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Whilst you are at it go look at pretty much any Ducati …916 onwards look at the rear suspension geometry make up in particular ..and how Ducati alter and or correct ride height…
They all have 1 tie rod to adjust length not 2 like you’re planning to use.
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Ughhh, I have to think everything over for you? It’s a parallelogram so if you’re off my even 0.1 mm you’re going to get binding in the linkage and ruin the whole system. It’d make more sense to cut various length tie rods and swap them out because at least you know they’re the same length. Notice that no one has done this simple and easy fix because it’s not simple and it doesn’t fix anything. And there’s a better (yet less convenient) way to adjust ride height without messing other things up in the suspension. But go for it!
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Andy can barely put together a coherent sentence and he thinks he‘s Gigiyou've already demonstrated you are not very good at measuring .. I understand now
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Also, if you’re that committed to the ease of adjusting ride height why not just have a 2nd shock that you can make adjustments to and swap in? You’re probably already spending $1k on these tie rods that are a complete bodge
Have I got this right, for the sake of clarity and perhaps towards a better solution than Andy is attempting re adjustable tie rods.
This is what we are looking at on the bike;
Not easy to adjust both sides if using suggested plan A, but provided you have something like an M8 fine pitch of 1.0 mm i.e. 1 turn = 1mm its pretty easy to be accurate with both sides but if not then as SD says its going to create all kinds of issues. Even exchanging tie rods look like a real PITA and forget any adjusting on a hot bike!
If you are swapping out shocks you may as well just adjust the one you have, I haven't had the pleasure of doing so yet but trust that is a matter of unloading it in such a way that you can get to the lower bolt, surely thats the simplest and cheapest solution. The XX99's absolutely spoilt everyone for ease of adjustment!
This is what we are looking at on the bike;
Not easy to adjust both sides if using suggested plan A, but provided you have something like an M8 fine pitch of 1.0 mm i.e. 1 turn = 1mm its pretty easy to be accurate with both sides but if not then as SD says its going to create all kinds of issues. Even exchanging tie rods look like a real PITA and forget any adjusting on a hot bike!
If you are swapping out shocks you may as well just adjust the one you have, I haven't had the pleasure of doing so yet but trust that is a matter of unloading it in such a way that you can get to the lower bolt, surely thats the simplest and cheapest solution. The XX99's absolutely spoilt everyone for ease of adjustment!
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View attachment 45511
Attaches completely differently than stock.
Not unachievable if someone knew how to use CAD
Proper - from a design perspective? Why is it better?
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Not to be pedantic but since Andy can’t do math, a thread pitch of 1 mm will get you 2 mm total/ 1 turn of rotation since both sides will be contributing to length. But relying on turns is a terrible way of measuring equal lengths accurately and precisely. Getting calipers down there looks pretty tough. The ride height also won’t be linear for each turn since the linkage is progressive. It won’t be 1:1.
The right way to do this would be to check everything over in Motospec. Until I see that, I’m not convinced that this’ll work. I don’t have to be an “expert” to be skeptical. You just need critical thinking and a little logic and math to see the issues that’ll arise with this.
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Well, ultimately, it's better because it's easy to adjust.
If you want to add one millimetre of ride height, pop the bike on footpeg stands, measure ride height, rotate adjuster, measure ride height, off you go. Or, just add one turn of ride height to the adjuster, measure afterwards. Can be done whilst rider is on the bike, in the middle of a test session.
With the stock setup, you either modify the bike in a manner to allow you to adjust the ride height. Or, remove the shock to adjust its length.
Sorry dont follow, you can get various pitches 1.25 is standard but .5 or 1 are common to our example of 8mm. If you made one turn on each tie rod then it would be as accurate as your spannering, but the change in ride height is not going to be linear as you say. However if you going to the trouble of installing adjusters then surely you would have a proper ride height caliper?
So whats easier? I am thinking that if you are well set up then removing the shock might save a lot of grief. I can see advantages for the tie rod solution during qualifying or between races but for track day warriors, I am not so sure!
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Ultimately, what you wish to change, is ride height.
Let's say, you want to increase ride height, by five millimetres. So, you measure ride height (with bike on peg stands).
Then, remove shock, add two millimetres to its length.
Reinstall shock.
Remeasure ride height. You've added four and a half millimetres of ride height.
Remove shock.
Add half a millimetre to shock length.
Reinstall shock.
Remeasure ride height.
Ride height is now five point two millimetres.
Etc etc.
With the shock on the bike, it's far easier to get exactly the increment in ride height you desire. And also, less time consuming.
Ducati don't give a .... about this, they just want cheap linkages and fixed length dog bones. Most customers don't adjust ride height.
Copy, re the tie rods my earlier observation re PITA I take back somewhat after having another look, its still fiddly and hot up there but If you made the rods adjustable from the top it wouldnt be too bad, you would just need to calibrate what one turn of the barrel equates to in height adjustment.
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In an ideal world, you'd just undo the lock nut on the bottom of the shock, and then adjust the shock length in situ. You can do this on most bikes.
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Or just get Motospec and you’d have the linkage curve and know how shock length equates to ride height. This separates the ride height from the linkage curve.
If the linkage is progressive and you adjust these dog bones you’ll be messing up the suspension kinematics. You’ll be starting suspension travel at a different point in the linkage curve as you adjust ride height
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