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bugjuice
21st December 2005, 11:21
Ok, the mother of all topics. Covered a million times, I know, but it's one of the most important issues of most of our machines, right next to 'what type of air should I put in my tyres...'

Has anyone got any 'gold' links for setting up suspension? Has anyone tried the settings suggested on the Sportrider.com (http://www.sportrider.com/bikes/146_susp_settings/) site? Or are there any better formulas? (don't forget to write down the settings before you do this tho, so you can go back!)

I've got a couple of weeks off, so I'm thinking about setting my bike up as per info from this site, and see how the bike feels after that for a few runs. Just wanted to ask, to see if anyone has thought about this side of the bike properly? Hell, you don't know that you've got a bad handling bike, until you make it handle properly...

Grahameeboy
21st December 2005, 11:34
Ok, the mother of all topics. Covered a million times, I know, but it's one of the most important issues of most of our machines, right next to 'what type of air should I put in my tyres...'

Has anyone got any 'gold' links for setting up suspension? Has anyone tried the settings suggested on the Sportrider.com (http://www.sportrider.com/bikes/146_susp_settings/) site? Or are there any better formulas? (don't forget to write down the settings before you do this tho, so you can go back!)

I've got a couple of weeks off, so I'm thinking about setting my bike up as per info from this site, and see how the bike feels after that for a few runs. Just wanted to ask, to see if anyone has thought about this side of the bike properly? Hell, you don't know that you've got a bad handling bike, until you make it handle properly...

I tried the setting on my SV1000S and the settings are not much different to standard.......didn't feel too good so went back to standard.

Eg, they recommend 6 rings on front which is standard and I have mine on just 4 which I found worked on my RF900 well too.....I weigh 100kg so Craig at Colemans put an Ohlins spring on my old RF to keep ride height etc

You are on North Shore and the guy at Cycletreads told me that he would do mine for $50..seems the SV can do with some more rear pre load but no tools....I will try him and see how bike is....

Fishy
21st December 2005, 11:38
I set up my 04 Blade from the sportrider website and it is bloody awesome!!! made it feel like a different bike! Highly recommend it.

Sensei
21st December 2005, 12:27
What is it doing or not doing Bug ?

Lou Girardin
21st December 2005, 12:42
Unles the rider is the same weight as you, and rides the same type of roads at the same speeds as you, you'll be better off setting it up from scratch. Set the static and rider sag. Then adjust the damping to suit.
There's been plenty of posts on the subject.

bugjuice
21st December 2005, 13:17
What is it doing or not doing Bug ?
I'm not sure.. just feels like there's more to unlock. And knowing I haven't really played much with it, I know I'm just riding it and pushing it 'as is'. On the track day at Taupo, I think it could have been better set up, but I'm only a pro at making things worse, so wasn't sure on playing with it. It handles well, I just think it could handle better, and I'm keen to start playing with things like that now..

And Lou, I know there's been a few topics on this, and I'm going thru them bit by bit, but I wanted to know lately, if anyone has tried the suggested settings or if there's anything better out there.

What I don't like about that link, is that there's no rider info, and doesn't say if it's set up for the track or open road etc. And I've heard mixed things about someone else setting up your bike. If it's set for one person, might not be right for another. Plus, what if that persons' prefs are different from yours? You could ride Rossi's bike, and only say it's good, cos he rides it..

vifferman
21st December 2005, 13:32
I tried the SportRIder settings when I had the VTR1000. They gave me a harsh ride.
I suspect their recommendations are track-biased, and probably for lard-arsed Murkns.
Still, at least it was a starting point. As were the 'factory' settings I reverted to, which ended up closer to what I found was best for me.
For the VFR, I just set static sag, and adjust the preload and damping on the rear by one click when the vifferbabe's co-piloting.

bugjuice
21st December 2005, 13:36
Just stumbled across something 'Raven' found and posted, about setting up suspension. Looks like it got over-looked by me!

Part 1 (http://www.kiwibiker.co.nz/forums/showthread.php?t=20508)
Part 2 (http://www.kiwibiker.co.nz/forums/showthread.php?t=20510)
Part 3 (http://www.kiwibiker.co.nz/forums/showthread.php?t=20511)

Even reading this, I'm still eager to find out as much info as I can, and settings to try etc..

**R1**
21st December 2005, 13:39
Unles the rider is the same weight as you, and rides the same type of roads at the same speeds as you, you'll be better off setting it up from scratch. Set the static and rider sag. Then adjust the damping to suit.
There's been plenty of posts on the subject.exactly, you need to set it up for you, and the roads ya riding, and i wouldnt go setting it up for the track unless thats where you will be doing the majority of ya riding, but if ya like me and spend 99% of the time on the road then the last thing ya wana do is set it up for the track.....my 2c worth

bugjuice
21st December 2005, 13:56
ok, so just read the 3 parts that I linked. It's a great guide to setting up bike and rider sag, so I'd recommend everyone start there.

