when i get on the bike and get into my riding position it just doesnt move any. Is something to stiff? I dont know if the spacers or doing that. it seemed kinda strange to me. i took it for a ride doesnt feel strange at all. i havent gotten around to doing the back yet casue i wanted to handle the front but still. im not sure whats going on. if it means anyting my fork bolts(17mm ones ) are screwed out to 7 blocks?
JINKSTER ATTACKS "SUSPENSION"
- Thread starter JINKSTER
- Start date
Well..even taking into account that I'm 240 and you're only 160?..my body weight is causing an extra 15mm more compression when laden...and your's is only compressing 3mm when you get on?..dosen't make sense..even with the body weight delta between us you should still be getting at least an extra 10mm compression but you're only claiming/measuring 3mm.
Initially I thought..hey..meybe his comp damping screw is locked all the way in...but...that dosen't wash either cause if it were it would affect static as well and...it apparently isn't...you're getting plenty of static sag....almost exactly the same amount as my busa's static sag...but then laden my bodyweight compresses 15mm more and you only measure 3mm?
Somethings either not right and/or not getting measured right.
i can explain what i did and you let me know where i screwed up.
1 jacked teh bike up measured from boot to cast iron part 126mm
2 let the bike down measured from boot to cas iron 103mm
3 put twist tie on got on measured from top of tie to cast iron100mm
4 adjust 17mm bolts until my laden sag was just at 89 which is 3.449
Do i need to press or lean on the bars. i havent done my rear either could that have some effect on how low the bike drops when i get on it?
1 jacked teh bike up measured from boot to cast iron part 126mm
2 let the bike down measured from boot to cas iron 103mm
3 put twist tie on got on measured from top of tie to cast iron100mm
4 adjust 17mm bolts until my laden sag was just at 89 which is 3.449
Do i need to press or lean on the bars. i havent done my rear either could that have some effect on how low the bike drops when i get on it?
him: Just cause I can't explain why you're only getting 3mm more sag when laden as opposed to static dosen't mean "you screwed up"...matter of fact?..it sounds like your did everything just as described...I'm just baffled and left at a loss as to why your added body weight is only showing 3mm's more compression...as in...strange.
What are your rebound and compression settings adjusted at?
And just so ya know...the reason 3mms sounds weird to me is this...
Your Busa weighs maybe about 500lbs "wet"....figure about 300 of that is biased up front...and just the weight of the bike compresses it 29mms..then add your weight on top and it only compresses another 3mm's?
sumpt'ins funky...or..for some reason your suspension is "STACKING" like a biotch in that last 3mm's.
Gimme your damping #'s..comp & rebound...in "clicks out".
L8R, Bill.
on the damping im 8 clicks on each from the stock setup to softer. i tried making it softer to make the bike compress more. i didnt really fool with taht too much though just the 8 clicks. it seemed like when i was clicking them nothing was happening as far as compression wasnt chainging so i stopped before i screwed something up.
Okay..well that explains a bit except for the "from the stock setup" part...do you mean to say you "added 8 clicks out" to the stock settings?
Also..what year is your busa?
and...
How many miles on it?
Cause it's all starting to sound to me like your upper range of suspension is completely mushed out...and that's why it's sagging so badly under static and then just a tad when you hop on.
"Time & Use" can cause your fork springs to sag out and get played out all on their own....matter of fact?...right in the shop manual there is a "minimum free length" on the fork springs...and anything under (240mm/9.4") should be replaced...and no doubt things like slamming down wheelies and/or strapping forks down for drag racing will greatly decrease a fork springs life span.
It's the only explaination I can offer at the moment...but one thing is for certain...if your static sag puts 29mm's of compression on your forks but the addition of your body weight only compresses them an additional 3mm's?....somethings definantly wrong with your suspension set-up.
L8R, Bill.
For teh preload its 8 clicks softer than stock. the busa is a 2001 with just over 9k. i got the bike with 2800 on it. From the way the tires, chain and everyting looked i am the only one who beat the shid out of it. So i need to replace the springs in my forks how hard/expensive is that?
