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  1. #1
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    Finally, an innovative high pivot drivetrain

    https://m.pinkbike.com/news/first-lo...the-trail.html

    Sometimes the biggest innovations are so simple your engineering brain thinks ‘hmmm this shoulda been obvious years ago’.

    The benefits story here is much more than just a way to protect a derailleur from impact damage.

  2. #2
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    Yeah, that's a pretty cool idea.

    I'll be interested to see if they can adapt it to work with non-high pivot bikes. While there are clearly some upsides the high pivot layout, that suspension design isn't universally awesome.

    Regardless, nice to see someone bringing some new ideas to the drivetrain table.

  3. #3
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    pretty smart engineering using exisiting parts, the unstock/extra part is the tensioner and a custom der,

    he is saying its a positive to have a designated tensioner instead of using the Der to tension which causes more drag

    quite a bit to unpack and absorb in that ^^ artical

    I think you need the high pivot to get the chain up out of where buddy has put the der, so it has to be a high pivot design which is i believe the answer to changing chain line issues so its good
    Last edited by XXX-er; 11-12-2021 at 03:54 PM.
    Lee Lau - xxx-er is the laziest Asian canuck I know

  4. #4
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    This is super cool.

  5. #5
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    Am I the only one worried about my monster Dong getting caught in that thing?

  6. #6
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    Quote Originally Posted by Falcon3 View Post
    Am I the only one worried about my monster Dong getting caught in that thing?
    Lots of us are worried about your dong.

  7. #7
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    besides der protection and the things mentioned in the vid I'm wondering if this design would shift better/ more consistantly ?

    it looks like the der is mounted by 2 widely spaced screws for a more positive/ stiffer mount

    instead of hanging down able to move from side to side the der is pulled in the same direction of the chain travel which should make for more positive shifting

    you don't always break a der or hanger mostly you just bend the hanger or der which should not happen in this design so it should shift the same all the time

    I wonder how it is adjusted ??
    Lee Lau - xxx-er is the laziest Asian canuck I know

  8. #8
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    Adjusted, as in adjusting limit screws? It’s like a normal derailleur limit screw adjustment.

    I agree, seems like more positive shifting. But we’ll see.

  9. #9
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    The valve brought out the luddites. Where's the OG derailleur love?

  10. #10
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    Looks interesting, especially for the unsprung weight reduction. More chain wrap on the cogs has obvious upsides, but it also results in slower shifts in the larger cogs while you wait for the chain to come around.

    Doesn't seem like this needs to be a high-pivot, necessarily: put a tensioner right behind your chainring and lop off the cage and you'd have the same effect (though it might still need about half a cog of chain wrap). Getting that tuned in for how much chain to take up versus tension on any given bike seems finicky that way, though.

  11. #11
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    i can't see anything that would slow down the shifting ? If anything the DER would have a more solid ( 2 wide mount screws) mount than a normal DER which hangs out there on a single bolt with a lot of pivot points, the seperation of the chain tensioner from the DER has to be a positive thing

    you couldn't do the design without a high-pivot and fit everything in the space aloted , think of it as a drive train where the design has been rotated 90 degrees counter clockwise around the axle , without a high pivot the top chain would hit the der and the spring loaded tensioner pulley

    besides high pivots are good on FS designs because of a better chain line

    no B tension screw on further reading

    alot to unpak in that artical
    Lee Lau - xxx-er is the laziest Asian canuck I know

  12. #12
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    Derailleurs (rear ones, anyway) take time to complete a shift because the chain has to travel around to the top from wherever the pulley is. Watch sometime and you'll notice that when you shift from 2nd to 1st, for example, the ratio change occurs when that first link that got moved onto the big cog finally gets around to the top. It's not a big deal on recent drivetrains because they've used less chain wrap (by angle/same-ish by tooth count) in the bigger cogs. If you're pedaling really fast it's less noticable, too. But if you wrap around 200 degrees of the biggest cogs you'll notice shifts don't complete until you've done most of another revolution on the cranks.

    I'm sure how much that matters will be personal. I probably notice it more because I'm comparing to a Pinion. Whenever I get on my fatbike I notice the delay.

