Ducati Monster Forum

Moto Board => Tech => Topic started by: WhiteStripe on April 04, 2011, 08:45:20 AM

Title: Suspension tweaks for a begginer??
Post by: WhiteStripe on April 04, 2011, 08:45:20 AM
I know this is an oft discussed topic, and have read the great FAQ write-up, but i am a little daunted by tweaking my suspension.

I am an avid mountain biker and mess with my suspension all the time, so I get the general concepts of dampening and rebound etc., but somehow on my Monster i wam worried about messing something up - and the need for suspension is a very differnt animal (big hits vs. cornering)

I have a 2006 S2R1000.  I am 6.0' tall and weight 185 - 190.  I have decent tools and some mechanical ability.

I feel like (1) the bike is too low, (2) the rear shock sag is too much, and (3) the whole setup is too soft (which woudl make sense based on my weight).

Does anyone want to recommend some changes that I can experiment with that do not require the investment of several weekends and that won't make the bike unrideable/unsafe.

Alternatively, feel free to tell me i am an idiot and that i should pay someone else to do it.  SUggestions on that welcome as well.

Tim
Title: Re: Suspension tweaks for a begginer??
Post by: hackers2r on April 04, 2011, 09:03:57 AM
Well you're probably going to want to replace the front and rear springs for something your weight.  You may be able to add some preload front and rear to get the sag numbers closer to the proper range.  Are the fork tubes pretty much flush with the triple clamps?  Did you buy the bike new?  If the fork tubes have been slid up in the triple, you can pull them back down which will raise the bike.  Also, you can increase ride height in the rear to bring the bike higher.  Be aware though, that if you raise the rear independently of the front, the bike will turn more quickly.  Not necessarily a bad thing but just wanted you to be conscious of the result.
Title: Re: Suspension tweaks for a begginer??
Post by: Slide Panda on April 04, 2011, 09:27:30 AM
I'll lean towards paying someone. Ideally, you would find someone who is willing to instruct you on the why and wherefore of what they are doing. 
Title: Re: Suspension tweaks for a begginer??
Post by: WhiteStripe on April 04, 2011, 10:19:08 AM
Quote from: hackers2r on April 04, 2011, 09:03:57 AM
Well you're probably going to want to replace the front and rear springs for something your weight.  You may be able to add some preload front and rear to get the sag numbers closer to the proper range.  Are the fork tubes pretty much flush with the triple clamps?  Did you buy the bike new?  If the fork tubes have been slid up in the triple, you can pull them back down which will raise the bike.  Also, you can increase ride height in the rear to bring the bike higher.  Be aware though, that if you raise the rear independently of the front, the bike will turn more quickly.  Not necessarily a bad thing but just wanted you to be conscious of the result.

I bought the bike from a close friend, nothing has been touched.  I *understand* the issue with raising just the rear, whcih is why i am hesitant to mess with that.  DIdn't even think that raising the fork tubes might be possible.


My inclination was to add preload front and rear, which i figured woudl reduce sag and make everything a bit stiffer, assume that this comes at the expense of some bounciness without some dampening adjsutment?
Title: Re: Suspension tweaks for a begginer??
Post by: hackers2r on April 04, 2011, 10:27:09 AM
Well the only way you could have raised the front was if someone had lowered it.  If not, leave it as is.  Yes...when adding preload, you need to compensate with adding rebound damping.  I would try to get the sag and rebound figured out and then see how it handles for you.  If you still want it higher, you can raise the rear. 
Title: Re: Suspension tweaks for a begginer??
Post by: bikepilot on April 04, 2011, 04:01:03 PM
I'm all for fiddling with your own suspension.  I find it really worthwhile to develop an understanding of how it works.  You can pay someone, but they won't know exactly how you ride and what you like and you probably won't want to pay them to continually tweak it depending on where you are riding, temp etc.  Of course they'll get it a lot closer than it is now.

Don't worry too much about botching it.  Just write down the settings where its at now and you can always go back.  Without modifying the bike its nearly impossible to make the bike truly dangerous on accident.

For starters set the sag front and rear.  This may require stiffer springs.  As a general rule of thumb you want about 10mm of free sag and 25mm of race sag.  Since you are on the slightly-heavier-than-average side you'll probably want a little more damping to go with the extra preload and/or stiffer springs it'll take to get that sag.  Add a click of compression and two clicks of rebound (if your bike has both adjustments, I haven't played with an s2r) for starters. 
Title: Re: Suspension tweaks for a begginer??
Post by: Gimpy on April 04, 2011, 10:38:29 PM
I wished I would have started with correct springs when I went down this path.  I messed around with the compression/rebound/preload settings for a long time before finally spending the money.  It always seemed a little different but never what I wanted.  Always kinda differently wrong. 

Once I replaced the rear shock and spring, changing the settings began to make sense.  I was very quick to upgrade the stock springs in the forks after that.  Now I'm way more confident when I make an adjustment to my suspension.  Its much easier to feel the difference now that I have a good starting point.
Title: Re: Suspension tweaks for a begginer??
Post by: WhiteStripe on April 05, 2011, 06:13:07 AM
Quote from: bikepilot on April 04, 2011, 04:01:03 PM
Don't worry too much about botching it.  Just write down the settings where its at now and you can always go back.  Without modifying the bike its nearly impossible to make the bike truly dangerous on accident.

