redelk
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posted April 04, 2003 11:51 AM
 Edited By: redelk on 23 Apr 2003 21:49
These are dogbones (located near the bottom of the shock) - the Kennedy 6R/9R adjustable and the OEM 12R
This is the OEM dogbone after the drilling of the hole. It's now .875" shorter (or an estimated raise in ride height of 1.75").
I couldn't find two pics at the same angle, but I think you can get an idea of the difference. The one on the right is of the "slammed" setup.
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redelk
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posted April 04, 2003 11:55 AM
Edited By: redelk on 4 Apr 2003 12:50
Bart, maybe you could check yours for me and see if it's drilled or is just the OEM dogbone (has "1163" stamped on it). Also, it would be nice if you could find out EXACTLY what they did to the brake caliper bracket. My other "source" of information turned out to be woefully incorrect.
Depending on how well you perform these simple tasks, will have a direct effect on how much effort I put out in finding any old DG decals.
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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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ballisticzx12r
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posted April 05, 2003 08:23 AM
Sherm,
This is the best I can provide...
He used the stock "12" Dogbones, no modifactions to them at all.
The caliper carrier was machined to remove material because the ZX_12r hub is wider then that of the ZX-7r.
We stayed with the ZX-12 caliper although my understanding is there is no difference between the two.
I am sorry but I don't have a camera to be able to take the pictures and send them to you. Again I am not smart enough to figure out the uploading process.
The bike is now having the swingarm powder coated, we didn't have enough time before my track day.
If you would like I can give you the number of my tech, if you promise not to keep him on the phone for hours I'm sure he would help.
Bart
P.S. Is that good for my stickers?
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redelk
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posted April 05, 2003 09:45 PM
Not yet... grap your suspension set up sheet.
1. What was the STATIC (not "free") sag for the front and rear?
2. With the bike on the both stands (so the bike is basically level), measure the distance from the TOP of the axle (not the nut, the actual axle bolt) straight up to the bottom of your tail section. Make sure your measuring tape is going STRAIGHT UP (90 degrees in relationship the garage floor).
What is that distance?
3. Have they done this swap on a '00 or '01 ZX-12R?
Since many parts and where they affix to each other are different on the '02 and '03 models, what works on the B series might not apply to the A series. Then again, it might be the same.
I would love the number of your tech, but at this stage, I'll wait. I would have to talk to him for at least an hour to answer the large number of very specific questions I currently have. I need to narrow down the scope before I make that call. I'll e-mail if I get to that point.
I think I have found one or two of DG2 and DG3, but I can't seem to remember what I saw in my toolbox today. Your answers to the first two questions (F & R sag and "ride height"), might even make me look a little harder.
Tomorrow, weather permitting, will be the first shake down ride of any major distance (200+ miles).
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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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redelk
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posted April 06, 2003 06:17 PM
Last night, jonwright and I set the static sag on both of our 12Rs. All in hopes of fine tuning our bikes' suspensions today. Weather did not "permit". Today's high was around 45 and heavy thundershowers all day.
Both ends of my 12R were within the "suspension bible's" recommended street settings of F-30~35mm/R-25-30mm (F-32.5mm/R-26.5mm). Our "sag session" did produced some weird results on my RaceTech sprung forks with 5 wt. oil.
It seem that any adjustment to my fork preload (up or down), would increase the static sag above the original setting. The L2 and L3 measurements would change each time we made adjustments. It would be lower then the base numbers when we increased the preload and vice versa when we decreased it. Since the L1 measurement changed as well, all of the adjustments resulted in a increased sag.
When I fill out the RaceTech "suspension survey", it says the sag should be 32mm on both ends. Of course, that is if I also had RaceTeck valving as well (which I do not). The only changes I have made is to raise the nitrogen pressure on the rear shock from the OEM 143 psi to 200 psi, moved the forks up 8mm in the triple clamp, heavier springs with lighter weight oil in the forks (5 vs. 7.5) and a 120/65 front tire.
Anyone got a idea as to why we were got these results?
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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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GOZR
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posted April 06, 2003 06:56 PM
Edited By: GOZR on 6 Apr 2003 20:07
This mod was made first on my friend Michel's Extrem Zx12 #102 at Le mans's race in 2001 with a model zx12 2000.( the swing was a 1996 ) The number 2 is mine( swing 99/2000 ).
RedleK.. 
I'll get my notes when i'll finish my moving to my new place. it's lost somewhere in a box
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redelk
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posted April 06, 2003 10:15 PM
Thank you very much, GOZR!
