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Discussion Starter #1
Sorry for the long post but if you are a suspension guy or gal please stick with me.... *:)

So I'm getting my bike ready for a trackday next month. *First let me say I've searched. *And searched some more. Then searched again! *I've read all the treads on suspension and sag. I'm not a bike noob but far from an expert. *I've pm'ed a couple of the common posters in the suspension threads. Thanks to everyone for responding back.*

My goal is to set my Enduro mode as a trackday mode for my bike. I don't ride in the dirt and have no use for the current Enduro mode settings. *I've gone in and set the DCT to 3 and engine to 150 high. *Now I want to fine tune the suspension settings and need a little help. *I copied all the Sport suspension settings and applied them in the Enduro mode.*

First, I checked the sag. *I'm 175 without gear. *I have Andrew Trevitts book on sportbike suspension tuning and feel moderately comfortable with the lingo if you will. *When checking sag I had the help of a friend and used the center stand to unweight the rear then front of the bike to get my measurements. *I sat on the bike with gear for my friend to get the 2nd set of measurements. * In Sport mode single rider I ended up with 64mm of sag in the rear with the stock setting at 6. *To get the bike to 50mm of sag in the rear I had to adjust the rear preload to 16. *The front was at 57mm stock and I have not adjusted it as of yet.

Here is where I get confused. *If I have to set the rear preload to the max 16 to get proper sag is that going to compromise optimal suspension since it is maxed out? *I hope I'm on the right track here. *Feel free to correct me if I'm off base.

What are my options? *Anyone care to share their setting after going to the track?
 

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As * long * as * the * sag * is * correct * it * doesn't * matter * if * the * preload * is * set * to * max.

Ok, enough with the **s :p

It's a shame they didn't provide more adjustability so that you can get the sag right for both 1-up and 2-up. Many people are adding a stiffer spring, but I like the way this spring feels so I just want more adjustment range!

PS: I'm about the same weight as the O.P. Is there anyone of the same weight who has added a stiffer spring? Have you noticed much degradation of the "plushness" of the ride on normal urban/country roads? I'm all for increased stiffness on the track but I'd hate to sacrifice the feel on the other 95% of my riding.
 

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Discussion Starter #3
As * long * as * the * sag * is * correct * it * doesn't * matter * if * the * preload * is * set * to * max.

Ok, enough with the **s :p

It's a shame they didn't provide more adjustability so that you can get the sag right for both 1-up and 2-up. Many people are adding a stiffer spring, but I like the way this spring feels so I just want more adjustment range!
:p

Typed it in word.... Copy/paste

I blame the iPad. :p
 

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Oh yeah, remember that adding preload does "consume" stroke range of the shocker, so that's a minus, however for a given weight of rider, you remain the same distance from the "bottom" of the stroke. In the scheme of things, especially on the track, this loss of stroke length is of far less importance than it would be on a dirt trail.
 

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Here is where I get confused. *If I have to set the rear preload to the max 16 to get proper sag is that going to compromise optimal suspension since it is maxed out? *I hope I'm on the right track here. *Feel free to correct me if I'm off base.
The relevance of the adjuster being maxed out is only that you can't add any more.

However, there may be an issue with reaching your preferred laden sag number by adding a lot of preload to a soft spring: the extra preload will eat up your unladen sag. That is, the sag the bike has under just its own weight.

That seems to be a number you have overlooked.

It is about how hard the spring is lifting the bike when the weight comes off it, such as over crests, under brakes, etc.

A heavily preloaded, light spring will want to top out the shock in these conditions. A more lightly preloaded, heavy spring will unload more gently as the shock nears the top of its stroke.

The heavier spring will also offer more resistance to fore-aft pitching as you brake and accelerate. Front too, obviously.

The downside of heavier springs for track use is a less subtle suspension action and ultimately, a bit less grip and feel from the tyres.

A suggestion: measure your unladen sag (sag under bike weight alone). If you've still got 5mm or more at the rear at 16, take her to the track and see how she feels. OTOH, if the unladen sag is barely perceptible at 16, grab the firmer spring first if you can.

A couple of other points:

1. Max on the adjuster does not necessarily mean lots of preload. I think the Ohlins adjuster on those bikes has a range of only 8mm (i.e. at the spring). So it depends a lot on how compressed the spring is at minimum.

2. The sag number is a starting point, not a magic formula. More or less than 50mm rear sag might feel better to you on the track. That is especially relevant for this bike, which has a lot more suspension travel than most race bikes. Running plenty of sag front and rear will lower the bike and might make her feel more secure in turns, while still leaving plenty of bump room for track use.

Disclaimer: I don't own a Multi. (I just like good suspension.)
 

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The relevance of the adjuster being maxed out is only that you can't add any more.

However, there may be an issue with reaching your preferred laden sag number by adding a lot of preload to a soft spring: the extra preload will eat up your unladen sag. That is, the sag the bike has under just its own weight.

That seems to be a number you have overlooked.

