redelk
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posted March 30, 2003 10:26 PM
 Edited By: redelk on 23 Apr 2003 18:57
Learning curve with a 7R swingarm - suspension questions and help needed
Needless to say, with the limited sources of information and not all of it being quite "on target", this project has been both frustrating and pleasurable. Considering what the ratio has been so far, I would have been better off trying to "score" with my ex-wife.  A full report detailing what all was involved. parts needed or modified and the various "do's and DOH's"... all with accompanying pics, will be coming soon.  Speaking of a "tease", here's a pic of the new arm on the bike.
First, I am desperately needing opinions or "solid" information on a major problem that I need to solve.
After getting everything on and being "oh so careful" not to overlook a single thing, this evening was going to be the bike's maiden voyage with the new arm. A basic shake down to see what I might have overlooked or was different then expected. After I warmed the bike up, I took off the stands, put my helmet on and got onto the bike. After close to three years of having to "tip toe" the bike (30" inseam), I was startled when my right foot became firmly planted on the ground. :o So startled as a mater of fact, I damn near dropped the bike!  I'M SERIOUS! "Startled" isn't the right word... FUCKIN' FREAKED OUT might better qualify.  My bike was suddenly slammed like a drag bike! 
After checking to make sure that the suspension had not collapsed or there was a "minor" part forgotten or left loose, I could find nothing wrong. Then I realized what the likely culprit was. Part #39111-1163... suspension tie rods (aka links or "dogbones"). I had reinstalled the 12R's suspension arm and links onto the 7R's swingarm. Obviously, not the right move unless I want to improve my 60' times (which are beyond "help"). So, that brings me to my questions about links and suspension arms (the little elbow thing that connects to the shock, links and frame).
SUSPENSION LINKS AND ARMS 101
It now seems obvious that I probably should be using the links for a 7R on a 7R arm. That is, providing that the 7R links are shorter. I'm guessing that shorter links will raise the rear ride height. The question is, what is the ratio between link length and change in ride height?
Here's a pic that might show a possible source for part of the problem.
You'll notice that the horizontal distance from the center of the swingarm pivot to the center of where the links connect are basically the same. What's different is the vertical distance between the two. The 7R is well over .1" and could be closer to .25" further down then the 12R's arm.
It appears that from looking at Muzzy's lowering links, a minor change in the link's length will have a dramatic change on the ride height. They say their lowering links can lower the ride height by 1.25" or 2.5", yet the centers of the holes on the links look to be less the 1" apart. Would it be fair to say that it's something like a 2 to 1 ratio? Something like 1.25" on the link = 2.5" in the ride height?
Would getting the 7R links be enough? Since the linkage arm is different as well, wouldn't that have an effect as well? Also, since the point where the linkage arm attaches to the frame could very well be different, would using the 7R linkage arm even produce the desired results or just make matter worse by jacking the rear up too much?
Being a "voodoo science" and best and more like a trip into the unknown, this project has produced more questions and even fewer answers (at least from those that have done this before). I remember Swft posting on a ride height thread back in October where he said, "Shorter dogbones changes the ratio, which effectively changes the spring rate. Shorter lever arm means that the spring rate would be higher, methinks.". This sounds like pretty valid theory to me, but what happens when the location of where those links connect to the swingarm change as well (as in the case of the 7R vs. the 12R). It just makes the question of using just the 7R links or both the links and the linkage arm all the more confusing.
Not having either unlimited finances or time, I really need some input on this. I'd prefer to not have to buy the linkage and all the bearings (4), seals (6), zerk fittings (3), sleeves (3) and bolts (3 or 4), associated with getting a 7R linkage arm. I'll have more financially tied up in just those parts that the total amount I have spent thus far. I would hope that just by using the 7R links by themselves, would adequately address the problem. Also, since we had to cannibalize the 12R swingarm for a needle bearing, I can't ride until either I resolve this problem or get new bearings in the 12R arm, as well as a new chain, new rear caliper bracket, new axle collar, etc.(details will be in the upcoming report). I would like to at least ride sometime this MONTH.