So you're saying the laden sag measurement doesn't have to be exactly 3.449. It just has to fall between 3.277 and 3.621.Gentlefolk...please consider this an addendum to the primary post here...
"THINGS YOU SHOULD KNOW ABOUT SPRINGS"
Very short, sweet and concise here...
The industry standard regarding "Tolerances For Spring Compression Rates" is +/- 5%. (but are typically held much closer than that)
What's this mean to you?: Spring to spring, bike too bike suspension settings can and will vary even amoungst riders of equal weight..to a degree..and THIS is why it is so important to set-up YOUR bikes suspension sag numbers TOO YOU and then fine tune to taste and/or personal preference. In this I myself strive to attain a good balance between "Bump Compliance" and "Suspension Performance" (whereby I'm attempting to minimize front end dive and rear end squat....what I call...."The Hobby Horse Affect")
which in turns greatly minimizes front too rear weight transfer during hard braking/acceleration manuvers making the bikes chassis far more stabil during aggressive riding.
To give you an idea?...the magic "laden sag" numbers I came up with by calculating 33% of the forks 4.7 inches of overall travel is 3.449.
Now...if you calculate in the industry standard tolerancing of +/- 5%?...theoretically...with different bikes at the same settings...
5% of 3.499 ='s .172 inches
so at max outboard tolerances our actual laden sag dimensions (even at the same settings) could vary as much as..
.172 (-5%) + .172 (+ 5%) ='s .344 inches max tolerance span on just the spring too spring tolerances alone.
So...this explains why optimum laden sag settings may vary from bike too bike even with riders of equal weight and...there's also naturally induced "Spring Sag" that takes place over time and use.
I figured I'd address that BEFORE anyone inquired.
L8R, Bill.
Is this a correct interpetation??
Hey JINKSTER, great info. Question though;
You've explained how to setup/adjust preload based on rider body weight(basically). However, you recommended some settings for compression and rebound but they appear to be settings for someone close to your weight. I understand that suspension is all about rider preference. But is there a way to adjust compression and rebound by the book similar to the way you described how to adjust preload.
Thanks,
Charles
You've explained how to setup/adjust preload based on rider body weight(basically). However, you recommended some settings for compression and rebound but they appear to be settings for someone close to your weight. I understand that suspension is all about rider preference. But is there a way to adjust compression and rebound by the book similar to the way you described how to adjust preload.
Thanks,
Charles
NO...It's not...not at all....I'm saying just what I said...springs (even at brand new manufactured) can have a delta/tolerance of +/- 5% compression rate wise...my span of 3.277-3.621 was just to show what sort of differential could be encountered just in the manufacturing varience of the springs themselves...to expalin why the same settings may not be optimum "busa-too-busa" and to stress why it is so important that...So you're saying the laden sag measurement doesn't have to be exactly 3.449. It just has to fall between 3.277 and 3.621.Gentlefolk...please consider this an addendum to the primary post here...
"THINGS YOU SHOULD KNOW ABOUT SPRINGS"
Very short, sweet and concise here...
The industry standard regarding "Tolerances For Spring Compression Rates" is +/- 5%. (but are typically held much closer than that)
What's this mean to you?: Spring to spring, bike too bike suspension settings can and will vary even amoungst riders of equal weight..to a degree..and THIS is why it is so important to set-up YOUR bikes suspension sag numbers TOO YOU and then fine tune to taste and/or personal preference. In this I myself strive to attain a good balance between "Bump Compliance" and "Suspension Performance" (whereby I'm attempting to minimize front end dive and rear end squat....what I call...."The Hobby Horse Affect")
which in turns greatly minimizes front too rear weight transfer during hard braking/acceleration manuvers making the bikes chassis far more stabil during aggressive riding.
To give you an idea?...the magic "laden sag" numbers I came up with by calculating 33% of the forks 4.7 inches of overall travel is 3.449.
Now...if you calculate in the industry standard tolerancing of +/- 5%?...theoretically...with different bikes at the same settings...
5% of 3.499 ='s .172 inches
so at max outboard tolerances our actual laden sag dimensions (even at the same settings) could vary as much as..