Since our testing day got rained out, I've went ahead and took off the peg brackets and all the attached hardware (pegs, shifter, brake pedal, etc.) to get them powder coated as well. Even though everything should be ready by Wed., I'll probably be too tied up with a district advertising convention (our AAF club is hosting it) to even mess with it till Sunday, at best. 
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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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Ballisticzx12r
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posted April 06, 2003 10:47 PM
Scarey Late Night Post.
Sherm,
I also had my shocks completly redone, I think they used Hyperpro valves and springs ( I know this must simply drive you mad, that I don't even know these things). As for the 00 or 01 verses the 02, I have no idea as to them doing the doing the same mods on the earlier bike. I will offer the following, I'll get a copy of the computrack sheet fax to me and forward it to you. Since I don;t have my bike currenlty the measurements you requested are no a reality. Furthermore the difference in the 02 general dynamics would lead me to believe, it is useless to you.
I am also putting the galfer wave rotors on the front and when I have it back, I'm more then happy to measure until the cows come home.
Barto
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redelk
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posted April 06, 2003 11:05 PM
That cool, Bart. I still would like to have the static sag and ride height measurements from your '02.
Static sag numbers are "universal"... kinda (I'll spare you the "specifics"). Shock and fork valving and such really don't change those type of numbers. Type of riding does (i.e. road course racing has lower sag numbers like around 25~30mm both F & R).
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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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ballisticzx12r
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posted April 07, 2003 09:47 AM
Sherm,
I just got off the phone, with 4 & 6 racing is thoughts are as follows...
Whatever I send you is not in anyway going to help you set your bike up, the 00 & 01 verse the 02 has many more changes then anyone wants to seem to mention.
He also said that with truly computracking your bike you will never get it "Optimzied" now I know you are lightyears advanced of me in this stuff. But your time is worth something, think about having it done.
I'll call you today at your office and fax it down.
Bart
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redelk
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posted April 07, 2003 11:50 AM
My time might be worth something, but my "employers" might not agree with you on it's "true" value. Since they are the ones who write my paychecks the odds of me having the bucks to have anyone work on my suspension is about as high as my stuffin' Mark and Rick on the Foothills, letting them pass me and stuffin' both of them again... all before we even got half way to the lake.
Can we say, "Less than ZERO"?
Unless I win the lottery without buying a ticket or ya'll start a "Fix Poser Elk's Suspension Fund"... I'm pretty well on my own.
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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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jonwright
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posted April 07, 2003 08:09 PM
c'mon Sherm...you know you like messing around with yer bike....
By the way, I wondered in an earlier post if the 7R swing arm would make the bike more wheelie prone.
YEEESSSSS!!!!!!
Even in lower RPM's when it starts to climb the tach I see sky. It snaps straight up, like a souped up Gixxer 1k or something. I have to say it rather took me by surprise. Yeah, in second gear.
First gear? Shee-ot. Right a 6k I'm wondering how that cloud formation looks an awful lot like Elvis.
On my bike (with stock gearing and exhaust) it's a nice, slow rise and doesn't come up at all in 2nd gear roll ons like Elk's bike.
My bike will stay on the ground unless you want it up. Elk's will take judicious use of throttle to keep the wheel down. But I think he keeps it under 6k rpm in the twisties anyway... 
Hey Elk, notice how much fork tubes you see on top of the triple clamp in the picture??? Looks like it's lowered quite a bit if I'm seeing fork tubes there.
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redelk
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posted April 07, 2003 08:12 PM
Edited By: redelk on 7 Apr 2003 21:21
You see the NAME on those tubes?
I figure I'm sticking with the 120/65 for now. I might think about raing the forks up a mm or two, but after our "sag session", I'm not so sure I want to even mess with it till I get a few miles on the current configuration.
I'd still like to shorten the chain so I can move the wheel up a little more, but that too will have to wait until I get the new chain and sprockets. Now, it comes down to just getting a chance to ride it.
____________
There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.
-Ernest Hemingway
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jonwright
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posted April 07, 2003 08:25 PM
Look, you just need to sit down with some of the Clinton croneys that I KNOW you know, and get lessons on embezelling so you can buy those Ohlins forks and get someone that knows what the hell they are doing to set it up for you.
You know you wanna....
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jonwright
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posted April 07, 2003 08:34 PM
And FURTHERMORE:
I believe Elk's anality has been well documented, but did you notice in the first picture:
The location of the master link? A coincidence? I think not.
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redelk
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posted April 07, 2003 08:44 PM
A better example would be the last pic and where the master link is located (left pic). It just happened to line up with the valve stem.
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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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Zhooligan
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posted April 07, 2003 08:57 PM
Personally I find the pink flamingo a real addition to picture. It is positioned perfectly in the photo.