For starters set the sag front and rear.  This may require stiffer springs.  As a general rule of thumb you want about 10mm of free sag and 25mm of race sag.  Since you are on the slightly-heavier-than-average side you'll probably want a little more damping to go with the extra preload and/or stiffer springs it'll take to get that sag.  Add a click of compression and two clicks of rebound (if your bike has both adjustments, I haven't played with an s2r) for starters. 
Thanks this is helpful - in line with waht i have been thinking - giving me a little more confidence that i actually know enough to be dangerous (or not dangerous...).

QuoteI wished I would have started with correct springs when I went down this path.  I messed around with the compression/rebound/preload settings for a long time before finally spending the money.  It always seemed a little different but never what I wanted.  Always kinda differently wrong.

I know this is the right path at my weight (honestly i am not fat...).  Any suggestions where I shoudl start researching new springs etc.  Any personal suggestions?

Thanks for the information.



Title: Re: Suspension tweaks for a begginer??
Post by: hackers2r on April 05, 2011, 07:00:33 AM
You can give any of the suspension companies a call and they'll give you the correct spring rates.  Ohlins, GP Suspension, etc.  They'll also have the correct springs for you.  They may also suggest changing out the oil in the forks.  How many miles are on the bike?  Since you've done suspension work before, although on bikes, you shouldn't be in over your head with this.  Plus, if you have any questions, you can ask us here! 
Title: Re: Suspension tweaks for a begginer??
Post by: bikepilot on April 05, 2011, 08:16:38 AM
For spring rates, you'll know how far off you are (if any) when you try and set sag.  If you have too little free sag when race sag is correct the springs are too soft and vice versa. This won't get you absolutely exactly at the optimal point, but you'll be reasonably close in terms of correct spring rate if you are able to get both race and free sag correct at the same time.
Title: Re: Suspension tweaks for a begginer??
Post by: Meerkat on April 05, 2011, 01:33:56 PM
Quote from: hackers2r on April 05, 2011, 07:00:33 AM
They may also suggest changing out the oil in the forks.
Took the total control class this weekend and during our suspension section it was recommended to change the fork oil every other season. Stuff gets nasty and loses the appropriate viscosity.
Title: Re: Suspension tweaks for a begginer??
Post by: WhiteStripe on April 05, 2011, 03:31:02 PM
Quote from: hackers2r on April 05, 2011, 07:00:33 AM
You can give any of the suspension companies a call and they'll give you the correct spring rates.  Ohlins, GP Suspension, etc.  They'll also have the correct springs for you.  They may also suggest changing out the oil in the forks.  How many miles are on the bike?  Since you've done suspension work before, although on bikes, you shouldn't be in over your head with this.  Plus, if you have any questions, you can ask us here! 
Thanks so much.  the bike is about 5k miles.  Think i am going to start by messing with the SAG and then will head down the path of springs.

Appreciate all the input for such an overdiscussed topic!
Title: Re: Suspension tweaks for a begginer??
Post by: bikepilot on April 06, 2011, 08:03:31 AM
I generally shoot to change fork and shock oil every season (sometimes slack and don't though if I'm not pushing the really hard/racing).  Just part of regular maintenance on anything with serviceable suspension.  Stick with the same brand oil as even for a stated weight different brands differ a little in actual viscosity and it'll play havoc with your suspension settings.  Doesn't matter too much what you chose, just use the same stuff over and over.  I tend to buy a case of oil at a time so I've got a bunch to last a little while and don't have to worry about finding the same stuff again the next year.

Title: Re: Suspension tweaks for a begginer??
Post by: Amlethae on April 07, 2011, 07:17:23 PM
Great stuff in this thread.  I'm on the opposite side of things kinda... I don't know shit all about suspension adjustments and I only weigh about 125lbs.  And I'm only 5'8" so on my 1100S I did recently back off the pre-load from stock to the point where I can just barely flat foot it and I'm still 1/2" inside of the "maximum recommended spring length".  But should I be adjusting other settings as well? 

Also: is there a book or website or something that explains (in general) all the suspension settings for bikes, what they do, and what needs to be adjusted as a result of adjusting something else? 

Thanks!
Title: Re: Suspension tweaks for a begginer??
Post by: hackers2r on April 08, 2011, 07:01:22 AM
Hmm...not sure how much sag there is if it changed the ability to flat foot-edness but I'd be willing to bet it's too much.  Check out this page for help setting up the suspension.  http://www.ohlins.com/Checkpoint-Ohlins/Setting-Up-Your-Bike/Underrubrik_1/ (http://www.ohlins.com/Checkpoint-Ohlins/Setting-Up-Your-Bike/Underrubrik_1/)  When you add damping to the compression or rebound, it slows down that action.  So if you add compression damping, it will slow down the shock compressing.  That page should help you get a good starting point.
Title: Re: Suspension tweaks for a begginer??
Post by: Amlethae on April 08, 2011, 08:23:12 AM
I really should check the sag on it.  I however don't have a good way to lift the rear tire/bike off the ground to check that sag point before loading it.  Is there some half-assed way around this?  Or some recommendation of how to do it?
Title: Re: Suspension tweaks for a begginer??
Post by: hackers2r on April 08, 2011, 08:30:49 AM
Well if you have a buddy, you can usually lift the front and rear yourself in order to extend the suspension while they measure.  The  bike's wheels don't have to leave the ground, the suspension just needs to be unloaded.  You'll probably be able to feel this point if you're doing the lifting.  It will get VERY heavy all of a sudden.