brakes, that the previous owner was an arse and th brakes had sticky pistons, incorrectly MOUNTED pads, severe misalignment, etc.

    Quote Originally Posted by Dougal
    I fail to see how certain fork castings can be "defective" and need faced while others of exactly the same casting can be fine.
    Sure with IS mounts covered in thick paint variation will occur, but manitous post mount faces aren't painted.

    Small variations in manufacturing like shrinkage rate of the alloy, cooling tempreatures, tolerances on the casting itself. machining tolerances, etc. I admit that PM is less prone, because of the machining. But you know the mentioned problems above can arise too. Everything (made the same) has certain tolerances and they will not be exactly the same. These are bike components and not parts for the space shuttle, so tolerances may be greater and some works will need a lot of work while others dont.

    Quote Originally Posted by Dougal
    Call me a sceptic, but I've seen many bad mechanics blame the machinery they're working on for their own ineptitude.
    Oh, that's a very true statement. Maybe the most sensitive in this whole thread.
    But I think you are missing my point. I've been saying that IS is no superior to PM or viceversa. Some people will prefer PM, some others IS. It's a freaking can of worms. Both systems work very well, both systems can be screwed up by a dumb mechanic too.

    Look, if suddenly IS (or PM) would disappear, I'd be happy all over. Even if I had to buy a new caliper... whatever manufacturers decide to use, please use just one "standard".
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  47. #47
    dcb
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    How come it's so expensive to fix a stripped PM? Can't you just go get a 7mm bolt and a tap and fix it?

  48. #48
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    Quote Originally Posted by dcb
    How come it's so expensive to fix a stripped PM? Can't you just go get a 7mm bolt and a tap and fix it?
    You could do that, but it's a half arsed fix.
    Non standard parts suck.
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  49. #49
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    Well I'll let you know how it works out in the long run because I tapped my Nixon last weekend after stripping the threads in the lower mount. Honestly it never occured to me to do anything different than fixing it the way I did. In many years of working on my cars, motorcycles and bikes I've stripped a thread here and there. I've never had a problem yet with tapping some new threads and I hope I don't this time. But if I do, it will give me an excuse to replace the Nixon with a Marz AM SL which I've contemplated quite a few times anyway.

  50. #50
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    Quote Originally Posted by dcb
    Well I'll let you know how it works out in the long run because I tapped my Nixon last weekend after stripping the threads in the lower mount. Honestly it never occured to me to do anything different than fixing it the way I did. In many years of working on my cars, motorcycles and bikes I've stripped a thread here and there. I've never had a problem yet with tapping some new threads and I hope I don't this time. But if I do, it will give me an excuse to replace the Nixon with a Marz AM SL which I've contemplated quite a few times anyway.
    You lie! dougal said no one ever strips out those mounts!

    Kinda like how airplanes are made out of aluminum. I had to really reinforce the point to my buddy who has a cessna that he can't go using a powerdrill with a phillips driver to put in screws because they're all going into relatively soft aluminum. You have to be carefull, and I've never seen any mechanics really torque the hell out of those screws, because the material they are going into is "soft". He had just rounded out a cowling screw when I informed him of this. He's always looking for "shortcuts" though, not necessarily the best idea with a plane.

    Threads in soft magnesium react similer, except with an allen or torque head you can really put a lot more torque into it...
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

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