twin vs mono shocks

[Anonymous]

Assuming all shocks are high quality/performance shocks, does a monoshock give any better performance than twin shocks? Also assuming, that they are being used for racing or very spirited riding.

[Anonymous]

Nope.

The biggest advantage of a monoshock is price - there is only one to build, so it will cost half the price of the pair, assuming equivalent construction and quality. There may also be packaging benefits to a monoshock (easier to tuck in the exhaust can for instance), but with airboxes getting huge space is getting scarce for a shock in that central area, as well.

Both arrangements have advantages and disadvantages and which one is better would depend on the particular bike layout. There is so little space available on current sportbikes that packaging considerations are almost the paramount priority, with everything else coming in second to that.

There, if that doesn't stir things up a bit nothing will...


Mark

[saaz]

The only technical advantage I can really see for mono shocks is that a rising rate can be built into the linkages. The Japanese CB1300 (last model) had some sort of rising linkage for its twin shock system, so this may not necessarily be an inherent advantage for mono shocks. Also twin shocks can have multi rate springs and multi stage damping. I run the Fournales air shocks that have an infinite rising rate. I think Yamaha was also playing around with twin shocks as part of a fundamental frame redesign.

I think the short answer is that it depends on the overal bike design! A mono shock might leave room for panniers etc, but gets in the way of under seat exhausts. More questions than answers really.

[Anonymous]

Judging from the shocks I've replaced, the monoshock is much more expensive, much harder to adjust, and lasts apprx. half as long, cause the 1 shock is doing the work of the 2 that that the other system does. It takes 20 min. to change 2 shocks, and a half of day to change the monoshock. I haven't seen any advantage yet, but I'm still looking for one.

[Hoomgar]

Judging from the shocks I've replaced, the monoshock is much more expensive, much harder to adjust, and lasts apprx. half as long, cause the 1 shock is doing the work of the 2 that that the other system does. It takes 20 min. to change 2 shocks, and a half of day to change the monoshock. I haven't seen any advantage yet, but I'm still looking for one.

If you shop around I think you will find that what rphillips just said is very true. The high quality mono's can really set you back. Even more than a pair of high quality twin shocks in a lot of cases. And they do wear out faster. But on the flip side it is what you see on most of the newer sport bikes. The main reason for a mono is a smoother ride from what I am told. I think it is something you just have to decide on based more on what your bike will take.

[Anonymous]

The high quality mono's can really set you back. Even more than a pair of high quality twin shocks in a lot of cases. And they do wear out faster. But on the flip side it is what you see on most of the newer sport bikes.

The extra cost of a single shock would be related to the fact that only Ohlins and Penske make really high quality dual shocks setups and nobody is considering them it seems. You can buy a Penske twin clicker for about $750-800USD and I am sure their dual shock setups will be much more than that. The Ohlins are also more than a bit pricey, too. Any other twin shocks I have seen are simply old technology that does not compare to current aftermarket monoshocks.

Partly the monoshocks do cost more because they are heavily leveraged and run stiff springs and deal with higher forces than twin shocks do, so they have to be made heavier than one of the pair of shocks.

I have never noticed that a monoshock wears out faster, but I also don't have enough miles on a twin shock bike to have a really good basis for comparison for that.

[Anonymous]

Sorry, I don't know about the high quality shocks, but there are new, dual shocks, advertised all the time on e-bay for $100. The cheepest monoshock I could find to replace my warn out at 10,000 mi. GS 1150 shock was from "WORKS", right at $500. They have three more, more expensive models. I haven't given up, I'm still looking for an advantage.

[Anonymous]

Sorry, I don't know about the high quality shocks, but there are new, dual shocks, advertised all the time on e-bay for $100. The cheepest monoshock I could find to replace my warn out at 10,000 mi. GS 1150 shock was from "WORKS", right at $500.

The dual shocks you mention are no more sophisticated than the stock dampers were in 1983 (and will perform as such), while even the Works Performance mono is a step up in terms of its damping systems. As I said, the mono's do cost more than half of a pair because they are bigger and heavier (more material costs), but there is no excuse for being 5x the price. I bet the market is just brainwashed into thinking that mono's are superior and should cost more...For that $500 you can almost get a Penske Sport Shock from Traxxion Dynamics, they are $595 I think. And the Penkse will blow away the Works shock in every way possible. Check out www.traxxion.com if you are interested in a look at them. BTW, I have no affiliation with Penske or TD, but the products are top notch, if expensive.

There are no real advantages to a mono and a big cost disadvantage if you are not looking for top performance, as you note. Even a set of Works or Progressive Suspension shocks is a big improvement over the stock units and are more than adequate for a GS on the street. There are a lot of other things to sort that have a bigger effect on handling than the difference in performance between the Progressive shocks and a set of Ohlins or Penske shocks.

Mark

[Anonymous]

Other advantages of monoshocks are consistent control. While it may not be that noticeable, twin shocks have to be set up the exact same as each other for maximum performance. For this reason, one is always better than two, but the average rider won't care. It matters more for all-out sportbike performance.
Also, if you don't do your own work, service rates are WAY higher for a monoshock as it takes ages to get one off the bike. We all know that removing twin shocks takes all of 5 minutes.
Finally, OEM monoshocks usually have much more adjustability than twin shock setups.

[Clone]

I remember seeing a post in one of the shock discussions saying that a suspension tuner should be able to rebuild your stock monoshock. I also queried a hydraulic shop which rebuilds cylinders if rebuilding a shock is possible. They said they would give it a shot if I wanted, all the parts inside are fairly common, but would not offer any gurantees( I spelled that wrong, but can't to save my life think of the correct spelling). The cost of rebuilding would range from $45 to $100 give or take a little, depending on the trouble of opening and sealing the cap.

[Anonymous]

I remember seeing a post in one of the shock discussions saying that a suspension tuner should be able to rebuild your stock monoshock.

Depends on the shock and the tuner. Some OEM shocks are reasonable to rebuild, others not. Some tuners will do it, some not. Race Tech (http://www.racetech.com) will do a lot of stock ones, but I am not sure if they go as far back as the GS's. Lindemann Engineering will also do most shocks as well. LE were willing to try on just about any shock I could name when I contacted them a few years ago. Price at the time was about $75US plus parts for a simple oil change and new seals. There is a local tuner here (Calgary, Alberta, Canada) who is willing to do most OEM shocks if it is possible. Price is $40CDN plus parts for an oil change, $200CDN plus parts for a complete revalve.

I would be skeptical of having a cylinder shop rebuild a shock. Most OEM shocks require grinding the end of the piston rod off to remove the nut holding the piston on and if done incorrectly it can ruin the shock. Shocks are much more complicated internally than damping rod forks and require a bit of care to do properly. This is relating to newer shocks, though. Perhaps the OEM GS shock in question is simple enough to not be an issue.


Mark

[Anonymous]

The advantages of a monoshock lie in the linkages. They can be designed with compression rates that are dependant on position, rather than the linear relationship associated with twin shocks.

One side advantage of a mono is that with twin shocks there is always a difference in characteristics from one side to the other. This can produce a flex in the swingarm. The monoshock design eliminates this.