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Discussion Starter · #1 ·
Hi, if anyone can help clear this up it would be greatly appreciated. I weigh 170 pounds. What should my sag rate be set to. If this is a stupid question please excuse me because I really don't understand much of this stuff. I have a PP with about 2,000 miles on it. I leave it in sport mode all the time because the ride feels very comfortable and compliant. But I noticed when I'm aggressively riding through the mountain twisties the bike does not feel planted or confidence inspiring. I tried setting this with one rider up with luggage and it didn't seem to make things feel any different or any better. Any suggestions or feedback would greatly help. I was told by Boulder Motor Sports I should put on the heavier springs front and rear and that would make my bike handle a lot better. I'm not so sure I would need to do that since I'm only 170 and most guys seem to be a lot heavier and so need to do that spring change. I could really use some help here please. Thanks for anything you guys can offer.
 

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Hi, if anyone can help clear this up it would be greatly appreciated. I weigh 170 pounds. What should my sag rate be set to. If this is a stupid question please excuse me because I really don't understand much of this stuff. I have a PP with about 2,000 miles on it. I leave it in sport mode all the time because the ride feels very comfortable and compliant. But I noticed when I'm aggressively riding through the mountain twisties the bike does not feel planted or confidence inspiring. I tried setting this with one rider up with luggage and it didn't seem to make things feel any different or any better. Any suggestions or feedback would greatly help. I was told by Boulder Motor Sports I should put on the heavier springs front and rear and that would make my bike handle a lot better. I'm not so sure I would need to do that since I'm only 170 and most guys seem to be a lot heavier and so need to do that spring change. I could really use some help here please. Thanks for anything you guys can offer.
Well now, that depends.... I weigh 178.5 lbs without gear, and I went to the heavier springs, mainly for two up riding with luggage...however, it does transform the bike....as does dropping the yoke through the forks by 8mm.

Sag? Now that depends on you and the bike....you really need to measure it.
 

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Cant remember what the

Number is ( mm sag I think between 35-40mm ) Im the same weight as you and my sag fell perfectly with the stock lighter spring. BMS set my sag. Get it set by doing the measurement then if you don't like it ( also play with your rebound and comp) then change the spring..
 

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Lionsgate, the stock springs should accommodate you and luggage for certain. I would think that a sag measurement between 35mm and 50mm would suffice. I'm the same weight as you and my bike sits in the 40s. Damping is all up to you, I like less compression and slower rebound. Remember that the numerical range of the damping settings is in inverse order (lowest number = highest setting).

Edit: free sag should be considered in the measurement/determination as well
 

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Always set the sag first on any bike! Setting the sag puts the suspension in the proper position for your weight and allows the Comp and Rebound to work effectively.

Numbers on the Multi are a bit higher due to the increased travel this bike has. 56MM is the recommended front and rear sag. Sag should be 30% to 35% or 1/3 of the total travel.
 

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Always set the sag first on any bike! Setting the sag puts the suspension in the proper position for your weight and allows the Comp and Rebound to work effectively.

Numbers on the Multi are a bit higher due to the increased travel this bike has. 56MM is the recommended front and rear sag. Sag should be 30% to 35% or 1/3 of the total travel.


And there you go!:)
 

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Always set the sag first on any bike! Setting the sag puts the suspension in the proper position for your weight and allows the Comp and Rebound to work effectively.

Numbers on the Multi are a bit higher due to the increased travel this bike has. 56MM is the recommended front and rear sag. Sag should be 30% to 35% or 1/3 of the total travel.
Bingo. Sag should be thought of as a percentage of total suspension travel.

At 170lbs I would think the stock springs should be just fine for you. Remember, changing the sag will not make you bike suspension stiffer (or less stiff), it is only changing the equilibrium position.
 

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Discussion Starter · #8 ·
Setting the Sag

Thanks guys for your help and info. I will certainly have Boulder Motor Sports set up my Sag over the next week or two. As soon as they get my MIVV decat pipe in and re-flash my ECU. It certainly makes much more sense to have the suspension all set optimally and play with the settings more then changing springs, which really never made much sense to me in the first place. It would be like putting the cart before the horse in a way. Hope I'm making the right choice with the MIVV decat and re-flash and its not too loud. I've read all the post and then decided to go in that direction. Also will probably put the 14t front sprocket on as well. I'll post after its all done and let everyone know how it all went and what the changes did for me. Regards to all and thanks again.
 