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MikeM
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posted April 08, 2003 06:33 AM
Guys
Just throwing in my 50 cents worth, what GOZR says is his compadres' bike raced at Le Mans has a ZX7-RR, not R, swing arm fitted. This might have an effect on how suspension ratios etc work out.
I can offer some advice on working out linkage ratios. Back in the late 80's/early 90's I was involved in the early full suspension mountain bikes and used to speak to people like Mert Lawill and Horst lietner about how they worked out their suspension systems. This was in the days before FEA existed for the average person. What they used to do was take a large piece of wood, draw a grid on it and using card board, drawing pins etc make a simple working side elevation of their swingarm and shock linkage (either 1:1 or to scale). Using the grid you could plot the rear hub path and this let you track the shock movement. If you wanted to alter ratios or rates etc you simply cut a new bit cardboard and retried the measurements. If it worked for them designing from scratch, for you where you can measure a ZX7 for the relevant dimensions this might be a simple and cheap way of solving the whole problem.
Regards
MikeM
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redelk
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posted April 08, 2003 07:01 AM
Thanks of the idea, MikeM. The 7RR swing arm is actually about a 1/4" shorter then the 7R arm and was a little bit more of a "shortening" then I really wanted to try out. It seems that the real trick to all this has been getting the 12R wheel assembly (wheel, brake caliper bracket, axle coller, etc.) to actually fit inside the 1/4" narrower gap of the 7R's swingarm.
The issue of ride height adjustments seems to have been addressed in different manners between GOZR, myself and Bart (with a completely differently arranged '02 12R). I'm starting to believe that there might be more then one "right" way to deal with it, but I might be the only one that has taken the "change the dogbones" route. I don't know for sure.
What I do know is that in my case, a few things I did not first imagine had to be changed to have the OEM shock both clear the shock opening on the 7R arm and attain a preferred ride height. I was happy to see that my rear static sag was pretty close to what I was wanting after I changed the dogbones.
It's just that only after a few test rides will I know if I find the possible change in the spring rate and other suspension action aspects are to my personal liking. Only then will I be able to pursue a direction of finalizing the hole location of the dogbones or consider other methods, such as shims and such.
____________
There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.
-Ernest Hemingway
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MikeM
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posted April 08, 2003 09:31 AM
Redelk
Looking at the picture of the Le Mans racer they appear to have got around the dogbone problem by using a threaded adjuster rod with rose joints either end. I would guess that they used a pair of oppsoite threaded joints with a pair of threaded lengths and machined centre section (like a top link in a race car wishbone suspension setup) with which you can adjust the length of the dog bone. It's interesting that this whole subject has come up because about 12 months ago I tried several times to contact Scratch Moto in France to get some more details about their 12 racer with no replies.
Without plugging some figures into my laptop's FEA program I can't be any more specific but if the swingarm is 6mm shorter then you are going to lose about 1% of your rear wheel travel assuming that all other components have remained the same. You have kept the 12 rear shock and "elbow" which would be somewhere in the region of 2.5% to 3% oversprung now so I would increase the rebound damping a couple of clicks. Now due to the 7 swing arm Dogbone pivot point being lower in relation to the centre line of the swingarm you have reduced the vertical component of the "pull" on the elbow. So my guess would be that you have reduced the amount of rear wheel travel available. Might is suggest removing the rear shock and removing the spring from the shock and refitting it and see how much rear wheel travel you actually have? The percentage recuction in travel over standard should give you a starting point for springing and damping adjustment.
I'm still hung up on whether to get the standard swing arm braced and get an Ohlins shock or get a 7 swing arm (like the sound of the fast turn in but not sure about it holding a line in corners) with 7 rear wheel and associated bits and Ohlins to suit.
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redelk
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posted April 08, 2003 09:56 AM
Could you e-mail me at adcraft@sbcglobal.net with what measurements you would be needing? I understand that to get an accurate picture, it would require quite a few measurements and I think that I could provide them to you. At least for the parts and pieces I do have. I don't have a P series 7R "elbow" or dogbones, so I could not tell you what the angles or distances are on those. You might have to "coach" me on what reference points you wish me to measure from, but I'm a fairly quick "study" in such matters.
When I spoke with Victor, we did discuss adjustable dogbones similar to the ones on the race bike, but sadly, I'm trying to do this on a shoestring budget and the expenses of those dogbones, as well as a aftermarket shocks and such (7R wheel, etc.) are just beyond my current means.
Removing and refitting the spring on the OEM 12R shock might be beyond my skills. I have not looked that closely, but if the spring can not be easily removed from the bottom side, I don't see how it could be done with out taking apart the top part of the shock. Would it be possible to just loosen the two collar nuts completely and reposition the spring?