It is about how hard the spring is lifting the bike when the weight comes off it, such as over crests, under brakes, etc.

A heavily preloaded, light spring will want to top out the shock in these conditions. A more lightly preloaded, heavy spring will unload more gently as the shock nears the top of its stroke.

The heavier spring will also offer more resistance to fore-aft pitching as you brake and accelerate. Front too, obviously.

The downside of heavier springs for track use is a less subtle suspension action and ultimately, a bit less grip and feel from the tyres.

A suggestion: measure your unladen sag (sag under bike weight alone). If you've still got 5mm or more at the rear at 16, take her to the track and see how she feels. OTOH, if the unladen sag is barely perceptible at 16, grab the firmer spring first if you can.

A couple of other points:

1. Max on the adjuster does not necessarily mean lots of preload. I think the Ohlins adjuster on those bikes has a range of only 8mm (i.e. at the spring). So it depends a lot on how compressed the spring is at minimum.

2. The sag number is a starting point, not a magic formula. More or less than 50mm rear sag might feel better to you on the track. That is especially relevant for this bike, which has a lot more suspension travel than most race bikes. Running plenty of sag front and rear will lower the bike and might make her feel more secure in turns, while still leaving plenty of bump room for track use.

Disclaimer: I don't own a Multi. (I just like good suspension.)
Hi
I have to disagree with some of the above

Mainly unladen sag

This is an irrelevant figure whilst ever you are on the bike track or road.
Hill crests etc still leave unladen sag irrelevant as the whole package rider and bike become light, not just the bike.

Also the rebound on either a light or heavy spring will snap to top out under no load, this is controlled by rebound adjustment, more rebound damping needed by a heavier spring

I have fitted the heavier spring as 2up with luggage I couldn't adjust to a suitable static sag due to preload being maxed, now I can, also I found sport mode was inadequate at best as preload was maxed well before I could get a correct setting, and the standard sport mode used excessive compression and rebound to slow the shock travel giving the false impression of a harder ride.

Plushness of ride can them be dialled in by adjusting rebound and compression.

With the harder spring I am only half way to max preload to get the same touring mode ride I had before, but it let's me stiffen up for my ideal sport setting.

With a soft spring and a heavy rider the multi is using the compression and rebound damping to falsely give the effect of a heavier spring, this is overworking the oil in the shock and can cause premature breakdown.

With a heavier spring the compression and rebound is controlling the spring action as it should not helping it to cope with heavier loads.

For the record I have used expert ohlins guys to set up both my track bike and my multi, I have been lucky enough to understand what they did and have enough knowledge to then fine tune settings for different tracks etc myself

I need to soften up my touring mode settings as overdid it a little when have I will post up my settings for the heavier spring which should give the heavier riders a good starting point should they wish to fit their own heavy spring

Ps: anyone fitting the rear spring themselves it can and should be done with the shock still connected to the electronics etc as even the ohlins guys have had electronics issues after fully removing the shock
 

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The downside of heavier springs for track use is a less subtle suspension action and ultimately, a bit less grip and feel from the tyres.


This again sorry I have to disagree, the suspension action is more controlled as the heavier bike/rider package is within the heavier springs capabilities, the softer spring relies on excessive damping and preload to control weights outside it's abilities.

So a Heavy spring can be set up much more accurately when a heavier rider is on the bike as the damping and compression is being used to correctly control the spring not to help it cope with a bike/rider combination outside it's capabilities
 

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One final ps: to this

Static sag should be set up with rider on the bike both wheels on the ground no centre or side stand

To do this on your own use a tie wrap around the fork slider or shock centre rod, push them to the top then climb on, do not bounce the bike, climb off and measure the front with no load on the front, then measure the rear no load on the rear.

Adjust preload and repeat until correct measurements are achieved

I also leave the tie wrap on during track days as it let's me check how much suspension travel is being used, another rule of thumb is that you should b using all but.10mm of travel n the front and all but 5mm on the rear.

If during track use or very heavy road use the tie wrap is hitting the bottom of the fork slider then you need a little more preload and compression damping, you will be surprised how little so adjust in small amounts and retry
 

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Hi
For the record I have used expert ohlins guys to set up both my track bike and my multi, I have been lucky enough to understand what they did and have enough knowledge to then fine tune settings for different tracks etc myself

... will post up my settings for the heavier spring which should give the heavier riders a good starting point should they wish to fit their own heavy spring
Please do post. I'm very interested in your settings. Thanks, Mark
 

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One final ps: to this

Static sag should be set up with rider on the bike both wheels on the ground no centre or side stand

To do this on your own use a tie wrap around the fork slider or shock centre rod, push them to the top then climb on, do not bounce the bike, climb off and measure the front with no load on the front, then measure the rear no load on the rear.

Adjust preload and repeat until correct measurements are achieved

I also leave the tie wrap on during track days as it let's me check how much suspension travel is being used, another rule of thumb is that you should b using all but.10mm of travel n the front and all but 5mm on the rear.