I got till Tuesday to try and figure it out. That's when I'll be calling my dealer and ordering the parts. Depending on where they are coming from, some might need to be shipped "priority" if I am to have any hopes of riding next weekend (then it'll probably end up raining all weekend). Eventually, I would like to be like GOZR and have all the parts that would allow me to swap the two arms when ever I wish, but because of the current limited funds aspect, I'm kinda stuck with the 7R arm being on the bike and I'm hoping to not spend any more than necessary to get it up and running.
Even though GOZR hasn't replied any of my requests for information yet, I would still like to thank him for the tip on the axle collar (even though he deleted the post shortly there after). All the same, I would question some of the pics and measurements he has on his forum about the swap. Then again, I might have just as easily misunderstood what he was explaining (a definite possibility on my part - no blaming others here).
Also, we all know that Bart would not know a dogbone from a dog dick (maybe he would) and even if the guys that did his work drew pictures for him, I doubt if the "information" would survive a "Bart translation" intact or be of any practical use. Don't try to deny it either, Bart 
So it boils down to hoping for some thoughts, opinions and speculations from the rest of you knowledgeable guys on which direction I go from here. Swft? Z? Ted? Y2K? Anyone?
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There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.
-Ernest Hemingway
   
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harryzx-12
Needs a job
Posts: 3643
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posted March 31, 2003 03:35 AM
You might want to consult Bart Rossi as he knows everything,don't believe me, just ask him!
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"Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body, but rather to skid in sideways- Body thoroughly used up, totally worn out...Screaming "WOO HOO, What a Ride !!!"
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swft
Needs a life
Full throttle!
Posts: One MEEEEEELLION
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posted March 31, 2003 06:38 AM
Edited By: swft on 31 Mar 2003 06:40
Sherm,
I think you would be better off getting some fully adjustable links, like the Kennedy links. That way you can get the ride height right where you want it.
Here's the info I have:
765 724 2225 ext 14 for sales, lowering links, ask for Victor
kirkham.sonny@kennedymachine.com
And you should be able to explain your need to him and get one custom made.
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jonwright
Needs a job
Posts: 2416
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posted March 31, 2003 07:25 AM
Edited By: jonwright on 31 Mar 2003 07:25
Funny: a long post starts with "needless to say..."
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kawachan
Pro
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posted March 31, 2003 08:45 AM
I'd go with SWFT!
Either that, or figure out what you need and get a local machine shop to cut you out a set to your measurements.
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RED NINJAS RULE!!
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ballisticzx12r
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posted March 31, 2003 09:55 AM
Sherm,
All I know is that you must custom machine the brake caliper unless you order a ZX-7r rear wheel.
Other then that mine is getting the custom map written today, computrack is done, and found out that the 12 spring that comes on the mid penske is too stiff for the shorter swing arm of the 12.
No other help can be given, all I do is ride them...
Just remeber gas is on the right.
Barto
P.S. sherm I don't wan tany fucking excuses come may that you can figure it out and that is why you are still slow.
____________
Be fast and Be safe
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redelk
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posted March 31, 2003 10:20 AM
Edited By: redelk on 23 Apr 2003 18:52
Bart, no excuses on either. I'll figure this out on the swingarm and I've already figured out why I'm so slow... I'm a untalented wuss. Plain and simple. I can't change the later, but I will fix the swingarm.
Here's a couple of current pics. It looks like the bike has been lowered approx. 1.5" or so. I,m only guessing by using previous pics of the bike and comparing the relationship between the tire and other parts of the bike (i.e. where the canister bolts to the bracket).
From the looks of it, it appears that the 12R dogbones are probably a 1/2" or so too long and when combined with the lower mounting point on the 7R swingarm are the main source of my problem.
I hope to call Victor at lunch, since using the 7R dogbones might help, but might not be the "perfect" solution.
____________
There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.