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comp/rebound settings

Curious. Those that have changed the comp/rebound damping, what have you changed it to? I'm still at factory default on all but sport but have been experimenting "solo" setting in sport.

I'm stock springs front with 6/9 and 100Nm spring in rear with stock setting. 210# w/gear. Sporting riding style.
 

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i spoke to Dan Kyle today of Dan Kyle Racing (one of the true Ohlins authorities out there)......asked him the question as to what the proper sag should be for the MTS12.....answer: 30% of the available suspension travel in the front, and 40% of the available suspension travel in the rear. if the MTS12S' suspension travel is 170mm both front and rear, then the front should sag 51mm and the rear 68mm. that seems odd to me, and unless i misheard him (could it have been front 40% and rear 30%??), those would be the corresponding stats. while he did not have the rear suspension travel data in front of him, he did not think the front and rear travel would be the same (170mm/6.7in is well documented me thinks).

that's what i know.
 

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i spoke to Dan Kyle today of Dan Kyle Racing (one of the true Ohlins authorities out there)......asked him the question as to what the proper sag should be for the MTS12.....answer: 30% of the available suspension travel in the front, and 40% of the available suspension travel in the rear. if the MTS12S' suspension travel is 170mm both front and rear, then the front should sag 51mm and the rear 68mm. that seems odd to me, and unless i misheard him (could it have been front 40% and rear 30%??), those would be the corresponding stats. while he did not have the rear suspension travel data in front of him, he did not think the front and rear travel would be the same (170mm/6.7in is well documented me thinks).

that's what i know.
I would say it should be MORE in the FRONT than rear, but Dan knows suspension
 

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Discussion Starter · #12 ·
sag

Originally Posted by oalvarez
i spoke to Dan Kyle today of Dan Kyle Racing (one of the true Ohlins authorities out there)......asked him the question as to what the proper sag should be for the MTS12.....answer: 30% of the available suspension travel in the front, and 40% of the available suspension travel in the rear. if the MTS12S' suspension travel is 170mm both front and rear, then the front should sag 51mm and the rear 68mm. that seems odd to me, and unless i misheard him (could it have been front 40% and rear 30%??), those would be the corresponding stats. while he did not have the rear suspension travel data in front of him, he did not think the front and rear travel would be the same (170mm/6.7in is well documented me thinks).

I thought the sag had to be set for the individual rider while he sat on the bike. So is it that once the rider is sitting on the bike the front and rear sag are set to the specs above? Also is the available suspension travel measured while the bike is on the center stand or as the bike is sitting on its wheels no rider on? Sorry if these are stupid questions but I'm just trying to understand this all.:confused:
 

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There are countless threads on what sag is and how sag is measured (completely unloaded tires in air minus the average of two different loaded measures), give them a read. The preload is adjustable on most springs allowing the rider to dial it in for his weight. Knowing the recommended percentage of suspension travel in relation to sag or the actual sag for the bike in question is what you will need to know. Have a friend help you with the measurements and go from there. :)