So now it's just compression, rebound and damper rates to figure what's best. Plus with the ZX6, they rolled them out on 65 profile tyres, but now I have 70s. It feels better now than before (imo), and some say leave it, a lot say drop the forks.. I'll try dropping them (after this time on the same setting) and see how much better it is.

cowpoos
21st December 2005, 14:00
I'm not sure.. just feels like there's more to unlock. And knowing I haven't really played much with it, I know I'm just riding it and pushing it 'as is'. On the track day at Taupo, I think it could have been better set up, but I'm only a pro at making things worse, so wasn't sure on playing with it. It handles well, I just think it could handle better, and I'm keen to start playing with things like that now..

And Lou, I know there's been a few topics on this, and I'm going thru them bit by bit, but I wanted to know lately, if anyone has tried the suggested settings or if there's anything better out there.

What I don't like about that link, is that there's no rider info, and doesn't say if it's set up for the track or open road etc. And I've heard mixed things about someone else setting up your bike. If it's set for one person, might not be right for another. Plus, what if that persons' prefs are different from yours? You could ride Rossi's bike, and only say it's good, cos he rides it..

set your sag as perfectly as possible....then come back to this thread and ask more questions....your bike will never handle near its potential until the sag is set for you and your weight.....

cowpoos
21st December 2005, 14:03
ok, so just read the 3 parts that I linked. It's a great guide to setting up bike and rider sag, so I'd recommend everyone start there.

So now it's just compression, rebound and damper rates to figure what's best. Plus with the ZX6, they rolled them out on 65 profile tyres, but now I have 70s. It feels better now than before (imo), and some say leave it, a lot say drop the forks.. I'll try dropping them (after this time on the same setting) and see how much better it is.

better to lift the rear 5mm...other wise your going to be changing the swingarms angle by dropping the forks...I think you can lift the rear using shims on zx6

bugjuice
21st December 2005, 14:09
lift the rear? k, first one to suggest that..
but if the back is fine, then surely you'd leave it? The change is to the front tyre..

Also, is there a 'rule-of-thumb' for sag? The links suggest for bike sag 'The rear sag should be somewhere between zero and 10 millimetres and the front between 20 and 30 millimetres.' And the rider sag 'should fall somewhere in the vicinity of 25-35mm front and rear'. Is that about right for a sprotsbike?

I know that cruisers would differ from sprots to dirt to motard to classics etc etc.. I'm not fussed about those ;)


also noticed on the sprotsrider.com link I posted, it mentions nothing about sag, so if I set up the sag for me, then tried these settings, that'd be an ok place to start, ay?

Sensei
21st December 2005, 18:18
Have found from setting up my own bike's that you do 1 thing at a time so as not to confuse yourself with what has or has not worked .Write down your changes in a book to as you can go back to this later .

Brian d marge
21st December 2005, 18:52
set your sag as perfectly as possible....then come back to this thread and ask more questions....your bike will never handle near its potential until the sag is set for you and your weight.....

agreed on that one, If you dont have the correct spring rates , for your wieght . All of the other setting are just wasting time.

Spring rate , linkages working as thy should be, sag set( that percent rule of thumb is a bit of a sledge hammer, sag , or the amount the springs have to deal with topping out , is adjustable for the conditions ,,,etc )

Then you can dial the rebound and compressions and ride heights .......

the clickers are a fine tune, if you think of a piece of string with one end fully soft and the other fully hard , the factory settings are in the middle , the clickers adjust say 10 percent of the middle ...

I dont have the info to hand ..so this is from top of head and prone to operator error ....

but

ya cant avoid the springs,,,,been there done that.....saw arse go past ears ...on many occasion .....


Stephen

TwoSeven
21st December 2005, 19:16
Which sag is everyone on about, unladen, laden, or static ?

cowpoos
21st December 2005, 19:48
Which sag is everyone on about, unladen, laden, or static ?

unladen is static....rider sag is the best comprimise if springs are light....buggy ain't the biggest lad so he'll probally get pretty close on the standard spring....to getting the right rider and static sag

cowpoos
21st December 2005, 20:09
lift the rear? k, first one to suggest that..
but if the back is fine, then surely you'd leave it? The change is to the front tyre..

Also, is there a 'rule-of-thumb' for sag? The links suggest for bike sag 'The rear sag should be somewhere between zero and 10 millimetres and the front between 20 and 30 millimetres.' And the rider sag 'should fall somewhere in the vicinity of 25-35mm front and rear'. Is that about right for a sprotsbike?


when you increased the front tyre profile you effectivly lifted the front 5mm...and lessened the swingarm angle in the process....if you drop the forks through the yokes...you will lose ground clearence...if you lift the rear you will gain it...and by doing that you will make more use of the width of your front tyre...even though most people get rid of the chicken strips on there rear tyres most of them still have them on the front tyre....that tells you...that you have even more lean angle to use up...
http://www.gostar-racing.com/information/motorcycle_suspension_set-up.htm

that should set u on the right path

I really think the biggest question is....what is your bike doing that you don't like???? and if you don't know [don't take this the wrong way] its probally because your bike is more than capable of handling your riding ability as it is right now...could be worth while possibly focusing on improving your riding and at some stage it might start to show up weak-nesses in your bikes handling...

but if your heart is set on playing with your bikes handling.... buy this http://www.traxxion.com/store/detail.asp?product_id=SUS4V its avalible from robert taylor in hawera 06 2784160

bugjuice
21st December 2005, 20:50
that link to the vid is pretty cool.

