I posted the reply below in another thread. After re-reading it a question came to mind. When someone asks a question what are they looking for? An answer based on opinion, on a consensus of opinions, an answer based on technical training and if so what is the background? Someone once said you are entitled to your opinion but not your own facts. Is this the wrong list for this type of debate?
Equal travel up and down is wrong. That is not the aim of setting the proper sag.
Like Greywolf stated the proper sag should account for only 25%-33% of the usable travel of the suspension. I would advise closer to 33% if you venture off the pavement or closer to 25% for track days.
What I find really discouraging is how much emphasis is put on the sag measurement and how little most put on suspension. Most here understand correctly that sag should be 25-33% of the total travel. Sag is just a "static" measurement to determine how much of your total travel of suspension is being used to hold up the bike. Nothing more. What is left over is what you have left of travel. Ideally you should have as much travel in either direction. If we road on a perfectly flat surface where the only bit of suspension travel would be compression due to an obstacle like a board or such then we wouldn't need to be as concerned about whether we had equal travel to absorb as to let the wheel drop into a hole. Even a racetrack doesn't have a surface like that. I'm not trying to be difficult but is there anybody out there that would be satisfied if their suspension only worked well for half the surfaces they would be riding on?
I have read things here like crank the preload all the way. Things like you don't need your suspension to ride in the middle if it's suspension. If any professional racer heard someone say that they would never let whoever said it near their bike. Even on a track where they don't need as much travel they will shorten the travel but still have the same travel in both directions. Otherwise if a wheel comes off the road they don't have enough travel to absorb the pounding when that wheel comes back down.
Any manufacturer of suspension equipment like RaceTech, Traxxion, Penske and so on have built their business with the same goal in mind: Keep the wheels on the road and keep the bike as level as possible while doing so. If Valintino Rossi rode Nicki Hayden's bike and vise versa they probably would finish third and forth. The 5 pounds different between them would make a world of difference on their bikes. I'm not trying to say we should be either of them on the road but the aspect of tuning our suspension for ourselves is the same. The principles of how our suspensions work doesn't change. Maybe I'm a cockeyed optimist but I would assume everyone here would like their bikes to perform at its optimum ability. Of course the amount of money you want to spend is a factor. But, whether you spend $100 or $3000 to upgrade your suspension it will still "work" the same way, only better. Whether you ride a Strom, a Harley, a Wing, a Duck or any bike with a suspension it is "not" designed for the travel to be more in one direction than the other. It is because a bike "designed" for a 155lb rider has a 200lb rider in the saddle that the geometry changes. The physics don't change, just the parts to compensate for the added weight. Would anyone here spend $1200 for a rear shock? If you had it and you felt what it could do to improve your bikes performance you probably would. On the other hand for some it would be a waste of money.
Just like what I have written here. Some will read it and do their own research. Some will say that makes sense. Some will read it and say it is Bunk. Some won't even read it. My tag line usually is "A man convinced against his will is of the same opinion still." I guess the world I live in, the level of professionals from whom I have gotten the information I share, is not reliable to some here. That is fine with me. It's like the Darksiders. What they do on their bikes is fine with me and I won't debate the pros and cons. Would I do it to my bike? No. I don't know any professional at the top of the industry that would even consider it. It's like the people that refuse to wear a helmet. I won't debate that issue. What someone else does is fine with me. Again, I don't know a single professional at the top of the riding industry that would think of not wearing a helmet. I'm not saying I am in their league at the top of the industry but I will say they are the people that I associate with. Will I comment on every thread? No. Most of the time I won't or wouldn't be the first person to answer a question even if I knew the answer. But when I read a reply that is off base and contrary to the standards excepted by the top professionals in the industry I will challenge. I would expect no less from anybody with more training. Me, I am "E" challenged. If it has a wire I am sol. A good friend, Tracey Martin, wrote the book on Motorcycle Electrical Systems. Read it, watched him do marvels but no matter how much I try I can't wrap my head around it. I can guarantee I won't be responding to much about wiring. But, when it comes to safety, riding techniques, long distance riding and suspensions, these are in my wheelhouse.