Take care and have fun,
 

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Good basic primer for setting sag.Suspension and Springs - Sag
What's all this ruckus about suspension these days? It seems everyone is clued in that suspension setup can be a key to riding fast and safely, but how do you do it? No matter what shock or fork you have, they all require proper adjustment to work to their maximum potential. Suspension tuning isn't rocket science, and if you follow step-by-step procedures you can make remarkable improvements in your bike's handling characteristics.*
The first step to setting up any bike is to set the spring sag and determine if you have the correct-rate springs. Spring sag is the amount the springs compress between fully topped out and fully loaded with the rider on board in riding position. It is also referred to as static ride height or static sag. My company, Race Tech, 951.279.6655 has an advanced method of checking spring sag that I'll describe.
If you've ever measured sag before, you may have noticed that if you check it three or four times, you can get three or four times, you can get three or four different numbers without changed anything. We'll tell you why this occurs and how to handle it.
REAR END 
Step 1: Extend the suspension completely by getting the wheel off the ground. It helps to have a few friends around. On bikes with sidestands the bike can usually be carefully rocked up on the stand to unload the suspension. Most race stands will not work because the suspension will still be loaded by resting on the swingarm rather than the wheel. Measure the distance from the axle vertically to some point on the chassis (metric figures are easiest and more precise; Figure 1). Mark this reference point because you'll need to refer to it again. This measurement is L1. If the measurement is not exactly vertical the sag numbers will be inaccurate (too low).*
Step 2: Take the bike off the stand and put the rider on board in riding position. Have a third person balance the bike from the front. If accuracy is important to you, you must take friction of the linkage into account. This is where our procedure is different: We take two additional measurements. First, push down on the rear end about 25mm (1") and let it extend very slowly.*
Where it stops, measure the distance between the axle and the mark on chassis again. If there were no drag in the linkage the bike would come up a little further. It's important that you do not bounce! This measurement is L2.
Step 3: Have your assistant lift up on the rear of the bike about 25mm and let it down very slowly. Where it stops, measure it. If there were no drag it would drop a little further. Remember, don't bounce! This measurement it L3.*
Step 4: The spring sag is in the middle of these two measurements. In fact, if there were no drag in the linkage, L2 and L3 would be the same. To get the actual sag figure you find the midpoint by averaging the two numbers and subtracting them from the fully extended measurement L1: static spring sag = L1 -[(L2 + L3) / 2].*
Step 5: Adjust the preload with whatever method applies to your bike. Spring collars are common, and some benefit from the use of special tools. In a pinch you can use a blunt chisel to unlock the collars and turn the main adjusting collar. If you have too much sag you need more preload; if you have too little sag you need less preload. For road race bikes, rear sag is typically 25 to 30mm. Street riders usually use 30 to 35mm. Bikes set up for the track are compromise when ridden on the street. The firmer settings commonly used on the tract are generally not recommended (or desirable) for road work.
You might notice the Sag Master measuring tool (available from Race Tech) in the pictures. It's a special tool made to assist you in measuring sag by allowing you to read sag directly without subtracting. It can also be used as a standard tape measure.*
Measuring front-end sag is very similar to the rear. However, it' much more critical to take seal drag into account on the front end because it is more pronounced.
FRONT END 
Step 1: Extend the fork completely and measure from the wiper (the dust seal atop the slider) to the bottom of the triple clamp (or lower fork casting on inverted forks; Figure 2). This measurement is L1.*
Step 2: Take the bike off the sidestand, and put the rider on board in riding position. Get and assistant to balance the bike from the rear, then push down on the front end and let it extend very slowly.

Where it stops, measure the distance between the wiper and the bottom of the triple clamp again. Do not bounce. This measurement is L2.*
Step 3: Lift up on the front end and let it drop very slowly. Where it stops, measure again. Don't bounce. This measurement is L3. Once again, L2 and L3 are different due to stiction or drag in the seals and bushings, which is particularly high for telescopic front ends.*
Step 4: Just as with the front, halfway between L2 and L3 is where the sag would be with no drag or stiction. Therefore L2 and L3 must be averaged and subtracted from L1 to calculate true spring sag: static spring sag = L1 - [l2 + l3) / 2].*
Step 5: To adjust sag use the preload adjusters, if available, or vary the length of the preload spaces inside the fork.*
Street bikes run between 25 and 33 percent of their total travel, which equates to 30 to 35mm. Roadrace bikes usually run between 25 and 30mm.*
This method of checking sag and taking stiction into account also allows you to check the drag of the linkage and seals. It follows that the greater the difference between the measurements (pushing down and pulling up), the worse the stiction. A good linkage (rear sag) has less than 3mm (0.12") difference, and a bad one has more than 10mm (0.39"). Good forks have less than 15mm difference, and we've seen forks with more than 50mm. (Gee, I wonder why they're harsh?)*
It's important to stress that there is no magic number. If you like the feel of the bike with less or more sag than these guidelines, great. Your personal sag and front-to-rear sag bias will depend on chassis geometry, track or road conditions, tire selection and rider weight and riding preference.*
Using different sag front and rear will have huge effect on steering characteristics. More sag on the front or less sag on the rear will make the bike turn more slowly. Increasing sag will also decrease bottoming resistance, though spring rate has a bigger effect than sag. Racers often use less sag to keep the bike clearance, and since roadraces work greater than we see on the street, they require a stiffer setup. Of course, setting spring sag is only first step of dialing in your suspension, so stay tuned for future articles on spring rates and damping.*
-Paul Thede

Magazine: Sport Rider 
Issue : August 1995
 

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Discussion Starter · #15 ·
Sag

Wow Wheels thanks that's the most extensive explanation I've read thus far. Appreciate it.
 
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