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  1. #1
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    Tuning a Tower Pro

    Hi all,

    I've got a Tower Pro 120 mm, with QR15 and tapered steerer. I've been riding it for some months without thinking too much on adjustments. I had it mounted on a new bike, and I had to get used to many different things..

    I weigh around 155 lbs, so I started inflating it at 60 psi. I felt it much soft, so I added 10 extra psi after few weeks. I mainly rode it with this setting, but now and then I noticed some dive when braking, so I rose air pressure to 180 psi. It felt good on the trail, but I wanted to follow a more rigorous process to try and find the best tuning.

    I've read a lot lately. The topic on clydesdales by TrailMaker has been very inspirational, and I'm re-reading the topic on abs+ tuning by mullen119. As @mullen119 underlines, the most important aspect in the fork's tuning is choosing the right spring.

    I don't want to be under- or oversprung, and yesterday I did several test runs, inflating the Tower Pro's air spring at different air pressures. I started at 60 psi, and then I repeated the same trail at 70, 80, and 90 psi.

    EDIT--Absolute+ LSC set to MAX-4. Rebound damping half way through--

    The main part of the test was a steep descent with several big rough obstacles--rock gardens, drops, roots...

    At 60 psi the ride was harsh at times on big hits (! likely because I have only 50 mm of travel left, because of huge brake dive?), and brake dive noticeable. Small bump compliance was excellent though.

    At 90 psi it felt bumpy and again harsh on big hits. I didn't exploit full travel, but only 80 mm.

    The best feeling was accomplished with 70 and 80 psi. Small bump compliance was better with 70. With 80 I felt more control. I used 110 and 100 mm of travel respectively. On the trail my choice was 70.

    I shot some videos of the descent, to have something more objective than just riding impressions, and see how the fork responded with different pressures. Surprisingly, when I watch the videos I feel the better response is with 80 psi. With 70 it seems the fork is constantly too compressed when I brake (it's steep and I brake way too much!)

    Here's the test video for the fork with 70 psi of air:



    What do you think? I'm interested in your opinion, cause I don't have much experience in what I should actually expect, and the exact interpretation of terms like over and under sprung is not crystal clear to me. It's like the first times you taste wine--what is supposed to be good wine and what bad?

    I believe you shouldn't waste an awful amount of travel just for brake dive. But is the dive in the above vid too much indeed?

    I'll link the video for the 80 psi test in a following post.
    Last edited by solitone; 04-29-2013 at 11:54 PM.

  2. #2
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    Here's the test ride with 80 psi of pressure:


    On youtube you can find also the other two tests with 60 and 90 psi:
    My videos on YouTube

    With 60 I believe the fork is way too soft, as it's always compressed.

    On the other hand, with 90 it seems too hard, as I don't hit full travel. And this trail is one of the toughest I usually ride, so I think I should use almost all travel available.

  3. #3
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    I weigh 190lb and spent some time on a Tower Pro. The fork came w/ a Firm coil and when the air spring pressure was set for proper sag the fork literally used all its travel jumping off a curb I was running max air spring pressure). After talking to a Manitou tech I was advised to try an x-firm spring even though sag was correct w/ the firm. I will mention according to the tech the coil spring is only used for sag & initial fork movement. This MAR's coil spring is in place to remove initial stichion an air spring fork would suffer from. So I installed an X-firm - lost sag and had the same super linear travel gobbler. I came to the conclusion after trying to add oil above the air piston and running multiple pressures / ABS adjustments this was not a fork for my riding style. I do have a Tower Expert w/ ACT that feels great. I will add in your situation I consider brake dive a phenomenon that can be lessened by adding LSC from the ABS damper adjustment. If your fork is riding too far into its travel that is an air spring issue.

  4. #4
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    I forgot to mention I ran those tests with abs+ set to MAX-4 (4 clicks from fully closed). So LSC is already pretty damped.

    You're correct in suggesting that increasing LSC damping would be effective for riding that specific trail. It is steep and pretty smooth but in some very rough sections with drops, rocks, and big roots.

