Twin shocks vs. monoshocks?

Discussion in 'The Perfect Line and Other Riding Myths' started by SloMo228, Apr 30, 2014.

  1. scootrboi

    scootrboi Long timer

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    The single shock designs are heavier.
    #21
  2. slartidbartfast

    slartidbartfast Love those blue pipes

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    The BMW monolever swingarm was both lighter and stiffer than the twin shock design it replaced
    #22
  3. scootrboi

    scootrboi Long timer

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    I am enjoying my wrongness because I prefer one sided designs. I suppose it might have to do with the light alloy castings used.
    #23
  4. eric2

    eric2 ®egister this:

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    Bikes were all twin shocks until the '70s. Maico started the long travel trend by moving the twin shocks forward.

    I can't believe this hasn't been mentioned, but the monoshock design was done by an elementary aged kid. An engineer from yamaha saw the design on the playground and the next year yamaha made the first monoshock based dirt bike from the stolen plans.

    The kid ended winning millions of dollars later on in court.
    #24
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  5. scootrboi

    scootrboi Long timer

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    My 1960 scooter has a monoshock swingarm suspension patented around 1951 by Heinkel.
    #25
  6. slartidbartfast

    slartidbartfast Love those blue pipes

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    Where did you hear that one? :lol3

    Vincent beat Yamaha to the underseat monoshock by 30+ years and Flying Merkel, amongst others, had similar systems 30+ years before that.
    #26
  7. markk53

    markk53 jack of all trades...

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    The forward mount twin shock was a home brewed modification. Maico just took to it sooner. Roger DeCoster had to cut up his own frame and do it himself, Suzuki engineers wouldn't do it. He had to do it to keep up with the rest.

    Tilkiens was the originator of the monoshock set up bought by Yamaha. Not sure where the elementary school kid story came from. Tilkiens son raced CZ and a crash caused by hard bottoming in the rear brought about the change.

    By the way, Vincent actually uses TWO shocks under the seat, oddly enough:

    [​IMG]
    #27
  8. markk53

    markk53 jack of all trades...

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    Doesn't mean I was wrong. It is still a serious strong swingarm.

    Oddly enough, Ducati used twin arm swingarms on its factory superbikes for a while at least. Lighter and less flex in their case.
    #28
  9. portalespeanut

    portalespeanut nEARLY nORMAL

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    Interesting question...there's a world of difference between the either system depending if you're considering 'highway' or 'offroad'. I would like to speak to the offroad side of this discussion - First, many of the developments in suspension have been born out of the dirtbike world with single shock rising rate suspensions finally taking over from the twin shock world...for many reasons. While rising rate single shock suspensions are the norm for offroad, I will say that some of the last long travel twin shock setups on some dirtbikes of the '80's (yes, I'm old), were incredible.

    Case in point, I have a '80's model Husky with the twin shock configuration...it has the Olins remote res. style shocks with about 13 inches of travel that have been tuned by Scotts Suspensions. The quality and quantity of the suspension travel is incredible...and surprisingly good, even today. It was superior to the single shock rising rate CR500 which replaced it in my barn at that time. Recently, I took the old Husky off-roading with some friends, and one of my buddies wanted to swap bikes for a bit so he could sample a 'vintage bike'. He was shocked (no pun intended) at the suspension, remarking, "This thing is awesome across the desert...it eats everything in sight!...but where's the brakes!!!" The old Husky has a surprisingly competent suspension, even by today's standards...as long as one's not comparing it to the latest in pro level competition machinery.

    A good, well tuned twin shock setup is an excellent suspension...my Husky can still cross brutally rough terrain at speed with great control...it's only shortcoming is that it's slightly more 'harsh' due to the fact that it's not a rising rate suspension. While not super plush, it is competent and confidence inspiring, always working with you, and never surprising you. Single shock suspensions rule now, and are tuneable, versatile, and reliable...they rule for good reason, but they are NOT the only way to suspend a rear end of a bike...just my .02 cents...
    #29
  10. joexr

    joexr Banned

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    I believe the KaTooMs STILL use linkless rear shocks.
    #30
  11. ttpete

    ttpete Rectum Non Bustibus

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    Lots of today's bikes do. Not uncommon at all. Kawasaki Versys, ER-6, and Ninja 650R have them.

    Vincent motorcycles patented and used the single shock design beginning in 1928.
    #31
  12. erkmania

    erkmania Last of the red hot left pipers

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    While still true, not all KTM's are linkless anymore. Their 350's and 450's are sporting linked rear suspension these days. I think they must have detected a need for change since most everyone else in MX land is using linked rising rate rear suspensions. It makes sense since a fork is usually a progressive suspension because of the trapped air volume.

    Apparently, there are pros and cons to each setup from what I have read.

    No one has mentioned Ducati here to my knowledge, so I will. They have gone to linkless (cantilever) shocks in their Monster series. They do use progressive springs, though. I think they did that to save money and weight while mimicking linked suspension the best way they can . What do you all think?

    BTW, welcome back from Banned Camp, Joe. :deal
    #32
  13. ttpete

    ttpete Rectum Non Bustibus

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    I also think that it's done for cost reasons. There are variations in the linked suspension, mostly done on the racebikes, that make them non-rising rate.

    If you get a chance, have a look at the setup on the 1199 Panigale. It's unique due to the fact there's no actual frame.
    #33
  14. joexr

    joexr Banned

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    Depending on the cantilever geometry , it could be rising or falling rate and not necessarily from the factory , but easily varied.
    #34
  15. erkmania

    erkmania Last of the red hot left pipers

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    I looked at the Panigale. It appears to have a link despite it's...um... 'frameless-ness'. :1drink Do you see it?

    OK, now how do I shrink the image I linked? Sorry for it being over-sized.

    [​IMG]

    [​IMG]
    #35
  16. erkmania

    erkmania Last of the red hot left pipers

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    Too true. I don't really remember a digressive cantilever being used, though. Most are progressive. My ATK is a good example. I think both you and I know that progressive linkages are nothing more than stacked cantilever designs.
    #36
  17. joexr

    joexr Banned

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    It's kind of hard to see with the downward angle of the pic what the change in geometry does by relocating that center pivot point on the cantilever.
    #37
  18. daviethebiker

    daviethebiker Adventurer

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    I have a 1984 Husqvarna 500xc that uses two shocks in the rear. The bike is stock and has 13.8 inches of rear wheel travel.
    #38
  19. markk53

    markk53 jack of all trades...

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    Like I said, the main con is the shock is exposed to be bent, that's about it. They can work incredibly well.
    #39
  20. markk53

    markk53 jack of all trades...

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    I don't know about the single shock, all the big twins from the forties and fifties had TWO shocks in there. Fact is every one I've seen with original frames had the triangular swingarm with twin shocks.
    #40