.172 (-5%) + .172 (+ 5%) ='s .344 inches max tolerance span on just the spring too spring tolerances alone.
So...this explains why optimum laden sag settings may vary from bike too bike even with riders of equal weight and...there's also naturally induced "Spring Sag" that takes place over time and use.
I figured I'd address that BEFORE anyone inquired.
L8R, Bill.
Is this a correct interpetation??
You measure off, then set and adjust "YOUR BUSA's" static/sag #'s too "YOU"!
to attain the 3.449 dimension...33% of your busa's 4.7" fork travel....despite what "The Settings" of others may be.
Since there seems to be some confusion here I guess I should simplify things with the following...
30mm's Laden Sag is desirable for track day/racers and 40mm Laden Sag is THE MAXIMUM I would suggest for those desiring a plusher streetbike/sport touring ride...and personally speaking?...because the Busa's front forks are neutered to a scant 4.7 inches of "Overall Travel" (where most other sportbikes have about 5.5"s of overall travel) I'd advise erring more towards the 30mm end of things...but with me at 240LBS?...I can't get any better than 45mm Laden Sag with the stock springs as they are far too soft...making my busa too softly sprung up front to facilitate optimum suspension/handling.
L8R, Bill.
<!--EDIT|JINKSTER
Reason for Edit: None given...|1116249499 -->
Unfortunately?...Not that I'm aware of Charles...but what I can share is what I look for which is...
Front Forks:
Compression Damping: I try to set compression damping as tightly as I can to....
a. reduce as much "Front End Dive" under hard braking as possible yet...
b. Not get it so tight that I'm spiking my own wrists when encountering road imperfections/bumps.
In other words...I want it tight enough that my front end feels planted and renders great feedback yet compliant enough to soak up the sharp edged stuff.
Rebound Damping: Just the opposite of comp. damping above?...Here I'm watching to make certain that my front forks aren't RISING excessively quick under hard acceleration..if they do?..I add rebound damping by turning clicks inward (Clockwise: which closes up the bypass ports forcing more damping affect) also...
I check for to much rebound damping by simply standing alongside of the bike and PULLING UP on the bars...and if I can get it to come up a 1/4-1/2 inch or so and it stays there?..chances are the bike is suffering too much rebound damping..and the rebound damping isn't allowing the suspension to fully return to full static suspension...and I'll reduce rebound by clicking the rebound screw out (Counter-Clockwise: which opens up the bypass ports reducing the damping affect)
Same with the rear shock...dose that help?
L8R, Bill.
Charles...here's two excellent articles that word things probably much clearer than I can...
http://www.motorcyclistonline.com/howto/suspensionadjust/
and...
http://www.sportrider.com/tech/146_9604_tech/
Some light reading never hurt anybody!
L8R, Bill.
http://www.motorcyclistonline.com/howto/suspensionadjust/
and...
http://www.sportrider.com/tech/146_9604_tech/
Some light reading never hurt anybody!
L8R, Bill.
Bill,
After reading your post I felt compelled to call Traxxion Dynamics, especially since I will be going to the Gap this month and dont want any suspension surprises while i'm there. I'm 280lbs and Lee is setting me up with a 1.15 front and I have sent them my rear shock as well. Figured I might as well get everything set up as well as I can without buying ohlins or penske stuff. Lee said though that they might have to revalve my rear shock because of the newer stiffer spring and the stock valving might not be able to control the rebound. They are going to put on the new spring and see how it works out, apparently they have a shock dyno to check it on. But, if it isnt going to be right he said to go through the rear shock it will be around $300 to get it right. While still half the price of the cheapest penske I wonder if it wouldnt be worth springing for the penske anyways. Anyways, are you considering doing your rear shock or have you known anyone who has and how has it worked out? I would hate to spend the $ modifing the stock shock then wish I bought the penske. Is there any other advice you could give someone going to the gap for the first time? Other good rides to go on in the area?
Jeremy.
