Full Sus.. 2:1 V X:X

The Northern Monkey
The Northern Monkey Posts: 19,174
edited January 2010 in MTB general
Howdy.

Forgive me if this sounds...... confusing?

Basically theres a few FS bikes out there that "brag" about having a 2:1 leverage ratio.. whats all that about?
Are there any benefits/disadvantages?
Whats a normal leverage ratio... 2:1 = every 2 inches of travel is damped by 1 inch of shock stroke.

Foes has a really good write up about it on their site but is it all just manufacturer spiel?

Comments

  • nicklouse
    nicklouse Posts: 50,675
    wheel travel to shock travel.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • jpstar
    jpstar Posts: 561
    so if the ratio was large enough, you could ride DH on a 4" shock? Does it effectively make a 5" worth 10" of wheel travel?
  • nicklouse
    nicklouse Posts: 50,675
    jpstar wrote:
    so if the ratio was large enough, you could ride DH on a 4" shock? Does it effectively make a 5" worth 10" of wheel travel?

    find me a 4"shock. there are none.



    aside that when the ratios get too big you are asking the shock to do alot more work which means heat which mean fade and more servicing.

    I wonder why Foes aim for a 2:1 ratio to reduce the work done and better control.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • Yup
    You could ride DH on a 0.1" shock with the right linkages! Probably wouldn't be very plush though....
    I think most FS are more like 3:1
  • nicklouse wrote:
    I wonder why Foes aim for a 2:1 ratio to reduce the work done and better control.

    you saying 2:1 does reduce work done + gives better control?

    whats that curnutt shock?not herd of that before!
    the other option is a fox DHX... i take it the 2:1 ratio will be kepth with the dhx?
  • BlackSpur
    BlackSpur Posts: 4,228
    Foes make their own custom long stroke shocks with Curnutt to get the leverage ratio they want.
    "Melancholy is incompatible with bicycling." ~James E. Starrs
  • supersonic
    supersonic Posts: 82,708
    As above, lower ratios allow a longer shock and lower pressures to be used, which increase sensitivity and help the damper perform.
  • ahh ok. So if you spec a dhxshock, it wont be a 2:1 ratio then?

    Wonder who imports them... Balfa are the Uk suppliers but it says you can only get them through bike shops.... anyone seen one around to have alook at?
  • supersonic
    supersonic Posts: 82,708
    Depensd on the mechanics of the sus design.
  • nicklouse
    nicklouse Posts: 50,675
    the shock has very little to do with it.

    the sus design does.


    the longest stroke on a DHX 3.5 so with a 2:1 ratio it would be a 7" travel design from a 10"i2i shock.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • ahhhh riight now we're getting somewhere lol!

    I think I know what you;re getting at now :)

    wish i'd done physics/mechanics lol!

    Itsthe DHX 5 air that comes as standard.
  • nicklouse
    nicklouse Posts: 50,675
    on what?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • nicklouse
    nicklouse Posts: 50,675
    it is an option. but not the recomended option.

    as it was designed to work with the foes shock.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • Fair enough :)

    nice frame though, bit different to other single crown FR/DH bikes!
  • The Foes RS7 can be run with a dual crown or single crown fork.

    On ALL Foes frames, the first thing to be designed is the shock itself. Brent getst them to work exactly how he wants & then builds a chassis around the shock.

    The Fox shocks are all very good today which is why more options are offerred than ever before on Foes. It also helps keep the price down.
    One if the disadvantages of running a Fox on a Foes is that you dont get the tru benefits of a 2:1 leverage ratio. 2:1 allows you to run far lower pressures to to the extra storke length & also the shock volumes - On a Fox i run approx 170PSI but on the same frame with a Curnutt Air i would run 70PSI!!

    This makes them much plusher an smoother on the trails.

    For those who havent heard of Curnutt, Charlie Curnutt Sr. came up with the Stable Platform damping design back in the 70's. Over the years, the patented technology has been licensed to other brands. Basically 5th Element & Manitou SPV shocks were all mass produced, smaller Curnutt shocks & for 2010, because Manitou are not using SPV, Fox have licensed the technology. Anything with an RC4 shock or FiT damping, has Curnutt damping inside.

    J
    Balfa, .243 racing, Avent and Bombshell importers,go on buy one!
    For Bargain Parts visit www.balfa.co.uk and go to the clearance pages
  • Jamie@Balfa
    Cheers for the write up!

    Balfa are the UK importers aren't they but you can't buy direct according to you're webby!
  • Check again - its been removed.

    You can now buy directly from us aswell as from your local Foes dealer. We have taken this step to avoid sny price rises in 2010, infact one or two models have come down in price.

    Best bet is to give us a call on 01442 826007 and we can talk you through any questions you have.

    Jamie
    Balfa, .243 racing, Avent and Bombshell importers,go on buy one!
    For Bargain Parts visit www.balfa.co.uk and go to the clearance pages