    Nevertheless, for the time being I want to focus on the right spring rate without being influenced by compression damping effects, so I kept LSC half way through.

    BTW, I also set rebound damping half way.

    Do you think the fork uses too much travel with 80 psi as well?

  5. #5
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    Quote Originally Posted by solitone View Post
    I forgot to mention I ran those tests with abs+ set to MAX-4 (4 clicks from fully closed). So LSC is already pretty damped.

    You're correct in suggesting that increasing LSC damping would be effective for riding that specific trail. It is steep and pretty smooth but in some very rough sections with drops, rocks, and big roots.

    Nevertheless, for the time being I want to focus on the right spring rate without being influenced by compression damping effects, so I kept LSC half way through.

    BTW, I also set rebound damping half way.

    Do you think the fork uses too much travel with 80 psi as well?
    As I mentioned MAR's uses the coil spring to set the sag point and eliminate the initial breakaway stichion. The main air spring is supposed to handle the majority of the support. I'd purchase an x-firm coil & see if the performance changes in a positive direction. I couldn't live w/ the Pro's air spring characteristics but am quite glad the ACT was available for the Tower Expert.

  6. #6
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    Quote Originally Posted by solitone View Post
    I forgot to mention I ran those tests with abs+ set to MAX-4 (4 clicks from fully closed). So LSC is already pretty damped.

    You're correct in suggesting that increasing LSC damping would be effective for riding that specific trail. It is steep and pretty smooth but in some very rough sections with drops, rocks, and big roots.

    Nevertheless, for the time being I want to focus on the right spring rate without being influenced by compression damping effects, so I kept LSC half way through.

    BTW, I also set rebound damping half way.

    Do you think the fork uses too much travel with 80 psi as well?
    Are you keeping rebound the same at all three pressure settings?
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    Yes, I wanted to change just one setting a time, in order to not have too factors in.

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    After looking at the videos, I have a few different opinions.

    Your rebound is set too slow. Even at 80psi, the fork seems a little slow in returning. Your spring rate has a direct effect on your rebound setting, so you should change it with the pressure changes. The rebound seems very slow at 60psi and a little slow at 70psi. I would suggest trying it 3/4 open

    It looks in the video to have pretty good small bump compliance, even at 80psi. I am wondering if your expectations for small bump sensitivity are too high for a short travel fork.


    Judging from the video, I would try this setup: 85-90psi in the air chamber for more support through the mid stroke(preventing dive) 5 clicks open on the compression to help with small bump sensitivity, rebound 3/4 open to help feel more active(this will also help small bump sensitivity) Take another video and post it

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    Thanks @mullen119, your suggestions are always much helpful!

    I'll try them tomorrow, I hope it won't rain again

    I agree small bump compliance is very good also at 80 psi. I just noted that at 60 it was unbelievable--the fork completely absorbed small roots and they effectively disappeared. Only at 90 psi it felt a bit bumpy.

    You're perfectly right about rebound. 3/4 open is what I usually use. I set it to 1/2 just for those tests, cos I thought it was a more neutral position to begin with.

    5-clicks open means MAX-5 (MAX is lockout, MAX-1 is 1 click from lockout, ..., MAX-8 is LSC completely open), doesn't it?
    Last edited by solitone; 04-30-2013 at 10:28 PM.

  10. #10
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    Do you have the firm or medium spring?
    If 60 psi makes small bumps feel better, then that means you are using a lot of the air spring for small hits. You might want to go with one step softer spring and raise the air pressure a little bit to reduce the brake dive.

    I wouldn't worry about using too much travel unless you are bottoming out. In that case, add a touch more air, and some more oil on top of the air piston.

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    Yes I have a firm. But sag seems right. And bumps, even small ones, are absorbed after sag (>20% of travel), hence both coil and air springs contribute. This means small bump compliance is influenced by air pressure as well, doesn't it?