Believe it or not, I have not actually posted my "full report" on this project. I planned on putting everyone here to sleep on a new thread when I finished.
____________
There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.
-Ernest Hemingway
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MikeM
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posted April 08, 2003 12:17 PM
Red
The FEA package I have works on definite X/Y/Z corordinates and my laptop doesn't have the power to accept a wide range of variable dimensions. I have a '00 12 and a friend has a Zx7R so I will take a look and see if I can get any useful dimensions. There is a way you can do this without resorting to technology.
If stripping the spring from the shock is out of the question you could remove the shock - measure its legth from top mount to bottom eyelet (you need the full extended length to allow for negative travel - sag - when the wheel follows road contours) and then measure the length of chromed damper rod, visible between the coils, from the bottom of the shock body to the bump stop. Support the bike so that the rear suspension is free to move and place a jack under the rear wheel/axle. Cut two lengths of string - one the full length of the shock and the other the full length less the dimension of the chromed rod - giving the compressed length of the shock. Jack the rear end until the first length of string reaches from the top shock mount on the frame to bottom shock mount on the "elbow" - record the dimension vertically from the floor to a datum point on the rear axle centre line. Jack the rear end up, making sure the rest of the bike doesn't rise, until the second, shorter, piece of string stretches between the top and bottom shock mount. Record the vertical distance from the floor to the same datum point on the rear axle. Subtract one from the other and you have rear wheel travel, subtract the length of the shorter piece of string from the longer piece of string and you have shock travel. Divide one by the other and you have the wheel/shock travel expressed as a linear ratio.
The factory manual gives you a measurement for rear wheel travel - and you know the shock travel. Work out the original wheel/shock ratio as a linear ratio. If the two are within 2-3% I believe that the shock would work well enough with the oem spring weight, but don't count your chickens yet.
You now need to work out an aproximate rising rate ratio for the oem suspension set up, and then what you have fitted with the 12/7 hybrid.
Draw a simple X/Y axis graph where X is "rear wheel travel" and Y is "shock length". Lower the back end down to the extended length you recorded in the first step and start this as 0 on the X axis and mark the shock length as the starting point on the Y axis. Then in 5mm increments jack the rear end and record the gap between the upper and lower shock mounts (the effective shock length). When you have completed this you should have a series of marks on your graph, equally spaced on the X axis and unequally spaced, but not by very much I would guess, on the Y axis. Draw a smooth free hand curve passing through all points on the graph. The measurements themselves aren't as important as the shape of the curve as this is showing the rising rate of the shock linkage. Repeat this process for both back ends and then overlay the curves. Are they the same? If they are then you are in luck as the OEM shock, and spring - if the first part says so will do the job. If not, then my advice would be to contact one of the suspension specialists who others reccomend (I can't help here as I am in the UK) and give them the info and they will be able to do the neccesary.
As far as adjusting your rear ride height with the bike unweighted I would try to split any adjustemnts needed between the shock length - if adjustable like on Ohlins- (or shimming the upper mount) and altering the length of the tie rods (dogbones) so as to keep the linkage ratio as close as possible to the mid point of it's movement (they become steeply rising and falling rate at the extremeties of their travel). I would have thought that you could make the rose joint tie rods for under $100 and I would say these were the way to go.
Hope this helps.
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ballisticzx12r
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posted April 08, 2003 01:58 PM
HOLY SHIT AM I LOST......
Sherm,
I hope the computrack sheets help.
Bart
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redelk
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posted April 08, 2003 05:35 PM
MikeM, that might just be my Sunday project if I don't get to ride. I will be busy with business "stuff" all this week through Sat. night anyway.
Though I'm no "expert", I am fairly familiar with "X & Y stuff" since I have worked with computer generated vectored (what we call "points & curves") graphic artwork since the mid '80s. You could say that "X & Y" are good friends of mine, but I spend the majority of my time working in a two dimensional plane (no "Z's" except when I sleep). As a matter of fact, my graphic files have a "PLT" extension. Though AutoCAD uses the same extension, my program's files are slightly different, but the principal is almost the same.
To layout what you described on my program would be extremely easy and far more accurate then if I was to attempt to "draw it out" by hand. They try to keep me away from sharp objects (i.e. pens and pencils) anyway.
Kennedy sells adjustable dogbones like you mentioned for $135, but even that amount is stretching my budget. Yeah, I know... some folks would be thinking, Why bother with such a project if I was neither willing or able to spend the money on it?. The way I look at it is that's just part of the "challenge". Just to see if it can be done.
Bart, your third page did not come through. It was just a smudge down the middle of the page.
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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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Ballisticzx12r
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posted April 14, 2003 09:37 PM
what the fuck??????
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