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  1. #1
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    Anyone felt they needed 120mm for rear shock on the M429C?

    Just curious - my shock and fork are at Fox getting a rebuild so I took my a Trek Rumblefish Elite out yesterday. The bike has 120mm front and back.

    I have to say that I was a different rider. More aggressive. Even my riding buddy noticed I was tackling stuff much more aggressively and I was only 1 second short of a PR going down a rocky section and I haven't ridden this bike for almost 6 months. The bike was just more predictable and I was having a blast.

    FOX has come back with their plan and apparently the damper in the front is shot and there is some kind of air / oil issue in the back. How this translated in the actual ride characteristics was there was no real difference in CTD modes and a feeling of too much bouncing / bucking in technical sections (slow or fast). At high speeds downhill (over 20mph) the bike just skips over rocks rather than complying with the terrain. Then of course on climbs there was no lockout on the front or rear shocks. Rebound and psi were set to 25 percent sag and about half way out for both front and rear shocks. Compared to bikes in store with same shocks, mine felt totally different. Bikes in store had clear difference between CTD and seemed to want to utilize the entire stroke where mine would fight back from using the entire stroke. Tire pressure dialed to 25f / 30r psi on both bikes.

    So - when the suspension is working properly did you ever feel you needed more travel in the rear shock? If not is it possible to swap out a 100mm shock for a 120 on the M429C? General consensus is the DW Link seems to add an apparent 1 inch of travel but just looking for experiences with this bike when the suspension is working as designed. Thanks.

  2. #2
    Pivotal figure
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    If you change the shock to a 120mm stroke the tire is going to hit the seat tube under compression OR the rocker will hit it at full extension.
    Desert Sunset Calls/Upward, Pain, Perseverance/Welcome Solitude

  3. #3
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    Maybe your shock needs to be custom tuned for you by Push.

  4. #4
    OriginalDonk
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    I've ridden both bikes in question and recognize that ride preferences are subjective. For me the Mach 429c was the better bike by a wide margin climbing, descending, and riding swoopy mixed terrain. The DW outperformed the ABP of the Trek across the board and the geo of the Pivot leant itself toward more aggressive line choices on the descents. There's a reason why a lot of guys run the 429c in enduro racing.

    My question to OP is how long has it been since you serviced your suspension. If the fork damper is shot and the rear shock is cavitated it sounds like you may be well beyond the service interval of both and are experiencing suboptimal suspension performance. The fact that bikes in the shop felt significantly different also suggests the same.

    Looks like you live in San Diego where there's a fair amount of chunk but the 429c should be able to handle most of that terrain with 100mm rear and 120mm front unless you're really lettin' it rip. I say give it another comparison with the recently serviced suspension and let us know how it goes.

  5. #5
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    Anyone felt they needed 120mm for rear shock on the M429C?

    Thanks OD - I think you are spot on. I will post up next week once shocks come back and I get my bike back.

  6. #6
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    My DWlink bike had same issue until shock rebuilds.

  7. #7
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    I dont think the 429 needs +20mm, but it should could use another +30MM,
    Mach 529 is what I have been wanting for quite a while..that way there is a clear separation from CC/trail bike to more trail/AM. BMC looks like they nailed one, on paper

    I have ridden the M429C a bunch of times and its great but as a heavier rider that rides a variety of terrain I just need more travel for my one and only bike.

    I have a tallboy LTC and 135mm is pretty capable, but i really miss pivots DW suspension..

  8. #8
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    Anyone felt they needed 120mm for rear shock on the M429C?

    Just revisiting this - got shocks back from Fox and they installed all 2015 internals. The difference in ride is night and day. Hit all sorts of PRs on my last ride. Now have plush when I want it and lockout when I want it.

  9. #9
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    Nice move.

  10. #10
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    Well, the saga continues.

    I got the fork back from Fox and after just a few rides it a) made a strange creaking noise when I turned the wheel and b) felt as if the bushings were not right (front fork had play in it when rocking back and forth with front brake applied). Brought it back to the LBS (they love me now lol) and the lead technician also noticed some other strange stuff. Back it went to FOX.

    In the interim, I had a wallet tantrum because I was sick of waiting for 2+ weeks to not ride my bike and just outright bought a new fork (2014 CTD Fox FIT Float model - figured I could just swap forks whenever one needed it's 50 hour service interval) and had the LBS put fork #2 on my bike. All was good, except the seals were obviously dry. My first ride, and I was like, "Ok, NOW what's wrong?" All I could hear was "squeak squeak squeak every time my fork hit even the smallest rock."

    Hanging bike upside down and dripping float fluid into the seals seemed to fix THAT issue and the fork now works as advertised. I guess it is "normal" to have to essentially service a new product with forks?

    Anyway back to fork #1 - it came back from FOX and I haven't ridden on it yet, but they have installed not only the 2015 damper, but the 7 position trail switch as well. So I essentially have a brand new fork for my troubles. Manually depressing the fork seems to indicate that the bushings are fine, and the action is very smooth.

    I suppose the moral of the story is if you have a late '13 or even '14 Pivot with FOX Float CTD Factory series, you MAY (emphasis mine) have a bike that isn't riding the way it should - The difference with a properly functioning suspension is MASSIVE - even uphills are faster due to the better low frequency compliance, and of course the downhills are now as they should be and are much more confidence inspiring.

    If your climb mode in the front fork isn't almost completely locked out, then you probably have the problem I had. Go to your LBS and check out how the NEW FOX forks feel and compare them to yours. That is what I did and now I finally have my Pivot riding the way it should be.

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