-Ernest Hemingway
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sledesigns
Parking Attendant
Posts: 5
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posted March 31, 2003 11:01 AM
I believe the 00-03 9R arm has all of the same geometric dimensions as the 12 arm but 1" shorter and an extruded instead of cast front bracing, incase you wanted a swingarm shop to shorten it more. Maybe trade with a 9R guy who wants to dragrace with an inch more wheelbase.
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Ninjaman12R
Needs a job
as a Deal's Gap tour guide.
Posts: 4767
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posted March 31, 2003 11:08 AM
For what it's worth.....
For what it's worth, there may be a few bugs for you to iron out Sherm, but the bike looks friggin' SWEET. I'm sure you'll get everything like it needs to be, it just may take a little time and $$$$$$. I understand your concern with the issues, especially after all the work(and $$$$)you've put into this mod.
Once again, the bike looks killer with that 7R swingarm,.....very nice.
____________
What we're dealin' with here is a complete lack of respect for the law.
Sheriff Buford T. Justice of TEXAS
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redelk
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posted March 31, 2003 11:24 AM
Edited By: redelk on 31 Mar 2003 11:25
Rick, the point is that this is another project being performed by one no money, no tools, dumbass Arkie redneck. Here's what I got in it so far...
$66.00 for swingarm off e-Bay
$16.15 for sending payment FedEx
$43.93 for swingarm shipping FedEx
$85.00 for new bearings, etc.
$10.00 for a can of black powder coat
$211.08 total
Technically, it cost me two bearings to get the bearings pressed in (details to come). My "machine shop" tools consisted of a air powered die grinder, a dremil, a belt sander and a plastic micrometer. Not to mention my WMD tools (Weapons of Mass Destruction - hammers, broken screwdrivers, air impact, etc.). The measly expenses I have had so far are almost more then I can handle right now. That's why I'm trying to keep my costs down as much as possible.
____________
There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.
-Ernest Hemingway
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Ninjaman12R
Needs a job
as a Deal's Gap tour guide.
Posts: 4767
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posted March 31, 2003 11:59 AM
Hmmm....
$211.08 !!!! Way cheaper than I figured it would be!!!! That won't keep me in rollin' papers this year.
Seriously, I hope the work involved (and cost) in getting your bike ironed out is minimal. Am I correct in thinking that the adjustable 7R links will address the ride height issue??? Then all your faced with is the spring being too stiff???? How much do you have your preload jacked up????
____________
What we're dealin' with here is a complete lack of respect for the law.
Sheriff Buford T. Justice of TEXAS
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redelk
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posted March 31, 2003 02:04 PM
Right now, I can only hope that the links will return the rate back somewhere close to "normal". It's just that changes as small as a fraction of a degree here or fraction of an inch there causes all previous "rules" and "settings" to be thrown out the window. They no longer apply.
I doubt if the suspension "elbow" has really had an affect on the shock angle or rate since both the shock and "elbow" are 12R parts and the distances/angles from the frame mount to the shock mount have not changed. Since the both swingarms mount to the same point on the frame, that leaves the dogbones and it's relationship to the swingarm as the sole factor.
I'm going to call Victor right now (hoping that he's still there today) and see what he says.
____________
There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.
-Ernest Hemingway
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zx1012r
Expert Class
Posts: 125
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posted March 31, 2003 02:17 PM
I love the swingarm mod but I'm not so sure about the pink flamingo mod! Also don't forget you have some height adjustment at the top of the shock. If the dogbones put you in the park then you can fine tune up there.
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jonwright
Needs a job
Posts: 2416
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posted March 31, 2003 03:40 PM
But, how does it ride???
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redelk
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posted March 31, 2003 10:19 PM
The pink flamingo mod is good for at least 8 mph increase. I promise. Try it and you'll see.
UPDATE and GOOD NEWS!
I took swft's advice and called Victor at Kennedy Machine. What we are going to try is the dogbones for a 6R. If I don't find a setting I like, I just tell him which one is closest and what direction I want to go. With that as a reference point, he will machine out another set to my specs. Then we will swap the 6R set for the custom set.