As for what my bike is doing that I don't like, it's too harsh. I feel I can push the bike a bit more, but it feels every bump in the road, and the front just skips like hell. It's still pretty much factory set, so I know it isn't set for me. I'll try setting the sag as what that other link mentions and see what sort of difference that makes in the handling.

Ideally, I wanted to try this at the track. Have the bike out at what it is now, then reset the sag and work from there, doing a session on each new setting. I've ridden the bike for over a year set how it is now, and I'm starting to get to the point where it's too skitish, and I've not touched the set up really. So if I can make the bike handle better, I can then progress my skills a bit more.. or so me thinkin goes.. I just don't want to make an 'ok' handling bike, crap. I'd rather make it better..

cowpoos
21st December 2005, 21:38
that link to the vid is pretty cool.

As for what my bike is doing that I don't like, it's too harsh. I feel I can push the bike a bit more, but it feels every bump in the road, and the front just skips like hell. It's still pretty much factory set, so I know it isn't set for me. I'll try setting the sag as what that other link mentions and see what sort of difference that makes in the handling.

Ideally, I wanted to try this at the track. Have the bike out at what it is now, then reset the sag and work from there, doing a session on each new setting. I've ridden the bike for over a year set how it is now, and I'm starting to get to the point where it's too skitish, and I've not touched the set up really. So if I can make the bike handle better, I can then progress my skills a bit more.. or so me thinkin goes.. I just don't want to make an 'ok' handling bike, crap. I'd rather make it better..

when you ring up robert about that vid....if you do...tell him what you just said about how your bike behaves.....he will have the right answer for you...as he knows more about suspension than anyone else in the country...they don't call him DR robert for nothing

Brian d marge
22nd December 2005, 00:26
Go to Dr Taylor, or tjebe briun or who ever. BUT go prepared,

Get a good section of road .with ripples on the racing line..( easy on a mx track)
Mark the ideal racing line. ( floro paint !!!!:wavey:to transit NZ ... Now go through the line at a slower speed . with someone video taping you so that you can see both suspension working AND the ideal line markers,

Now do the same but faster,( without changing the suspension settings ...*they should be set at factory or as close to the ideal sag as you can get ...without using to much preload ... you will find the bike tucks in /drifts out , this is the compression/rebound setting relationship between front and rear.
* eg, if the rebound is to soft you will unload the front and the front will drift out towards the outside of the corner *

The short story is if you show this tape to a suspension tuner , they will be able to set up your bike More accurately , than if you just turned up and said the bike feels harsh.

I did this with my MX bike and I SAW and realized what was going on with my bike ( it had been valved for a light rider and I am a fat bastard, so the rebound _ on the front _ needed two 0.2 shims on the rebound valve .
Along with the video
take your weight WITH riding gear, And a realistic comparison to a well known racer... ( or any comparison that will give him a idea of your riding style, experience )

You should get back a bike that will only need a few clicks either way on the adjusters , to get it feeling sweet ....

Well worth the money and time invested ......

BTW What bike and what wieghts are we talking about


Stephen

R1madness
22nd December 2005, 09:17
Forget all that crap. Write down what the current settings are. Fiddle with the knobs one at a time and see what the bike does. Does it run wide on the exit? Does it turn in faster or slower? When you open the throttle does it sink badly in the rear? Does it wheelstand more/easier on the gas? Do you want that? Is it harsh over the bumps? Does it shake its head more on the gas? Do you care? Does it feel better on the front end under brakes? Is it bouncy? Does it feel better?
You will feel the difference in a few corners if you pick a bit of road or track you know well and do the adjustments on the side of the road.
The funny thing is what feels better is not necessarly faster. the stopwatch tells the truth where riders lie.
Did you know that when Arron Slight and Colin Edwards both ran RC45s they ran totaly opposite suspension settings? What matters is that the suspension suits your riding style, not some magical number that suits the average rider on the average condition new bike on the average road or track. Too many averages.......

Lou Girardin
22nd December 2005, 10:38
better to lift the rear 5mm...other wise your going to be changing the swingarms angle by dropping the forks...I think you can lift the rear using shims on zx6


Other way round. Raising the rear ride height alters the swing arm angle and can cause traction problems accelerating out of corners. This is from the gospel according to Ohlins.

Ducman
22nd December 2005, 10:51
I raised the rear 8mm on my ZX6R G1. It has the effect of putting more weight over the front, and can help with drive out of the corner, just like dropping the forks only your not sacrificing ground clearance

bugjuice
22nd December 2005, 10:53
lol.. gotta love gospel stuff.. but yeah, I haven't heard of raising the back, it's always been to drop the front back to the height that it would be with a stock tyre. Other wise, you'd have lifted the whole bike, instead of adjusting back to stock height.