After reading your post I felt compelled to call Traxxion Dynamics, especially since I will be going to the Gap this month and dont want any suspension surprises while i'm there. I'm 280lbs and Lee is setting me up with a 1.15 front and I have sent them my rear shock as well. Figured I might as well get everything set up as well as I can without buying ohlins or penske stuff. Lee said though that they might have to revalve my rear shock because of the newer stiffer spring and the stock valving might not be able to control the rebound. They are going to put on the new spring and see how it works out, apparently they have a shock dyno to check it on. But, if it isnt going to be right he said to go through the rear shock it will be around $300 to get it right. While still half the price of the cheapest penske I wonder if it wouldnt be worth springing for the penske anyways. Anyways, are you considering doing your rear shock or have you known anyone who has and how has it worked out? I would hate to spend the $ modifing the stock shock then wish I bought the penske. Is there any other advice you could give someone going to the gap for the first time? Other good rides to go on in the area?
Jeremy.
No...I'm not considering doing anything with my rear shock...that part i lucked out on and at 240 LBS with the spring at max preload it seems to take sag settings just fine..for me..for now.
Penske shocks are 1st class but carry a huge price tag...if money wasn't an issue in my life and I planned on keeping the bike a good long while yet?...I'd maybe splurge on the penske.
That said?...If money was an issue in my life and I needed to be wise of wallet?..there's not a damn thing wrong with a properly rebuilt/revalved stock/oem shock..especially one that's been on a shock dyno to be custom sprung and valved for you and your bike..the only thing missing as opposed to the penske will be the remote gas damping adjust/cylinder.
Note: Ya might wanna ask Max, Martin or Lee at traxxion about the possibility of "ELKA" having a replcement model shock for the busa...theuy would be priced somewhere's between a oem rebuild and the penske..with a remote gas/damping adjust...yet another option worth consideration.
Outside of that? I believe you're gonna be pleasantly surprised how well your Busa handles after it's properly sprung and suspended..custom tuned to your weight range.
As far as advice on the gap goes?...be very careful on the dragon...it's extremely tight and technical and more suited to a 250 Ninja than a busa...Cherohola is funner but watch for popo and the decreasing radius turn at mile marker 11..."The Foothills Parkway" rox and is ideal for the Busa...143 into 28 out of Robbinsville leading into Fontana and the CROT (cross roads of time) is an excellent run as well.
L8R, Bill.
Imho?....on a 4 year old bike that you drag race avidly?...
He11 Yes. LOL!!!
Expense: I paid $161 to traxxion for their 1.1 Omni Spring Kit which included...
$105 for the set of 1.1 straight rate springs
$14.95 for the Omni Buffer/Spacer Kit
$29.95 for a Fork Spring Compressor Tool (needed to do the job)
Plus shipping came to $161.
Level Of Difficulty: I'll be changing mine out in the next day or two and doing a step-by-step to post here...front end of the bike needs to be proped up to get the forks off...and I don't have a steering stem style front stand so...that'll be the toughest part to figure out but outside of that should be a piece of cake.
L8R, Bill
If your looking for "Cheap" you might try racetech as they don't offer anything like the omni buffer kit (which is only $14.95 and imho money well spent) but even racetech springs and spacers are gonna cost very close too the same and no matter who's springs you go with you're gonna need the spring compressor tool...(which is of great use on any USD fork)..or?..you can toss it in the classifieds after you're done using it to recoup some cash I guess...but...I'm keeping mine.
BTW....fork oil dosen't last forever either...according to the pro's it should be changed out every 10K miles or 2 years..and I've changed enough old fork oil to believe that.
Also... far better damping quality/compliance can be achieved (with the stock valving) by switching up too a lighter weight fork oil...I'm going with "Spectro 5W" as me and my associates believe the LO1 suzuki callout to be 10W stock fork oil...5W will flow quicker through the stock valving....yeilding "quicker hydraulic crosstalk" between damping and helping to reduce "hydraulic lock" on compression damping over sharp edged road imperfections.
I'll take a bunch of pix as I go which should help ya'll to gain a far better understanding of "The Whats & Why's"....and then I'll even show, describe and explain the difs and advantages between "Progressive VS Straight Rate" fork springs.
L8R, Bill.
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