Jump to content

New Engagement System


FoxRacer

Recommended Posts

That BB looks like they've cut away a chunk of the BB axle cross section, making it as weak as the square taper axles again (With stress risers where the slot fo the bearing race is cut in the axle. If the bearing race is part of the axle and the red highlighting is just for display purposes then it's fine :).

The Chris King has two plates with radially toothed faces that push against each other with one turning with the hub and the other with the freehub. The helical gear bit you can see is the edge of the plate that turns with the freehub, so pedalling forces act to push the washers together more firmly. I haven't pulled one of these apart though, so can't say for certain. The picture is class for the expensive shinyness factor alone anyway.

Edited by psycholist
Link to comment
Share on other sites

The Chris King has two plates with radially toothed faces that push against each other with one turning with the hub and the other with the freehub. The helical gear bit you can see is the edge of the plate that turns with the freehub, so pedalling forces act to push the washers together more firmly. I haven't pulled one of these apart though, so can't say for certain. The picture is class for the expensive shinyness factor alone anyway.

Thats near enough right :)

I think.....

Red arrow is the ring drive teeth/rings.

Green arrow is the spring.

Blue arrow is where the helical bit is in the hub shell.

Chris_King_rear_hub_cutaway.jpg

edit: and a photo of a stripped king hub.

Hubdisas.jpg

Edited by forteh
Link to comment
Share on other sites

that hub uses the same internals as the superstar superleggra hub and the new halo star drive hub. it works how, dave said, the teeth are only there to initiate the engagement, once its started the harder you push on the pedals the more the pawl is forced up the ramp and into the drive ring. great in theory and according to the guys at superstar its been awesome on the DH and 4X bikes its been tested on; but completely unproven in trials.

Link to comment
Share on other sites

Thats near enough right :)

I think.....

Red arrow is the ring drive teeth/rings.

Green arrow is the spring.

Blue arrow is where the helical bit is in the hub shell.

The blue arrow is just the outside of the driven ring, that's just how it's pressed into the hub shell. You can't see the helical spined bit on that photo.

Link to comment
Share on other sites

The blue arrow is just the outside of the driven ring, that's just how it's pressed into the hub shell. You can't see the helical spined bit on that photo.

Yeah I meant to say that the helical spline is inside that bit :$

Those grooves, as you say, are only there to transmit the torque through to the hubshell, alot of intricate machining in a king hub :)

Link to comment
Share on other sites

I contacted Superstar about the rear hubs and got this reply:

Hello the hubs work like neither of the hubs you mention (King/I9 hubs). They use a sliding cam mechanism which is engaged by a fine toothed hardened steel ring. The power is transmitted by the cam mechanism not the teeth, the hubshell will fail much earlier than the cams breaking open the special hardened steel engagement ring.

The axle is oversized and aluminium and has withstood 8 months of 4x and jumping on my non XC bike.

1 year warranty, everything is replaceable. You must use a spidered cassette as the freehub is also T6 alloy.

No maintenance needed, but it is easy to pop off the freehub and clean any water or crap which has worked its way inside. Not a speck inside my 8 month old hubs so far.

Pictures:

Freehub.jpg

Engagement_ring.jpg

Still not too sure it would work for trials, but one may be appearing soon on my Giant Trance :)...

That they replied to me with pictures in less than a day is also way above and beyond what I've come to expect from any other online retailer :).

Edited by psycholist
Link to comment
Share on other sites

Im not doubting it lasts well under normal riding around, but trials will I imagine create some pretty large forces trying to burst the ratchet apart or squash the freehub. I'd be interested to try one though.

Link to comment
Share on other sites

I'd have my doubts about the trials durability, but I mostly posted because I was so impressed with the speed and the quality of the reply. Best reply I've got to a product question I've ever got from an online retailer. Most of them don't even want you to see inside the hub before you buy - shows a certain confidence I think...

Link to comment
Share on other sites

There are at least 4 brand name Hubs this year that are using 120clicks engagement system, and none of them are trials specific. Halo super DJ (dirt jump) hub is latest addition to join the 120click hub club. Chris King, Hope, and Middleburn, seemed to be either slow on the uptake, or not bothered of developing a super high engagement hub. maybe these companies are just waiting to see how these hubs perform long term.