R1M - as for what the bike is doing, the ride is feeling harsh. I've put up with it and adapted my riding style to suit the bike. But I've never pushed any other bike like I push mine, so I have no idea if it's the crappest handling bike in the world (it couldn't be, cos there's not a lot that bike could do wrong ;)). When I'm taking corners, if I run wide or shallow, I just adjust it. Cos I've got no other bike experience other than this bike, I can't say if it's the bikes' fault or mine. I just adjust to the condition and deal with it. Not saying that I'm a crap rider, or the bike is crap, just saying that so far, I've just dealt with it and rode to the conditions. But now I feel there there's a bit more to unlock in me and the bike. Everyone who's bought an 03/04 ZX6 has said the ride is too solid. Well now I have stepped up my game, the bike is broke in well, and the settings are all stock, I feel it's time to start looking at more technical things to help improve my game, and the bikes' ability. I'll start with setting the sag properly (this I've never done, but read on doing it, so can't be too hard), and then from there, I'll have a look at what other people have posted their settings for the bike and their details (rider height and weight, road conditions, tyres) and get a 'general' setting for my bike, then I can start to refine it to me more.

When I was at the track, I got a few tyre spins out of exits (I know, tyres cold? no. Too much power down? probably. Crap on the track? most likely), the front gets real twitchy under power, which I know - it's a powerful bike, so it will, but I've heard a few pros say that dampers are often over-rated, and should only be fitted after the suspension has been set up. I can't afford a decent damper at the moment, but toying with the settings are free. I've had more slappers than a decent night on K'rd, which I enjoy now, and deal with, but round corners, I feel I have to back off a bit, instead of pushing it thru, cos the front feels too hard. I'm not using the full length of the forks either (well, rarely do). The brakes are cooking (which I was told by a few, is a partial result of the suspension not being right), and just over all, the bike feels harder than other bikes I've sat on.

I've gone this long, and I can't afford more toys to stick on it at the moment, and it's never been set, so I want to do it, and do it the right way (not get it right cos that takes time), so that I can gain some more confidence, and just better my abilities on the bike. I know there's no magic number someone has just for me, but I need something to start on. So I'll try those sag settings unless anyone else has any better facts n figures, and go from there..

Ducman
22nd December 2005, 10:54
I guess it depends on the origional geometry of the bike.. raising the rear made a huge improvment on my bike

cowpoos
22nd December 2005, 10:59
Other way round. Raising the rear ride height alters the swing arm angle and can cause traction problems accelerating out of corners. This is from the gospel according to Ohlins.

he has fitted a high profile front tyre...by 5mm

bugjuice
22nd December 2005, 11:07
yeah, which would raise the front by around ~5mm (at new, the tyre is worn now), so by dropping the forks back down ~5mm, it'd theoretically bring the front of the bike back down to the stock height. Only diff, is it's change the rake by something like 0.005°

Lou Girardin
22nd December 2005, 11:19
I think Ohlins is refering to the swing arm angle in relation to the frame of the bike, not to ground level.
If you increase the angle by raising ride height, which is lengthening the shocks overall length, torque reaction on the swingarm is increased due to the increased angle and this effectively stiffens the rear susp under acceleration.
At least that's how it sounded to me.

2_SL0
22nd December 2005, 11:42
I am far from qualified to help but I will tell what I have done to mine. I set the rear sag for my weight. Its a simple task, it made a dramatic difference to how my bike felt. I touched nothing else for a month or so. Then I took the bike out to a piece of road I know well. I adjusted one setting fully one way. Took the bike for spin. Adjusted the setting fully the other way, again took the bike for a spin. That gave me a very clear picture of what that adjustment did. I then used the factory setting as my start point and adjusted from that. I also did a lot of reading on the subject. But I dont ride my bike anywhere near what its capabilities are, when I reach that point the setting will require adjustment again no doubt.

bugjuice
22nd December 2005, 11:46
yeah, I think that's what I'll end up doing.. I'll set the sag, then everything half way-ish (still thinking about dropping the forks), and take note of the settings everyone seems to have, and then do a stretch like Old North Road. Do a run with them half way, then one on full, then may be one on soft, and then see where things lie. And compare them to what other people have set.

My bike has done nearly 22,000ks now too, so it'll be nicely broke in to start playing with things like this

pritch
22nd December 2005, 12:14
The Ohlins website has pdf files available for download including an "Owners Manual". The detailed info relates specifically to Ohlins, of course, but the step by step setup proceedure and sequence is spelled out and probably applies equally to any brand of shock.

bugjuice
22nd December 2005, 12:33
cheers pritch..

just checked up their website and found this, which I'll have a read thru: http://ohlins.com/mc_ultimate_tuning.shtml
and a PDF (on another page) of their tuning guide. http://ohlins.com/pdf/07255-01.pdf

Brian d marge
22nd December 2005, 13:15
Forget all that crap. .