    I fear if I reduce coil spring rate I'd worsen mid stroke support, even with higher air pressures. Am I wrong?

  12. #12
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    Tuning a Tower Pro

    Quote Originally Posted by solitone View Post
    Here's the test ride with 80 psi of pressure:


    On youtube you can find also the other two tests with 60 and 90 psi:
    My videos on YouTube

    With 60 I believe the fork is way too soft, as it's always compressed.

    On the other hand, with 90 it seems too hard, as I don't hit full travel. And this trail is one of the toughest I usually ride, so I think I should use almost all travel available.
    Here is a good guide on tuning the Tower
    http://www.jonesparkchronicles.com/ManitouTowerPro.html
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  13. #13
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    Quote Originally Posted by solitone View Post
    I fear if I reduce coil spring rate I'd worsen mid stroke support, even with higher air pressures. Am I wrong?
    In theory, you are wrong. If you look at Shiggy's link, the spring curve starts out kind of linear and then flattens out as the air piston starts moving and the spring and air are acting at the same time. This flattening out is the lack of mid stroke support you are complaining about. If you go with a softer spring and higher air pressure, then the start of the curve is less steep, but since you use more air, the middle of the curve is more steep so you get more mid stroke support.

    Try this: Pump up your shock to the usual pressure, and leave the shock pump hooked up. Sit on the bike so that the fork sags. If the air pressure increases, that means that the air piston is already moving just from the sag. If this is the case, then that also means that you can keep the same sag if you go with a softer spring and use more air pressure. Then the air piston will take over during a later part of the stroke.

  14. #14
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    Assuming that you set the same final pressure to prevent bottom out on big hits...

    Then the difference between running a softer spring vs firmer spring is that:

    The spring (force) curve for the firm spring rises steeply at first, then flattens out, then rises again to the final value.

    The spring curve for the soft spring is more linear is that it rises more steadily towards the final value.

    From here, I leave the interpretation of mid-stroke support to you and the other more experienced suspension tuners.

    For the firm spring, it takes more force to reach mid stroke, but add a tiny bit more force and the fork compresses a lot.

    For the soft spring, it takes less force to reach mid stroke, but you can add a lot more force and the fork will only compress a little bit more.

    Which one counts as mid stroke support?

  15. #15
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    Today i tried the same trail with mullen119's suggested settings.

    LSC set to MAX-5, and rebound to 3/4 open.

    Here's the result with 80 psi:


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    And here with 85 psi:



    I tested it also with 90 psi, but unfortunately my camera stopped working, so no video for that.

    Anyway, I liked 90 psi the less. But I don't trust impressions so much--you know, taste needs to be trained!

    What do you think of the two videos? I felt both 80 and 85 good. Perhaps I preferred 85. It was as if the fork had infinite travel. It never felt harsh, even on rough hits. And I had no complaints as for small bump compliance.

    BTW, is rebound still a bit slow?

    With both settings, although I had LSC 1 click more open than in my previous tests, there was no bobbing when riding uphill (on saddle), even on paved roads.

    With 80 psi I measured 15 mm of sag and 113 mm of used travel. With 85, 11 mm of sag and 111 mm of travel. With 90, 11 mm of sag and 100 of travel.

    Sag measurements don't appear to be very consistent, I don't rely on them too much. They are on the low side, though. I'll try and measure sag again, and see if results are similar.

  17. #17
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    Both videos lookedbetter. 85psi looked the best. Much less diving and stayed up in its travel much better. Still looked to have pretty good small bump compliance too. Rebound looked good at 85psi and just a tad slow at 80psi. Your sag numbers or pretty low, Make sure you are checking with the compression fully open, But if it feels good, dont worry too much about it.

  18. #18
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    Thanks for your taking the time and watch the videos!

    Yes, I checked sag with LSC fully open. Anyhow, different measurements give different results, to me it's difficult to have a precise measure of static sag. I'll try again though.

    And I wonder how significant it is, considering I don't ride with abs+ fully open..