If during track use or very heavy road use the tie wrap is hitting the bottom of the fork slider then you need a little more preload and compression damping, you will be surprised how little so adjust in small amounts and retry

I assume you mean static is no rider, and rider sag is as described in first sentence. That is how I/we all my suspension gurus lindeman race tech etc did my road race and dirt bikes.
I am at a bit of a loss with the fact I need no tools with the multi 1200s I just bought. :surprise::wink2:
 

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I have to disagree with some of the above

Mainly unladen sag

This is an irrelevant figure whilst ever you are on the bike track or road.
Hill crests etc still leave unladen sag irrelevant as the whole package rider and bike become light, not just the bike.
Knowing the "free" or "unladen" sag can help determine whether you're using the correct springs. On a typical sport bike with 120mm (4.7") of suspension travel, free sag should be around 5mm (~3/16"). If free sag is close to zero, you might benefit from using a stiffer spring. If you've got too much free sag, you may benefit from a softer spring. The Multistrada has longer-travel suspension, so slightly more free sag may be appropriate for us?

Plushness of ride can them be dialled in by adjusting rebound and compression.
Compression and rebound damping work best when you've got a spring rate that's optimal for your weight.

Imagine you had a spring that was either way too light (say, a coiled up coat hanger) or way too heavy (say, a solid iron bar). In both of those cases, the inadequacy of the spring will overcome any benefits that compression and rebound damping provide. If the spring is way too heavy, the suspension won't move and so neither compression not rebound damping will come into play. If the spring is way too light, the suspension will be moving so often and with such velocity that the damping won't be able to compensate.

You won't encounter conditions this extreme on a motorcycle, but the point remains: if your spring rates are way off, you won't be able to use damping to compensate for the problem.
 

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Knowing the "free" or "unladen" sag can help determine whether you're using the correct springs. On a typical sport bike with 120mm (4.7") of suspension travel, free sag should be around 5mm (~3/16"). If free sag is close to zero, you might benefit from using a stiffer spring. If you've got too much free sag, you may benefit from a softer spring. The Multistrada has longer-travel suspension, so slightly more free sag may be appropriate for us?



Compression and rebound damping work best when you've got a spring rate that's optimal for your weight.

Imagine you had a spring that was either way too light (say, a coiled up coat hanger) or way too heavy (say, a solid iron bar). In both of those cases, the inadequacy of the spring will overcome any benefits that compression and rebound damping provide. If the spring is way too heavy, the suspension won't move and so neither compression not rebound damping will come into play. If the spring is way too light, the suspension will be moving so often and with such velocity that the damping won't be able to compensate.

You won't encounter conditions this extreme on a motorcycle, but the point remains: if your spring rates are way off, you won't be able to use damping to compensate for the problem.
Great summary...

I'm struggling here with the multi... I know I need more rear spring (either that or less beer and more exercise to get my weight under 200lbs) but there are really no options for the DVT that match (that I'm aware of) the dual rate characteristics of the stock spring at higher rates. I could go with a single rate spring and give up some of the touring comfort to get the spring rate where it needs to be, but that's sub-optimal for a bike that spends much of its time in touring mode.

I suspect that eventually there will be enough DVT's on the road to get a custom spring made for those of us in the 225lb range... but while the pre-15's have had a group buy pretty recently, it hasn't happened yet for the DVT bikes. So up to now I've taken a rough swag at sag... but I'm not putting effort into getting it dialed in because I know the spring is a problem.
 

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I suspect that eventually there will be enough DVT's on the road to get a custom spring made for those of us in the 225lb range... but while the pre-15's have had a group buy pretty recently, it hasn't happened yet for the DVT bikes. So up to now I've taken a rough swag at sag... but I'm not putting effort into getting it dialed in because I know the spring is a problem.
One great remedy I found for my Multitrada was buying the Ohlins Semi Active ECU. That way I dont have to do anything! Oh wait.... never-mind, carry on :|
 

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One great remedy I found for my Multitrada was buying the Ohlins Semi Active ECU. That way I dont have to do anything! Oh wait.... never-mind, carry on :|
My preload adjustment DOES help a lot... but I'd prefer to have the preload adjusting just a bit rather than having to be at "rider and luggage" (quite a bit of preload) to get the suspension near where it should be with my ass in the seat.
 

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I've got the upgraded suspension ECU, and will bump the preload to rider w/ luggage when I hit the curvy roads. I'm 165lbs with gear, and this setting works for me. Of course, these days I'm not as fast as I used to think I was...:rolleyes:
 

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I've got the upgraded suspension ECU, and will bump the preload to rider w/ luggage when I hit the curvy roads. I'm 165lbs with gear, and this setting works for me. Of course, these days I'm not as fast as I used to think I was...:rolleyes:
I weigh just under 220 so my preload is about 12 or so. I think max is 16? Cant be too sure. But yeah, I ride with some decent preload on single with luggage in the tight stuff and single just maybe 9 I think which is comfy for me.
 
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