Why????

Why do you think teams fit telemetry to bikes ??? so they can fiddle with a few adjusters ( that will only change the fork action a few percent ????)

I for one cant afford telemetry, and there NO way I can tell the difference between settings on a poorly set up bike ( for the record when I fitted my front end it had been valved for a proffesional, who weighed 70 to 80 kg...sags ok but rebound shim stack ...way off... would kick up on the jump face ) So NO amount of clicker settings would cure it ,,I could notice the difference between 8 or more clicks either way ...just ,,the rest of the time I was hanging on for dear life with the front popping out of the ruts on corners , which tended to high side ,,,,

So I had a email session with Jeremy wilkey , MX Tech ,,,and thats what was suggested to me ..and it worked you can see what is happening to the forks , how the bike wasnt getting traction ....

Still whole lot easier to twist a few clickers and change the oil ... :corn:

Stephen

cowpoos
22nd December 2005, 13:24
I think Ohlins is refering to the swing arm angle in relation to the frame of the bike, not to ground level.
If you increase the angle by raising ride height, which is lengthening the shocks overall length, torque reaction on the swingarm is increased due to the increased angle and this effectively stiffens the rear susp under acceleration.
At least that's how it sounded to me.

due to the fact that the bike in question runs a linkage...droping the forks through the yokes will soften the rear end....lifting the rear will infact get the bike back to dam near [+/- .05 degree] the way the digresive linkage should actituate [speeling]...the reason why most people sugest droping the forks through the yokes is because its the easyest and cheapest...buying some shims and having them fitted is still alot cheaper than replacing the linkage arm to an adjustable one...

Lou Girardin
22nd December 2005, 14:47
due to the fact that the bike in question runs a linkage...droping the forks through the yokes will soften the rear end....lifting the rear will infact get the bike back to dam near [+/- .05 degree] the way the digresive linkage should actituate [speeling]...the reason why most people sugest droping the forks through the yokes is because its the easyest and cheapest...buying some shims and having them fitted is still alot cheaper than replacing the linkage arm to an adjustable one...

OK we'll agree to disagree. But I thought the RC211V is the only bike with digressive rear linkage systems.

cowpoos
22nd December 2005, 20:52
OK we'll agree to disagree. But I thought the RC211V is the only bike with digressive rear linkage systems.

looks like we will....my old [98] TL's ran a digresive linkage...infact very similar to a F1 system....separate damping and spring...most new bikes have digresive systems by using linkages...they would work better if the spring was seperated...but rooms at a premium...

Lou Girardin
23rd December 2005, 09:14
By digressive, do you mean a linkage that reduces the spring rate throughout it's travel? As distinct from nearly every other linkage system that is progressive or linear. That is, the rate increases or remains the same.

cowpoos
23rd December 2005, 09:49
By digressive, do you mean a linkage that reduces the spring rate throughout it's travel? As distinct from nearly every other linkage system that is progressive or linear. That is, the rate increases or remains the same.

yes...road bikes should be linear or digresive....digresive being what is really desired....have a look at the angles on the linkages on one of the new sports bikes in your shop....imagine how the leverage creates differing forces through the full range of travel...

I think we need to meet up some time and have this yarn over a beer ot two...its a hard subject to talk about with just words...
Its also one of those subjects that there's lots of wives tails talked about...when the simple matter is...its actually quite basic physics to grasp...but bloody trick in the really world because of many factors...

R1madness
23rd December 2005, 12:36
Why????

Why do you think teams fit telemetry to bikes ??? so they can fiddle with a few adjusters ( that will only change the fork action a few percent ????)

I for one cant afford telemetry, and there NO way I can tell the difference between settings on a poorly set up bike ( for the record when I fitted my front end it had been valved for a proffesional, who weighed 70 to 80 kg...sags ok but rebound shim stack ...way off... would kick up on the jump face ) So NO amount of clicker settings would cure it ,,I could notice the difference between 8 or more clicks either way ...just ,,the rest of the time I was hanging on for dear life with the front popping out of the ruts on corners , which tended to high side ,,,,

So I had a email session with Jeremy wilkey , MX Tech ,,,and thats what was suggested to me ..and it worked you can see what is happening to the forks , how the bike wasnt getting traction ....

Still whole lot easier to twist a few clickers and change the oil ... :corn:

Stephen

Its just the way i see things. The bikes these days are fantastic, even the standard suspension is great. After all Stroudy took out the 600 class last year on a bike that ran the std rear shock for the first 3 rounds. Yep sure a revalve and spring rate match in the front would make for a noticable improvement but most people will not do it because of the cost. Yes i agree it is cheap speed but most people just dont care. They would rather buy a pipe. That way you can see the $$$ spent.
Telemetry, its great. Pity its banned here in NZ racing.
For what its worth all the $ in the world will not help if you are on crap/cold tyres.
If you understand suspension and how it works and what makes it do what, you can get a lot out of it.
I dont disagree with ya Brian just think most people want the best out of the std suspension without spending the cash. mugs.