    BTW, I measured sag in a "neutral" position, standing up with moderate weight on the front wheel. Do you measure it on saddle instead? In that case i'd have even smaller figures.

    --EDIT--
    I compared the 2 videos shot at 80 psi, the 1st with rebound damping set to MAX-1/2, the second to MAX-3/4. Rebound is tremendously better in the 2nd vid. It seems the fork stays higher on its travel, although pressure's the same and compression damping is even 1 click more open.
    Last edited by solitone; 05-02-2013 at 02:52 PM.

  19. #19
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    Quote Originally Posted by beanbag View Post
    In theory, you are wrong. If you look at Shiggy's link, the spring curve starts out kind of linear and then flattens out as the air piston starts moving and the spring and air are acting at the same time. This flattening out is the lack of mid stroke support you are complaining about. If you go with a softer spring and higher air pressure, then the start of the curve is less steep, but since you use more air, the middle of the curve is more steep so you get more mid stroke support.
    Yes, I think a Medium spring is an option I should explore. I'd be curious to see spring curves to compare spring rate for different coil springs and air pressure, though. I asked for them to Manitou's CS, and the guy who supported me was very kind, but unfortunately he had no spring curves to send me. I'll try again..

    I just fear that it'd be difficult to get a proper mid-stroke rate with a softer coil spring. The two springs (coil and air) are in series, so both springs influence rate in the mid range. In the following picture, I drawed in green the spring curve for a Firm spring. For the same air pressure, the spring curve with a Medium spring would be the red curve. The softer spring lessens the rate in the mid range.

    Tuning a Tower Pro-spring-curves-examples.jpg

    It's true that increasing air pressure would increase rate, but I wonder at which point the higher air spring rate would compensate the lower coil spring rate. It may well be that I end up with a softer MARS spring in the mid range, and then the spring spikes (dashed red line in the picture above), as TrailMaker describes in the guide Shiggy linked.

    Difficult to say without real spring curves or experimentation!

  20. #20
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    I don't know where you got those curves from, but they're probably wrong. The reason is that both the firm and medium spring will be fully compressed at full stroke, so the final force for those two curves has to be the same. And if the firm spring is so firm that it is not fully compressed, then the green curve is still wrong because the slope at 120mm should be less than at 0mm.

    Keep in mind that the air piston has an area of about 1.1 sq inch, so if you are running 80psi, then the piston is not even moving until you put 88 lbs on it. On my medium spring for a 100mm minute pro, it takes maybe about 100 lbs to fully compress that spring. If I were running the medium spring at your pressures, then my spring would have been pretty much compressed in the midstroke range and mostly relying on the air.

    Like I said earlier, leave the pump attached to your air chamber and see how much the fork compresses until the air piston starts moving. I think you should be running a softer spring to get more sag anyways.

  21. #21
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    Quote Originally Posted by beanbag View Post
    The reason is that both the firm and medium spring will be fully compressed at full stroke, so the final force for those two curves has to be the same.
    Have you tested the spring rate or is this speculation? I assume Manitou doesn't publish the spring rates. I've got a Tower Pro on the way so I'm reading up on the Mars setup.

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    ^^

    No no, it was just speculation. As I said, I'd like to have real spring curves, but unfortunately I don't have any for Firm and Medium coil springs.

    As far as I know, the only available spring curves currently available are the following, which refer to the XX-Firm (AKA Clydesdale) coil, though. These curves where provided to TrailMaker by Manitou's chief engineer Ed Kwaterski, and he published them in the interesting doc referenced by shiggy.

    Tuning a Tower Pro-manitoutowerproclydecoilgraph.jpg

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    Ya, I read TrailMaker's article. Although the absolute numbers in that chart don't apply to softer springs, it gives a very clear picture of what part of the curve the different variables affect. As far as spring rate goes, it's not that hard to measure. I like having curves to look at, but I doubt I will go down that road with this fork unless I have issues.

    If you haven't already done so, I strongly urge you to experiment with the low speed rebound setting. It seems to be the most widely overlooked aspect of suspension setup and can make or break the action.