    I'm not opposed to high pivot, either. But since it's possible to fit a tensioner up close to the chainring it's probably possible to package this a little differently if one was determined not to go high pivot. The rear pulley location is a little constrained, though, like you alluded. Might lose some total range. It's an interesting thought from a perspective of purely unsprung weight.

  13. #13
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    Quote Originally Posted by jono View Post
    I'm not opposed to high pivot, either. But since it's possible to fit a tensioner up close to the chainring it's probably possible to package this a little differently if one was determined not to go high pivot. The rear pulley location is a little constrained, though, like you alluded. Might lose some total range. It's an interesting thought from a perspective of purely unsprung weight.
    The rear pulley isn't really location constrained though, is it? I mean, clearly there's an advantage to having it tucked way up high. But it doesn't look to me like there anything about that design that would prevent the derailleur from being rotated downward into a more traditional position. And even if it was situated like a normal derailleur, it'd still only have the one pulley wheel and would be way more compact and out of the way.

    The main trick with that system appears to be that for the tensioning pulley to have enough travel, it has to be positioned essentially vertically. Which means you have to route the chain up over an idler to keep it out of the way. And once you've committed to dealing with idler fuckery, you might as well go high pivot.

  14. #14
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    Yeah, the derailleur pulley could easily move, although how much might come down to whether the chain can wrap around the bottom instead of the top or if that would be too imprecise/not enough wrap on the pulley. If that's feasible, though, the line from the idler has some freedom before the chain gets too close to the cogs.

    I haven't scribbled it onto a napkin or anything, but I think there's room for the idler to come around quite a bit. I've looked at that for belts and it seems like the downside of the forward/single pulley tensioner is mostly just that the idler has to be designed for the frame specifically. Of course, that's not looking for 10" of change, either.

  15. #15
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    a protected der is suposed to be one of the positive reasons for this design so after buddy tucked it up between the stays why would you want the der hanging down ?

    My point is look at where all the components of a regular system go and then what buddy does in this design is move them each 90 degrees-ish counter clockwise around the axle point is all,

    the chain would even be pulling from slightly further back on the rear cogs but its just going to change where ever the ramps are on the rear cluster allow it so i don't see how that will slow gearchanges down ?

    the idler pulley is suposed to allow lower tension/ less drag than the spring of a der according to the artical which are positive things
    Last edited by XXX-er; 11-15-2021 at 06:41 PM.
    Lee Lau - xxx-er is the laziest Asian canuck I know

  16. #16
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    Yeah, it may be that running less tension is worth a lot more pulley wrap, but we won't notice.

    Figure the time to shift by counting the number of teeth between the der pulley and the top of the cog (where the chain leaves the cog). Figure your chain speed as your crank rpm x chainring size for teeth per minute. Divide those cog teeth by the teeth per minute and that's how many minutes it takes from when you click that shifter far enough to get the chain picked up until the gear ratio actually changes.

    If you double the number of teeth that takes twice as long. Or if you have the chain wrapped 2/3rds of the way around the cog and the cog is 1.5x bigger than your chainring, it's going to take a full rev of the crank to finish the shift.

    The concern about derailleurs would be about 90% less if they had only the one pulley, already tucked up pretty high. Nothing against a little more, but it might be overkill.

  17. #17
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    ^^^ that.

    And I want a protected derailleur on a non high pivot / idler bike. This design seems like it's currently resigned to only occupy the long travel enduro sled segment. Which is fine, but a lot less interesting than a drivetrain that can work on any bike.

  18. #18
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    the chain/ front chain ring/ cogset are all existing stock pieces that you would currently find on an enduro sled with a 1x system

    read the heading " Finally an innovative HIGH PIVOT drivetrain "

    it only works on a high pivot

    there are not twice as many teeth

    a der with 1 pulley are you fucking kidding me ? You are more likley to get a pony for xmas
    Lee Lau - xxx-er is the laziest Asian canuck I know

  19. #19
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    Maybe we should discuss this in the morning. Sometime after coffee, perhaps.

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