TwoSeven
23rd December 2005, 13:39
looks like we will....my old [98] TL's ran a digresive linkage...infact very similar to a F1 system....separate damping and spring...most new bikes have digresive systems by using linkages...they would work better if the spring was seperated...but rooms at a premium...

I'm having a bit of trouble understanding the terminology you guys are using.

As far as I know there is no such thing as a digressive linkage. I think what is meant is a digressive shock (or digressive damping) which uses a progressive shim stack to provide a high initial stiffness [the opposite is called a 'rising rate' shock which starts with a low initial stiffness]. The linkage is simply the bar that joins the bottom of the shock to the chassis the swingarm and chassis. The bit that connects to the chassis is called the link rod. Its purpose it to translate the virtical distance of wheel travel to a force applied to the end of the shock - usually using a reduction ratio.

A [pro-link] linkage uses tangenital forces (from what I can see) and is normally progressive or linear (very rare these days) - Since the other word for tangential is digressive perhaps the latter word was substituted by mistake.

The only other thing I can think of is that the linkage rod has been very badley designed and has an angle making a high resistance before it pivots enough to travel freely - I cant see that happening on the Honda unit pro-link. The high initial resistance would make it 'digressive' in behaviour [to use the damping term].

The RC211V uses a bog standard unit pro-link system, similar to the ones that are fitted to the cibby 600 and 1k (but obviously a higher spec). It's upper mount is on the swingarm rather than on the frame as on the old pro-link system. If they [honda] have reshimmed it to be digressive, no-one would know except the chap that builds the shock. But the design change is simply to make the shock go straight up and down, rather than also back and forth as well and to remove forces being applied to the chassis.

Brian d marge
23rd December 2005, 14:05
Its just the way i see things.
I dont disagree with ya Brian just think most people want the best out of the std suspension without spending the cash. mugs.

Thats cool, The standard suspension is a lot better than a few years ago, but the factory is a bit myopic they ( honda ) really dont know whats going on in the outside world ,,,( american honda I rekon is saving their arse!) look at this years tokyo motor show ,,,Retro ,,brand new copys of 20 year old shit !

Anyway I digress ,,,If you are 70 kg or there abouts the standard suspension is fine ..you probably wont even notice anything at road speeds ,,

When I started Mx I just got on the bike and opened the throttle ...after going over the handlebars a few times ,,,and taking the knobs of the top of the front tyre ...I sat down ( nearly a year ago now ) and had a good long think /play.
What I wanted was to use the stock suspension to get the best bang for bucks ,,( ie not spend anything ) ,,,but I eventually admitted defeat and bought the correct spring rate for the bike ,,,,this then required a change in the shim stacks ,,, oh well its all education ,,,

at the mo ,,,The bike is in a million bits , I am going stiffer again in the front so I can leave the compression shim stack relatively soft , so that the spring will take the hits through the whoops ...( I get nailed through those things ,,,)

Stephen

Lou Girardin
23rd December 2005, 14:17
The RC211V uses a bog standard unit pro-link system, similar to the ones that are fitted to the cibby 600 and 1k (but obviously a higher spec). It's upper mount is on the swingarm rather than on the frame as on the old pro-link system. If they [honda] have reshimmed it to be digressive, no-one would know except the chap that builds the shock. But the design change is simply to make the shock go straight up and down, rather than also back and forth as well and to remove forces being applied to the chassis.

You may well be right. I was thinking back to an article I read that said the Honda has a digressive linkage. It does seem strange that they want a falling spring rate as the spring compresses though. I understand the advantage of digressive damping. All going well I'll have set of Traxxion valves on the Bandito soon.

TwoSeven
23rd December 2005, 21:06
Maybe, it is digressive in the damping. I've always wanted to get hold of data logger readouts off of race bikes to see whats going on. It could be that under hard braking or acceleration there is a requirement to have a high initial resistance, then have it slide into a different setting after.

What to dirt bikes normally have on them, they would be an ideal candidate wouldnt they ?

cowpoos
23rd December 2005, 21:23
Maybe, it is digressive in the damping. I've always wanted to get hold of data logger readouts off of race bikes to see whats going on. It could be that under hard braking or acceleration there is a requirement to have a high initial resistance, then have it slide into a different setting after.

What to dirt bikes normally have on them, they would be an ideal candidate wouldnt they ?

nope dirt bike's use a progresive set up...which is as easy as pie for a tuner to set up...

cowpoos
23rd December 2005, 21:35
I'm having a bit of trouble understanding the terminology you guys are using.

As far as I know there is no such thing as a digressive linkage. I think what is meant is a digressive shock (or digressive damping) which uses a progressive shim stack to provide a high initial stiffness [the opposite is called a 'rising rate' shock which starts with a low initial stiffness]. The linkage is simply the bar that joins the bottom of the shock to the chassis the swingarm and chassis. The bit that connects to the chassis is called the link rod. Its purpose it to translate the virtical distance of wheel travel to a force applied to the end of the shock - usually using a reduction ratio.