    I'm curious to hear if anyone has played with revalving the high speed rebound.

  24. #24
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    Quote Originally Posted by ktm520 View Post
    Ya, I read TrailMaker's article. Although the absolute numbers in that chart don't apply to softer springs, it gives a very clear picture of what part of the curve the different variables affect.
    Yes, but the thing those graphs don't tell you is where (i.e. at which point in travel) the curve for softer coil + higher pressure becomes greater than that for stronger coil + lower pressure.

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    Quote Originally Posted by beanbag View Post
    I don't know where you got those curves from, but they're probably wrong. The reason is that both the firm and medium spring will be fully compressed at full stroke, so the final force for those two curves has to be the same.
    You're perfectly right. Those curves where just sketches I drawed, and I was wrong. As you said, final force has to be the same with both coils.

    On my medium spring for a 100mm minute pro, it takes maybe about 100 lbs to fully compress that spring.
    How do you know that? Do you know what force is needed to fully compress a firm spring?

    I'll do the test you suggested, as well as measuring sag again--hopefully getting more precise measurements.

    Cheers

  26. #26
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    I measured my spring by holding a flat plate over the top and then putting most of my weight into it.

    That chart you have shows the spring curves for your firm coil. I dunno about your coil, but mine for a 100mm fork can compress by less than 2" before it bottoms out (e.g. the blue plastic push rod hits the metal compression rod).
    Next time you have your spring out, you can see how much yours compresses and get the force value from the chart.

    There is something weird about the manitou chart in that the 90 psi black curve starts to diverge from the spring at below 50 lbs. That is odd.

  27. #27
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    Quote Originally Posted by solitone View Post
    Yes, but the thing those graphs don't tell you is where (i.e. at which point in travel) the curve for softer coil + higher pressure becomes greater than that for stronger coil + lower pressure.
    All you need is to measure the height / volume of your air chamber, and then you can calculate these curves out yourself.

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    Quote Originally Posted by beanbag View Post
    There is something weird about the manitou chart in that the 90 psi black curve starts to diverge from the spring at below 50 lbs. That is odd.
    Yes, because the air piston should begin move at about 100 lbs

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    Quote Originally Posted by beanbag View Post
    Try this: Pump up your shock to the usual pressure, and leave the shock pump hooked up. Sit on the bike so that the fork sags. If the air pressure increases, that means that the air piston is already moving just from the sag. If this is the case, then that also means that you can keep the same sag if you go with a softer spring and use more air pressure. Then the air piston will take over during a later part of the stroke.
    I've measured how much the fork needs to compress so that the air piston starts moving. As usual, it's difficult to have accurate measurements, next time I'd better ask a friend to help me.

    Here are the results. I also noted sag figures where available, but I need to measure sag again to have more accuracy:

    • 70 psi: air piston moves at 8 mm (sag 28 mm)
    • 80 psi: air piston moves at 11 mm (sag 12 mm)
    • 85 psi: air piston moves at 15 mm (sag 11 mm)
    • 90 psi: air piston moves at 17 mm (sag 11 mm)
    • 100 psi: sag 12 mm


    As you see, only with 70
    and (perhaps) 80 psi the piston moves from the sag. With 85+ psi the piston moves later in travel, therefore sag depends only on the coil spring rate. This explains why sag doesn't change increasing air pressure from 85 to 90 psi.
    Last edited by solitone; 05-04-2013 at 08:26 AM.

  30. #30
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    I did the same test on my fork and the piston also moves before I think it is supposed to. I think there must be a trapped air space somewhere, or some kind of rubber bumper or o-ring under the piston that allows it to move around. I never had the air piston out so I wouldn't know.

    In any case, I made some plots for MY fork. I guessed on the spring rates. Also, the final force came out to be a little too low so I am missing various air pockets trapped in other parts of the fork.



    In any case, I used to have a medium spring but now I run a soft spring. It ends up giving a smoother and more linear curve.