The best part is that if I do have to send the 6R set back, there will be no additional charge for the making the custom set (if needed)! He hopes to have the 6R set made and shipped by tomorrow and assures me that I will have them in my grubby little hands by this Thursday!
sledesigns, there is no one in this state (remember, I live in Arkansas) that I know of that even remotely has the skill or more importantly, the experience in cutting, welding or doing any other mod on a bike swingarm. Even if there were someone remotely close, I don't know if I would even trust their work on such a project.
It would be one thing if I was just drag racing or some other "limited use", but I plan on putting many more miles (getting close to 40K now) on this bike before I trade it in on a 10R. I just can't feel comfortable riding a bike while knowing some local yahoo had been cutting and welding on it.
zx1012r, Yeah, I know, but I haven decided on which way I tweak it. I have thought about both using shims as well as adjusting the collars on the spring. I want to get as close as possible with the dogbones. Right now, I'm thinking about using the shims as my first option, if some minor adjusting is needed.
I'm guessing that by adjusting the collars on the spring, it will not only change the ride height, but I'm figuring that the change in the shock's preload and could have ill have effects on other aspects of the bike's suspension compression and rebound damping. I'd personally prefer to use that shock to fine tune the damping and get the proper starting point for ride height with the dogbones and shims (if necessary).
It could just as easily be a combination of using both or then again, fine tuning with just the shock could be the route to go. It's too early to tell. I figure that there will be several other aspects I'll have to consider, such as the location of my fork tubes and if I'm going to keep running a 120/65 up front or switch back to a 120/70.
Man, this is just so damn complicated for a simpleton like myself!
BTW - Victor's new e-mail address is victorakasuper@hotmail.com
____________
There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.
-Ernest Hemingway
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Zhooligan
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posted March 31, 2003 10:44 PM
Thanks for all the info and research Sherm. Make sure and be careful coming out of turns while you work on this. With it squatting like it is, it will turn slower etc., but when you get her up in the air she's going to change and a bump coming out of a turn with the throttle screwed on will or could cause a serious tank slapper. I'm sure you have thought of this, but better safe then sorry. And remember as silly as it sounds the harder you hold on and fight a tank slapper the worse it gets.
____________
To those who do not count their life in years, but in how life
has touched them in the past and how much it can hold in the
future; -- Youth is forever.
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redelk
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posted March 31, 2003 11:53 PM
Edited By: redelk on 6 Apr 2003 18:38
I didn't even ride it out of my driveway with it slammed like this! I would not even move the bike around with the engine running. I have no intention of "jackin' up the rear to look like some perceived racer, either. I figure that even the OEM height will be a handful with the shorter wheelbase.
There be some serious math going on here... I think I'm gettin' a brain ache.
____________
There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.
-Ernest Hemingway
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sledesigns
Parking Attendant
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posted April 01, 2003 07:11 AM
Looks like a cool, worthy project. You could easily drill extra holes in the stock 12 links to find the general area of height you want to be in. Maybe drill 3 or 4 extras close together like the Muzzy multi-position links. Just vise grip the two links together when drilling so the holes line up when you're done. You could sit on it, bounce, see how it works, etc. Later, order links with the hole spacing you found works, or get some 6061 aluminum bar and make your own links, cheaper, faster than ordering. Getter done this weekend! I'm planning on a Northern Ark. cruise this weekend to watch my 12's odo flip 20k. Good Luck
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redelk
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posted April 03, 2003 12:40 PM
As Victor promised, the new dogbones arrived here at work. Can't wait to get them home and try them out.
____________
There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.
-Ernest Hemingway
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ballisticzx12r
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posted April 04, 2003 06:37 AM
Its Fucking Great
I had my first track day yesterday with the 7 swingarm. The best way to explain it is like choping 80 lbs off the bike. It turns in faster then I would have ever believed, with out question the best handling mod I've ever done.
