[taxonomy]

Anyone have suggestions for front and rear starting points for setting sag? It's a gen 1 with the ride height out back kicked up about 1.5 in I would guess.

Right how it's 30 front and rear. Some have suggest going 35 front and 30 rear. Is this conventional wisdom? Typical sporty spice rider. Not an animal, think Aerostich guy fast.

Sorry for what is almost surely a repost but I was wading through so much junk trying to find the answer.

 

[RichDesmond]

Anyone have suggestions for front and rear starting points for setting sag? It's a gen 1 with the ride height out back kicked up about 1.5 in I would guess.

Right how it's 30 front and rear. Some have suggest going 35 front and 30 rear. Is this conventional wisdom? Typical sporty spice rider. Not an animal, think Aerostich guy fast.

Sorry for what is almost surely a repost but I was wading through so much junk trying to find the answer.

30mm in the the rear is fine. Up front I usually shoot for 32-33 on street bikes. A couple of mm either way is going to be hard for the average guy to feel, so don't get too anal about it.
BTW, once you have a good sag measurement you don't need to keep redoing it. As long as you're making small changes there's a 1:1 correspondence between preload and sag. To get 3mm more sag just take out 3mm of preload.

 

[eddiemon]

I was just at s suspension clinic at Ducati / Triumph in Brea CA, some head guy will find his name later but he said 40mm for front and 30mm for rear.

 

[andyauger]

Rule of thumb is 10% of travel static sag, 30% of travel total sag. For bumpy streets it doesn't hurt to have a bit more static sag (prevents top out when running over dips and holes).

Front travel is 130mm, rear is 125mm. From the factory SVs come in around 25mm static sag. That says that with the correct springs for your weight total sag would be around 50mm.

If you don't have the right springs you cannot achieve a good sag setup. All you can do is set the ride height with preload adjustments.

 

[taxonomy]

I have good springs, .85s up front and I weigh around 180, a 600# in the back. I am very happy with those springs. I seem to be hitting pretty close to the race/static sag ratios that are desired.

I've got 30/35 r/f now. So, now I guess I go ride it some. It's finally, finally going to be warm enough this weekend in New England.

Thanks all

 

[andyauger]

That's plenty close enough. If you find you are bottoming out on rough roads you can just add some preload. If you are topping out then take some preload out.

 

[eddiemon]

Here is the info from an ocmoto thread:

http://www.ocmoto.com/index.php?topic=12960.0

 

[30x26]

according to ohlins:
38-40mm front
30-32 rear

 

[eddiemon]

I was just at s suspension clinic at Ducati / Triumph in Brea CA, some head guy will find his name later but he said 40mm for front and 30mm for rear.

Here's some pics I took at the suspension clinic:

 

[andyauger]

30X26, yep, those numbers are right there in the 30% total sag range.

The importance of knowing both the static and total sag is to see what the spread is. How much compression does the rider add to the preloaded suspension? The spread between static and total indicates how close the spring rates are to "ideal" for the rider's weight.

There is a fair amount of latitude, none of this is set in stone, and different people do have different preferences. 10% / 30% is a good starting point.

 

[jdewkilla]

numbers

 

[30x26]

30X26, yep, those numbers are right there in the 30% total sag range.
10% / 30% is a good starting point.

imho stock numbers are the first rule.
if a stock bike has about xx mm of difference between front and rear , a balanced upgraded bike should have about xx mm of difference. otherwise handling will be different (better or worst depends on the rider).

probably we already talked about the rule you suggest
imho this rule doesn't work on sv650: rear suspension has more travel but i've never seen a "properly" handling bike running more sag in the rear (i'm talking about stock bikes, without dogbones or lowered clamps).
imho that rule doesn't work in the front too. assuming 130 of travel (unreal, because my k3 has 120mm and 130mm of travel would cause the seals to touch the lower clamp) it will be 13mm static and 39 rider. that means a huge preload over a spring softer than stock one. a similar setup bottoms out under heavy braking (even with high oil level).
as i know common front numbers are:
25-28mm static
35-40mm rider

 

[andyauger]

That's what I said as part of my reply somewhere. I said that the stock SV has about 25mm static sag up front, and that's fine. You still want another (roughly) 25mm of sag when the rider is on the bike. So 25mm static and 50mm total would be a good setting.

If the spring is too soft you could have numbers like 25 static and 75 total. If the spring is too stiff then you could have numbers like 25 static and 35 total (both examples are exaggerated a bit). Numbers like that say you have the wrong springs.

Once you make a setting you watch for either bottoming out or topping out in your normal riding, adjust as needed. The smoother the roads you ride the less any of this matters. The rougher the roads the more it matters.

 

[Veee]

That's what I said as part of my reply somewhere. I said that the stock SV has about 25mm static sag up front, and that's fine. You still want another (roughly) 25mm of sag when the rider is on the bike. So 25mm static and 50mm total would be a good setting.

if you don't go over 30 mph that would be just fine ;D
10%/30% is not 25/50, not even remotely close.that is more like 20%/40%

 

[andyauger]

Let me try again. Preload sets the ride height of the bike. It also sets the "starting point" for the suspension.

Let's look at the 10% / 30% numbers. This is a recommendation found in many preload setting procedures. The difference between 10% and 30% is 20%. Wherever you start, if your springs are right you will get a change between static and total sag of around 20% of total travel. With the SV that's around 25mm. Remember, the DIFFERENCE between static and total sag should be around 20% of total suspension travel if the spring rate is right.

So suppose you want to start at 25mm (about 20% of total travel) static sag. If your springs are about right for your weight then your total sag should be about 25mm additional, or 50mm total sag. Suppose you measure the difference between static and total sag on your bike and it comes out anywhere from 20% to 30%. Would you change springs? I wouldn't. That's close enough.

Let's suppose your bike shows 25mm static and 50mm total sag. Streets you ride are pretty bad and you're topping out frequently. You take some preload out so you now have 35mm static sag. What's your total sag? Answer: 60mm.

Suppose you are racing and you find under heavy braking you are bottoming out. You crank in more preload so your static sag is 10mm. What's your total sag? Answer: 35mm.

The 25mm sag due to rider weight will stay the same with those springs. Changing preload does not change the spring rate.

Also, some people prefer softer springs, some prefer stiffer springs, no matter what the numbers say. There's a good bit of personal preference involved. Starting guides are just that, starting guides. With experience riders zero in on what fits them best.

 

[Veee]

I would not ride bike with 25/50. I know it will bottom.

 

[eamonnconnor]

Quick Noob question threadjack here -

I just installed .80 sonicsprings fork springs with 20 wt....about to install an 03 636 rear shock...what if any settings adjustments do I have to make once I install both parts?

 

[andyauger]

So, Veee, 10%/30% is wrong, 25mm/50mm is wrong. What are your sag numbers, static and total?

 

[taxonomy]

Pretty much every guide I have seen says somewhere between 30-40, with 40 being the road end. I've never seen 50.

10/30 is pretty much standard as far as I know.

 

[andyauger]

Taxonomy, all this is guidelines, not hard and fast rules. Go back and read carefully what I said about the importance of differential between static and total sag. Also be careful of numbers called out in percentage and in mm. 10/30 is a percentage recommendation (10% static, 30% total). 50mm is what you would wind up with if your rider sag was 25mm and your static sag was 25mm.

eamonnconner, set your preload (sag) and try it all out.