  31. #31
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    Quote Originally Posted by beanbag View Post
    I did the same test on my fork and the piston also moves before I think it is supposed to.
    Do you refer to my piston, or to what is shown on Manitou's plots?

    I don't know whether or not my piston moves before it is supposed to.

    --EDIT--

    BTW, why the force of the MARS spring at full travel (100 mm) is lower then the force of the air spring alone, in your plots?

    We said the coil spring is fully compressed at that travel, so the force of the MARS spring should only depend on the air spring.
    Last edited by solitone; 05-03-2013 at 01:06 PM.

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    u add the dotted plots horizontally to get the total travel

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    I'm afraid I don't get it. In your graph, the red and blue continuous lines (MARS spring) peak to 170 lbs at 4 inch displacement (100 mm). In contrast, the green dotted line (air spring) is much higher at 4 inches, although it's not shown.

  34. #34
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    you don't actually end up compressing the air chamber 4 inches. it compresses 2 inches and the spring compresses 2 inches and thus the fork compresses 4 inches. You are supposed to read this graph like it is sideways, i.e. you pick a force value first and then read off the displacements.

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    OK.

    I measured the air piston movement again, and I confirm that 80 psi are enough to reach the point where the piston moves at a displacement equal to sag. More than 80 psi, and the piston moves at a displacement greater than sag.

    So, for pressures >= 80 psi, sag is given only by the coil spring, and it is 11-12 mm--too little, because the firm coil is too hard for my weight.

  36. #36
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    A lot of great info in this thread on how to tune the Mars spring system. Either beanbag or Solitone should make a guide with the tips and tricks to make sure you have the correct coil spring for your weight and what not. The spring system is complex enough that a lot of people have problems setting it up, and a guide on here would help a lot of people.

  37. #37
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    Sure! As soon as I complete my tests I'll wrap up all information in a how to guide.

    I've just ordered a Medium Ride Kit and soon I'll be able to try the new setup.

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    some more videos

    This evening i shot some more videos.

    Here is the test with 90 psi, that last time I didn't manage to record:


  39. #39
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    new vid 85 psi

    And, as a comparison, here a new recording with 85 psi, that last time was really poor quality:



    All other settings are the same: firm coil, LSC damping MAX-5, HSC stock trail shim stack, rebound damping MAX-3/4.

    Please comment!

  40. #40
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    85 psi on a different path

    And a longer descent on another path, which should allow to check the fork's behaviour on different conditions (fork inflated with 85 psi of air).



    Here there are no steep sections, but the surface is generally rougher, with many boulders.

    As in previous vids, there's a pretty amount of mud because of the heavy showers we have been experiencing in the last weeks here. So the camera lens isn't always clean.. Sorry for that!

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    If you really want to tune your Tower, you can get the tuning kit which will allow you to do some pretty specific types of adjustments. It ain't cheap, but if you are a tinkerer and want to dial it in, that will pretty much handle anything you desire.

    I still have to replace my spring to the firm, but I confess - I a little nervous on attacking that yet. I want to arch the videos a few more times.

  42. #42
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    Quote Originally Posted by beanbag View Post
    All you need is to measure the height / volume of your air chamber, and then you can calculate these curves out yourself.
    Is it really that easy? Is it a simple cylinder?

    Do I need to just measure my air chamber's height to get its total volume, and subtract the volume of oil (should be 5 cc in my case) to know the volume of air?

    But then what gas compression model should I use, to get pressure increase from volume decrease (i.e. travel)? Boyle's law? It wouldn't be appropriate, though, 'cause on high speed compressions air temperature can't be assumed as constant.
    Last edited by solitone; 05-09-2013 at 03:42 AM.

  43. #43
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    Quote Originally Posted by iCollector View Post
    If you really want to tune your Tower, you can get the tuning kit which will allow you to do some pretty specific types of adjustments. It ain't cheap, but if you are a tinkerer and want to dial it in, that will pretty much handle anything you desire.
    Yes, you're right, I'm aware of that possibility, and it's an exciting option I already explored with my old(er) Minute Expert.