Bart
____________
Be fast and Be safe
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jonwright
Needs a job
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posted April 04, 2003 07:36 AM
Does this decrease in wheelbase make the bike more wheelie prone? What about stability at 140+?
j
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redelk
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posted April 04, 2003 07:45 AM
LATEST UPDATE
BAD NEWS-WEIRD NEWS-GOOD NEWS
BAD NEWS
Put the dogbones on. Still not enough difference to correct the ride height problem (pic of the 12R vs. Kennedy 6R dogbones to come). I called a salesman at my dealership and asked him to attempt to measure a 7R dogbone (hole center to hole center) on a bike on the showroom floor (not a real easy task). He said it was an approx. 7.25".
Since this is close to, if not longer then a 12R dogbone, it leads me to believe that a 7R supension arm ("elbow") would be needed as well. As I mentioned earlier, that would be an expense I'd prefer to avoid. At least for now.
WEIRD NEWS
Without having a 7R elbow, the angle of the rear shock is too steep for the opening of the swingarm and actually makes contact with the swingarm on the rear part of the opening. It also appears that this can be corrected by turning the top shock mount around. This is not a direction I wanted to go since it changes the shock angle, but for the time being, it has become a necessary one. I does clear the swingarm in all possible angles created by swingarm/suspension travel.
On the other hand, utilizing the 7R elbow would probably have a similar result in changing the shock angle. Rotating the top shock mount 180 degrees did increase the ride height slightly, but still not enough to utilize either the 12R or Kennedy 6R dogbones to obtain the desired ride height.
GOOD NEWS
Since I don't have a ready supply of "blank" dogbones or 6061 aluminum bar, I did take sledesigns suggestion and drilled a few holes in the 12R dogbones, just to see what kind of length would put me in the ballpark. The holes are neither clean or pretty (no pics will be coming), but they were at least equal and even. Good enough for "testing"purposes.
In estimated measurements, it appears that the '00 12R dogbones are 7.125"~7.25" from hole center to hole center. Similar to the stock 7R. The shortest setting on the Kennedy 6R dogbones is 7" and the middle setting is 7.5". It's starting to look like a length of approx. 6.75"~6.5" will be necessary to attain a ballpark of the desired ride height.
UNRESOLVED ISSUES
The location of the fork tubes in the triple clamps and the continues use of a 120/65 front tire have not been addressed at this time. Neither has to posibillity of using shims on the rear shock. The first objective is to get somewhere near a proper ride height.
After some testing in a "non-track" enviroment (read: "real world" - nothing personal Bart, just being practical), I figure that jonwright and I can fine tuning the ride height and start to address some of the other suspension issues and possible mistakes made on the brake caliper mount.
MORE INFO TO COME AS IT BECOMES AVAILABLE...
BTW - the 7R swingarm weighs approx. FOUR POUNDS more then the 12R arm. Go figure.
____________
There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.
-Ernest Hemingway
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ballisticzx12r
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posted April 04, 2003 10:04 AM
Edited By: ballisticzx12r on 4 Apr 2003 10:05
Sherm,
Nothing taken personally, if I did I would have never attended a GAP Trip. On the other hand you are putting though a case of information overload. I have not the vocabulary, techincial knowledge, tools, and where with all to do any of the above things you have figured out.
SHIT I DON'T EVEN KNOW WHAT A DOGBONE IS.
It is well worth the addional money spent to have that done with the compu-track. Let me know if you want my computrack sheet, I'm not sure if that would help you figure anything further out.
Do you have stickers left from the DG's I attended, need them for the new swing arm?
Bart
____________
Be fast and Be safe
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fish_antlers
Administrator
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posted April 04, 2003 10:06 AM
Red.... 6R and 12R dogbones are the same for an 00 methinks (I have a muzzy set in my garage)... they have 3 positions... you could try that as it would give you a good start (pardon me if Ive only skimmed this thread and you've already figured that out... I am late fer an appointment)
The other thing you could do is get a hold of Sagot.. .he is a cnc machinist/ tool/die maker... he has done this sort of thing before and made his own dog bones/ suspension setups etc... he may be able to helo you out.. .I will call him today fer ya and see what he says...
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ballisticzx12r
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posted April 04, 2003 11:26 AM
What the hell are dogbones?
____________
Be fast and Be safe
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