A [pro-link] linkage uses tangenital forces (from what I can see) and is normally progressive or linear (very rare these days) - Since the other word for tangential is digressive perhaps the latter word was substituted by mistake.

The only other thing I can think of is that the linkage rod has been very badley designed and has an angle making a high resistance before it pivots enough to travel freely - I cant see that happening on the Honda unit pro-link. The high initial resistance would make it 'digressive' in behaviour [to use the damping term].

The RC211V uses a bog standard unit pro-link system, similar to the ones that are fitted to the cibby 600 and 1k (but obviously a higher spec). It's upper mount is on the swingarm rather than on the frame as on the old pro-link system. If they [honda] have reshimmed it to be digressive, no-one would know except the chap that builds the shock. But the design change is simply to make the shock go straight up and down, rather than also back and forth as well and to remove forces being applied to the chassis.

first digessive means basically starts off firm and gets softer as it progresses...for a road bike that at high speeds hit a small [or large] bump...you need to move the suspension quickly...but more importantly...when on large lean angles [or even medium ones] the suspension is compramised...as the suspension is trying to transfer a vertical force into a semi horizontal force...and there xtra fricton involved...there is more resistance invloved...making motorbike suspension work propally at high lean anglers[and medium one] invloves making the suspension digresive in nature...since you bike is cornering the suspension is loaded somewhat....probally around 40-65% of its travel is loaded on to it....so the softer nature of the suspension at those lean angles can be transfered alot easyier thru the suspension rather than making the bike wooble or tyres lose traction...its hard to see how this works in words...but I know you will think this through [judging by your posts you a real thinker]

think about what will happen to your bike at 45 degrees...if it hits a bump that will impact your bike in a vertical nature...where will the force's travel if the suspension is linear or progresive [progesive meaning harder as the suspesion moves through its travel]

TwoSeven
23rd December 2005, 22:24
Are you talking front or rear suspension. Lean angle has not much affect on front other than stiction, and sidewall push for the tires.

But, what you are saying is that the bike weighs more as it goes round a corner so therefore needs more resistance. However, a progressive fork would also work - but, if there is a bump in the corner, there wouldnt be sufficient travel left to deal with it. So digressive would still allow for fork travel.

cowpoos
23rd December 2005, 22:30
Are you talking front or rear suspension. Lean angle has not much affect on front other than stiction, and sidewall push for the tires.

But, what you are saying is that the bike weighs more as it goes round a corner so therefore needs more resistance. However, a progressive fork would also work - but, if there is a bump in the corner, there wouldnt be sufficient travel left to deal with it. So digressive would still allow for fork travel.

are you serious!!!!! your just trying to wind me up or something....?????

TwoSeven
24th December 2005, 01:16
no, I drew [or tried to] a vector diagram on what you are talking about. Somehow, you are implying that the bike increases its weight when it goes around a corner.



since you bike is cornering the suspension is loaded somewhat


Only way you can compress suspension is to increase the mass of the object on top, or put a bump underneath - you mentioned no bump. So must be increasing the weight of the bike.

Sideways friction applied to a shock added to its initial resistance is called stiction. Shorted form of static friction caused by two surfaces rubbing together. Modern prolink shocks move up and down and have no (or almost no) sideways movement, so I figure you must be talking about the front shock. I figure you are talking about stiction because:



as the suspension is trying to transfer a vertical force into a semi horizontal force...and there xtra fricton involved

Otherwise it seems you are talking about increased spring preload requirements and lack of preload on a weak spring is one reason why you seem to think you get 60% fork travel when cornering. Personally I would like to see a data trace on this behaviour occuring.

You still havnt mentioned if you are talking about front or rear :)

Its the use of the word digressive thats confusing me.

I've always heard it as low speed damping. That is high damping force at low speed, normal damping force at high speed. Not sure where all this sideways stuff comes into it.

Brian d marge
24th December 2005, 03:07
I ll quickly jump in here before I toddle off to bed,

All forces can be broken into 2 , a X and a Y force a vector and can be moved anywhere as long as you dont change the magnitue and direction of said vector
So A bike leaned over at 45 deg will have a force of a downward force and a horisontal X force in the direction of the outside of the Curve ( stiction is the force due to friction of the seal against the metally bit ...friction is a ratio between acting force and reacting force acting at 90 deg to the surfaces )

So if the horisontal component of the force is increased either through a greater lean angle or whatever , stiction will increase as the acting force on the metally bit of the fork has now been increased .

So Force is mass times acceleration ,,so if you soften the damping...... the SPEED of the shaft is greater , and will over come the stiction allowing more precise control ( as in the spring will absorb the energy and the oil will take less energy ...FOR HIGH shafts speeds only ,,as soon as the shaft speed comes back down ,,,the oil will take more of its share of the transfer of energy ,( the action of shoving oil through larger or smaller holes )

MX damping is a mixture , My front forks are digressive ,,I left the high speed shim stack intact and increased the low speed . by 2 x o.1mmx 16mm shims
A digressive linkage system I need to see a photo off..as I cant picture one now ...to late,,,to tired and half pissed ,,sorry folks long day !!!:pinch:


Sorry I just bashed this reply out before crashing ,,,so any ( or if total crap ) technical foparas ( spanish for crap) ,,,see my Lawyers
Huey doo-em and How

Stephen

abd if it made any sence at all ,,you are drinking better shit than me !!!