Edited by Rusevelt
Link to comment
Share on other sites

There are at least 4 brand name Hubs this year that are using 120clicks engagement system, and none of them are trials specific. Halo super DJ (dirt jump) hub is latest addition to join the 120click hub club. Chris King, Hope, and Middleburn, seemed to be either slow on the uptake, or not bothered of developing a super high engagement hub. maybe these companies are just waiting to see how these hubs perform long term.

It's diminishing returns though isnt it? I noticed a nice difference between 16, 21 and 72 engagment points, I'm not sure I'd be so impressed going to 120 point.

All three firms you name, or the first two at least, have strong, reliable mechanisms. This one has a couple of fairly dubious points, and needs to be made with greater accuracy, so it's going to be expensive. Doesnt really strike me as worth changing to this mechanism for the small benefits.

Link to comment
Share on other sites

I contacted Superstar about the rear hubs and got this reply:

Pictures:

Freehub.jpg

Engagement_ring.jpg

Still not too sure it would work for trials, but one may be appearing soon on my Giant Trance :)...

That they replied to me with pictures in less than a day is also way above and beyond what I've come to expect from any other online retailer :).

That looks really good, quite a nice idea.

If a hope Xc can run for trials, im sure one of these could. I may try one, just to see...

Link to comment
Share on other sites

A friend of mine (Who's nothing like as hard as I am on hubs) has mashed the engagement system on his DT rear hub after under 2 years of XC only use. They're no longer on my list of good hubs. Theoretically they should be as strong if not stronger than Chris Kings thanks to the deeper ratchet teeth. In reality they're made from cheese, so they don't hold their shape. Chris Kings use the pedalling force to increase the force with which the ratchet washers are pressed against each other too, which helps with the freewheel hold.

Edited by psycholist
Link to comment
Share on other sites

A friend of mine (Who's nothing like as hard as I am on hubs) has mashed the engagement system on his DT rear hub after under 2 years of XC only use. They're no longer on my list of good hubs. Theoretically they should be as strong if not stronger than Chris Kings thanks to the deeper ratchet teeth. In reality they're made from cheese, so they don't hold their shape. Chris Kings use the pedalling force to increase the force with which the ratchet washers are pressed against each other too, which helps with the freewheel hold.

I find that interesting. I raced mine hard for a good 5 years including several 6hr 12hr and 24hr races and only replaced the odd bearing here and there. I used to ride everything in a 44T as well. I'm sure I could get another 5 years out of it.

Link to comment
Share on other sites

You may have a higher end hub though. Better materials and/or heat treatment possibly. The hub I saw fail came stock on a giant Trance 2...

It will no doubt be the cheaper ratchet and pawl style DT hub, not the Hugi 240/DT 240/340/440 with 'star ratchet' drive.

They are nice hubs, but are not designed for trials and still a long way off the performance of a Chris King. The system only has 18 engagements, and costs a fair bit more than the tried and tested Pro 2. The only person I know of that ran one for trials did get some good use out of it, but it did break.

Link to comment
Share on other sites

The way it actually engages is pretty similar to how a freecoaster's clutch presses against the hub shell. I use mine on my BMX to do brakeless fufanus on stuff, haul arse through traffic, and generally put a lot of pressure on it, and it's never slipped on me. This one seems like a pretty good idea, so it might not be as bad as everyone thinks. I doubt you'd be able to tear apart the hubshell purely from pedalling, just because that'd be the equivalent of ripping apart a regular hubshell from pedalling? The force is going around as well as outwards when it first engages, so it wouldn't all be just it expanding, so personally I doubt you'd be able to kill it. If the sprung parts are all made of good quality material too, it shouldn't have a problem. My freecoaster's splines haven't really worn out at all, they've just become incredibly sharp so it engages better.

Link to comment
Share on other sites

It's all down to material hardness. The issues with most hubs are not bad design, just bad implementation.

Here's another option: http://www.trueprecision.net/c_products_mountain.html - It uses a sprag clutch, which basically means instant engagement and silent freewheeling...

The sprag clutch is described here - once again if the sealing and materials are good it'll work perfectly: http://www.gmnbt.com/freewheel_technology.htm

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...