    For the time being, though, my focus is finding the correct spring rate for my weight/riding style. Afterwards, I'll try and tune also the shim stack.

  44. #44
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    Quote Originally Posted by solitone View Post
    Is it really that easy? Is it a simple cylinder?

    Do I need to just measure my air chamber's height to get its total volume, and subtract the volume of oil (should be 15 cc in my case) to know the volume of air?

    But then what gas compression model should I use, to get pressure increase from volume decrease (i.e. travel)? Boyle's law? It wouldn't be appropriate, though, 'cause on high speed compressions air temperature can't be assumed as constant.
    Yes, Yes, and ideal gas law. P1*V1=P2*V2

    You don't have to buy the 200$ tuning kit to revalve the ABS. Download the tuning guide from mullen119's thread and go buy shims from your favorite shim supplier. Depending on what you want to do, it should only require buying a few shims @ 2$ a piece.

  45. #45
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    Oh right, you are supposed to use adiabatic gas compression. That would account for a few extra pounds at full compression. Also don't forget psi gauge vs absolute pressure.

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    Yes, in fact I already have most of needed shims--Manitou CS posted them to me for free !! when I was tuning my Minute Expert.

    I'll start with Boyle's.

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    I've been following this thread with great interest and it's got me wondering, is there a noticeable difference in performance and settings once a Tower Pro is "broken in"? The reason I ask is that I've only got about 8 hours on mine and the settings and air pressure I'm using to get the desired results are *way* different than the OP's. Should I get the recommend 20 hours in before I make any significant changes like ride kit, etc.?
    I'm 183lbs. ready to ride, using a 100mm QR15 Tower Pro with a 2011 Spec Camber 29. I'm working on setting it up for maximum plushness on the small to medium hits (knowing that I'm trading that for a fair amount of mushiness when pedaling standing) because of my old, arthritic wrists. So far I'm getting the best results at 70 psi, rebound at 1/2, compression damping at 1 click from full open (!), though I'm not getting as much sag as I'd expected. At my weight, I wouldn't think I'd need a medium spring though.
    Overall, my settings sound pretty light compared to what's being discussed in this thread, so I'm wondering about the break in period. My main riding area is pretty tame with the biggest drops around 1', but I've yet to notice any bottoming out.
    We don't stop playing because we grow old; we grow old because we stop playing.

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    I didn't notice any brake-in on mine, even though Manitou say it takes several hours to break it in.

    As for your light settings, I also would be using lighter settings if my rides didn't include very steep descents, with rough sections.

    Consider that Donn, a guy at 29eronline, weighs like me, but is using a Soft spring with 70 psi, as he commented to the following video of his, so a much lighter setting as well:



    My current setting though is what I prefer for heavy trail/all-mountain riding. I'll see what changes are needed when I install the new Medium spring.

    It's strange you don't get the desired sag. With 70 psi and the stock firm spring, I have a 25% sag (measured in attack position, though--probably it's a 15-20% on saddle, but I'm lighter than you).

  49. #49
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    Quote Originally Posted by ric426 View Post
    Overall, my settings sound pretty light compared to what's being discussed in this thread, so I'm wondering about the break in period. My main riding area is pretty tame with the biggest drops around 1', but I've yet to notice any bottoming out.
    I have a Minute Pro which is pretty much the same fork in a 26" wheel version. There is a break in period where the fork gets smoother and stiction goes down or disappears, and that's about it. The settings I used didn't change. Like solitone, I have a lot of super steep and rough sections on my local trails, plus I like to ride aggressively so I run much heavier settings than usual. I'm 150 lbs and run 105psi, 5 clicks from full closed on compression, and 1/8 of a turn from full open on rebound.

  50. #50
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    FYI I redid my plot with adiabatic gas compression and got about 40 more lbs at full compression. It seems closer to real-world values. So I suggest you do it that way.

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