R1madness
24th December 2005, 10:21
Thats cool, The standard suspension is a lot better than a few years ago, but the factory is a bit myopic they ( honda ) really dont know whats going on in the outside world ,,,( american honda I rekon is saving their arse!) look at this years tokyo motor show ,,,Retro ,,brand new copys of 20 year old shit !
Stephen

Hi Stephen. Yea man the factory skimps on the suspension to save a few $$$$$. Then the fast guys spend the extra cash on WP or Ohlins and the rest suffer by comparisum. I think all racing should be made cheaper by the introduction of a PURE PRODUCTION CLASS. Imagine what it would be like if you had to run std shocks and std valveing. Yes everyone would be slower thats true but maybe it would force the factorys to make their shocks and forks as good as possable.
Yea i know its a pipe dream but look at the one class racing from around the world where everyone is on similar machines and $$$$ dont count. AWSOME and CLOSE racing.

Retro is cool when ya get to my age (not :angry2: ) and we are tha ones with the $$$$ (well not me personally) the factorys think. And since we (the old ones) are all suposed to be returning riders ( :Oi: not me i have never been without a bike) we dont need fun or modern bikes :puke: The bikes they are showing are the same as the shitters i started riding on 20years ago. maybe i should not have sold my old shitters. They would be all the rage now hahahahahaha.

R1madness
24th December 2005, 10:22
Thats cool, The standard suspension is a lot better than a few years ago, but the factory is a bit myopic they ( honda ) really dont know whats going on in the outside world ,,,( american honda I rekon is saving their arse!) look at this years tokyo motor show ,,,Retro ,,brand new copys of 20 year old shit !
Stephen

Hi Stephen. Yea man the factory skimps on the suspension to save a few $$$$$. Then the fast guys spend the extra cash on WP or Ohlins and the rest suffer by comparisum. I think all racing should be made cheaper by the introduction of a PURE PRODUCTION CLASS. Imagine what it would be like if you had to run std shocks and std valveing. Yes everyone would be slower thats true but maybe it would force the factorys to make their shocks and forks as good as possable.
Yea i know its a pipe dream but look at the one class racing from around the world where everyone is on similar machines and $$$$ dont count. AWSOME and CLOSE racing.

Retro is cool when ya get to my age (not :angry2: ) and we are tha ones with the $$$$ (well not me personally) the factorys think. And since we (the old ones) are all suposed to be returning riders ( :Oi: not me i have never been without a bike) we dont need fun or modern bikes :puke: The bikes they are showing are the same as the shitters i started riding on 20years ago. maybe i should not have sold my old shitters. They would be all the rage now hahahahahaha.
Have a great xmas all.

cowpoos
24th December 2005, 10:26
no, I drew [or tried to] a vector diagram on what you are talking about. Somehow, you are implying that the bike increases its weight when it goes around a corner.

correct...it does increase its weight...how much...depends on how much speed is involved in the motion and the bike [G forces] speed


Only way you can compress suspension is to increase the mass of the object on top, or put a bump underneath - you mentioned no bump. So must be increasing the weight of the bike.

there are more forces at play than vertical ones...its hard to factor momentuim into drawings


Sideways friction applied to a shock added to its initial resistance is called stiction. Shorted form of static friction caused by two surfaces rubbing together. Modern prolink shocks move up and down and have no (or almost no) sideways movement, so I figure you must be talking about the front shock. I figure you are talking about stiction because:

Otherwise it seems you are talking about increased spring preload requirements and lack of preload on a weak spring is one reason why you seem to think you get 60% fork travel when cornering. Personally I would like to see a data trace on this behaviour occuring.

read Brian d'marge post below yours


You still havnt mentioned if you are talking about front or rear :)

this is irrelivent...as the forces are applied to both ends evenly...if they don't you going to be changing bike geomertry through the corner...so if one end is move alot more than the other you bike will be unstable


Its the use of the word digressive thats confusing me.

I've always heard it as low speed damping. That is high damping force at low speed, normal damping force at high speed. Not sure where all this sideways stuff comes into it.

think about it some more...

TwoSeven
24th December 2005, 13:35
this is irrelivent...as the forces are applied to both ends evenly...if they don't you going to be changing bike geomertry through the corner...so if one end is move alot more than the other you bike will be unstable


This cant be true. A rear shock does not have half the forces applied to it as a front unit would. Simply put, its got a bloomin great chunk of manganese/alloy reinforcing it. Also a rear shock isnt subjected to as much twisting force as the front is when the bike is turning, nor will it be subjected to forwards/backwards bending either. Even the weight applied to it will be different simply because of the bias tha chassis has.

yes, bike geometry does change quite a bit thu the corners.