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  1. #1
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    Upside down again... :)

    Well a bit off topic - but the idea about Upside Down seems to be back again in the commercial market.

    Wonder if there's any Maverick tech in it?

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  2. #2
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    Saw that in MBA. Pretty interesting. The add said it was light. I wonder how light? I'm also curious about the hub interface.

  3. #3
    Elitest thrill junkie
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    As a single crown, the SUC was much worse than the DUC. The DUC used bulged uppers with a welded crown to overcome some of the inherent issues with twisting that upside down forks are subject to. Although even for the DUC a lighter right-side-up design could have been more efficient in terms of strength to weight, it at least had the benefit of a 2nd crown and increased bushing overlap, something the SUC can't get.

    The new RS1, being made out of carbon fiber, just might have the stiffness to make a single crown design work without twisting. It also might be logistically easier to make than a right-side-up carbon fork, due to the fact that it's hard to weave a carbon structure around small complex parts, like dropouts and fork arches, even though if you *could* make the right side up fork it would still be a little lighter for a given stiffness.

    Will be interesting to see, I can't say I want the RS1 at all, but chassis wise it might just make the inverted single crown a viable configuration finally, vs. all the other failed attempts, SUC, Shiver SC, Dorado SC, Halson Inversion, Mtn Cycle Suspenders, etc...
    "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

    You're turning black metallic.

  4. #4
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    All I have to say is that my SUC has out lasted all of my riding buddies forks. The fox's were the first to fail. There seems to be an issue with lack of lubrication near the seals with the "right side up" forks.

    Failed vs not really noticeable twisting... I would prefer to keep riding.

  5. #5
    Elitest thrill junkie
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    Quote Originally Posted by MrCookie View Post
    There seems to be an issue with lack of lubrication near the seals with the "right side up" forks.
    No, just fox. When they came out they didn't use a proper oil seal like RS and Marzocchi had been using for years. The proper seals are oil seals held in by a snap-ring. The more pressure that is exerted on the seal, the harder it seals. This is why marzocchi was able to use oil level to fine tune progression on their forks for so many years, as the seals could simply deal with the intense pressure just fine. Fox has always been an example of poor lubrication, with the minimal oil bath used in the newer cartridge forks "drying up" after a short amount of time, causing the bushings to chew into the stanchions. Fox has had to resort to the "kashima" coating and new seals due to how poorly the previous setup worked. If you seal it harder to keep the oil in and bad stuff out, it increases the stiction significantly and there's no real constant oil bath to keep everything smooth. The "kashima" helps in most of these respects, but the underlying problem is that fox lubrication has always been weak. As someone who has used suspension forks for 18 years, this has nothing to do with right side up vs. upside down. It has mostly to do with poor fox design. They want to sell forks. This means the have to make them light. They've decided to make some sacrifices to do so. The latest debacle is the "evolution" series, where they've reversed their policy of putting great dampers in even the low-end forks (like the old vanilla R). Now the low end forks get a pumping-rod design like old cheap marzocchis, early 2000s RSs and 1970s motocross forks. They've slid this in largely unnoticed due to the reputation they have for their dampers. They make some great products, no doubt, but they have never really had good seals and the lubrication system on their semi-bath forks has always been pathetic.

    Course, there's always the possible issue of blowing a seal on an inverted fork, which is basically a 50/50 chance you are going to wipe out your brake rotor.

    My old Monster T had one of the best setups of any fork as far as lubrication and seals. Slotted bushings allowed oil to circulate on the legs and up to the bushings to a much greater effect than other forks, and while one set of bushings was "fixed" in the lowers, the 2nd set was set into the stanchions and slid with the stanchions, making for a "dynamic" bushing (which has been copied in some inverted forks in an attempt to increase rigidity). This lubrication coupled with the oil seals (not the things you see on the fork lowers, those are just the dust wipers) made for a pretty amazing chassis. Too bad it was so heavy and equipped with poor/crude damping. Thankfully we've come a long way, but semi-bath forks is still one of those areas where the manufacturers are always walking a fine line between light weight and a fork that simply self destructs.
    "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

    You're turning black metallic.

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