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10mm? Wow! Mine are flush with the triple. My rear sag is at about 25 mm. No extra spacers on the clevis aside from the stock one, which I can't remember what thickness it is. I have an adjustable Ohlins but it's set at 339 mm eye-to-eye length which from what I've been told is the same as the stock shock.



Could be right, I don't recall what he did to his rear height. Might as well ask him. @PainfullySlo...what's your rear height set at, or at least what have you done relative to stock? And while we're at it how much did you increase your front height by?
Different bike though, so can't compare. On my 1198 I raised my rear by like 15 mm and the front by just a few mm (can't remember for sure but pretty sure it was less than 5). That helped on that bike for sure, but on the zx6r, like I said I was surprised with how twitchy it was when I got it, and raising the front 5 mm, while leaving the rear at stock height helped a lot. Still feels like it's on rails, and it turns in quicker than any other bike I've ridden and doesn't go wide on exit, and also doesn't put me in a tank-slapper when I get on the gas hard, which is nice lol

Then again, everyone's different, so what works for one person may not work as well for another.
lol I admire your cander SBK, you don't like to step on toes huh? You basically said "mmmm I think you're wrong, but let's ask Pslow just in case!" :wink
 

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lol I admire your cander SBK, you don't like to step on toes huh? You basically said "mmmm I think you're wrong, but let's ask Pslow just in case!" :wink
lol, no not all! I honestly don't know for sure. I thought I did, but you made me question myself, so thought I'd ask the source directly, that's all :) You may very well be right.
 

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Discussion Starter #23
Different bike though, so can't compare. On my 1198 I raised my rear by like 15 mm and the front by just a few mm (can't remember for sure but pretty sure it was less than 5). That helped on that bike for sure, but on the zx6r, like I said I was surprised with how twitchy it was when I got it, and raising the front 5 mm, while leaving the rear at stock height helped a lot. Still feels like it's on rails, and it turns in quicker than any other bike I've ridden and doesn't go wide on exit, and also doesn't put me in a tank-slapper when I get on the gas hard, which is nice lol

Then again, everyone's different, so what works for one person may not work as well for another.


I'll have to have a play around and see where I get, when I first got the bike the ohlins damper was set to soft and it was twitchy as fuck, soon as I took it up 7 clicks the bike was lovely. I feel very planted on the bike for sure. But now I'm starting to get serious about starting racing I need the bike tonne as good as for this year so I can work on all my techniques comfortably.


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I'll have to have a play around and see where I get, when I first got the bike the ohlins damper was set to soft and it was twitchy as fuck, soon as I took it up 7 clicks the bike was lovely. I feel very planted on the bike for sure. But now I'm starting to get serious about starting racing I need the bike tonne as good as for this year so I can work on all my techniques comfortably.


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Post some on-track videos later on! It'd be cool to see some of the BSB tracks that I've seen only on TV. You guys have some pretty nice tracks there, especially for bikes....and you don't have to drive like 12 hours to get to them.
 

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Discussion Starter #25
Yer I have brands hatch just up the road so is great. Although this year they aren't doing that many open pit lane days for bikes! Theres only 4 in the calendar at the mo. I am going to install the go pro 5 on the tail this year to get some good footage of how I progress. Haven't got any track videos of me yet, i will be logging all this year though for sure. And now with the camper it will be easier to bring a lot of stuff and can also get the mrs filming fly bys from track side.


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I agree that Andi0 needs to be very careful adding an 8 mm shim while having that much of the fork tubes prodruding above the top triple clamp! You do realize that adding an 8 mm shim will raise the rear ride height at least DOUBLE that due to the shock linkage. I added a 6 mm shim to the clevis of my '12 (stock shock length 339 mm) and it raised the rear above the axle over 14 mm, causing me to "tippy-toe" with my feet now; 32 in inseam. Oh, and my forks were lengthened 15 mm by the Racetech kit, and lengthened another 5 mm by running flush with the top triple. I know it's not the same bike, but ...

Finally, the comment by the OP about the "twitchiness" of the front end until the steering damper was turned up implies the rear is too high relative to the front already. You shouldn't use the damper to cover up an underlying problem. I even watched a YouTube video recently by West coast suspension guru Dave Moss to the same effect: you should fix the problem of the head shake being caused by the bike's geometry before utilizing the steering damper.

If the OP's rear shock spring is too soft and the rear is sinking down excessively I can see ... but if not the raising of the rear end should proceed with extreme caution; especially at track pace. Just be careful...
 

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Discussion Starter #27
I agree that Andi0 needs to be very careful adding an 8 mm shim while having that much of the fork tubes prodruding above the top triple clamp! You do realize that adding an 8 mm shim will raise the rear ride height at least DOUBLE that due to the shock linkage. I added a 6 mm shim to the clevis of my '12 (stock shock length 339 mm) and it raised the rear above the axle over 14 mm, causing me to "tippy-toe" with my feet now; 32 in inseam. Oh, and my forks were lengthened 15 mm by the Racetech kit, and lengthened another 5 mm by running flush with the top triple. I know it's not the same bike, but ...

Finally, the comment by the OP about the "twitchiness" of the front end until the steering damper was turned up implies the rear is too high relative to the front already. You shouldn't use the damper to cover up an underlying problem. I even watched a YouTube video recently by West coast suspension guru Dave Moss to the same effect: you should fix the problem of the head shake being caused by the bike's geometry before utilizing the steering damper.

If the OP's rear shock spring is too soft and the rear is sinking down excessively I can see ... but if not the raising of the rear end should proceed with extreme caution; especially at track pace. Just be careful...


I always listen to feedback and will only try this setting, if it's no good I'll go for a thinner spacer. I will ride try ride try! At the beans day on the 23rd there is going to be some suspension specialist so throughout the day I will get there assistance with the setup and hopefully dial it in.


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I would really recommend going and having an experienced tuner set up your bike. Just kinda guessing at it based on what someone else has done who may or may not not have any idea what they are doing can get your bike all screwey pretty quick. You have to set the rear ride height based on the swing arm angle you need. That's just a physical property there is no other way to get around, then once that is where it needs to be you have to move the front to get rake/trail to where it needs to be (to make it all oversimplified). Which is how people end up with fork extenders. But, in order to get all that right you really need to know what numbers you are trying to achieve and someone who makes a living setting bikes up will know what you need to get too. Then you are in the ballpark and can make small adjustments from there if you really want to.

Since I'm doing this today I figured I'd add a quick tip: use a 16mm nut instead of washers. Mine is 6mm thick instead of the stock 2mm shim, but this allows me to adjust it to anything I'd like without taking off the entire clevis
Uh, might not be an issue but the threads were not meant to take the load like that... you check they will be ok and not strip?
 

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Discussion Starter #30
I would really recommend going and having an experienced tuner set up your bike. Just kinda guessing at it based on what someone else has done who may or may not not have any idea what they are doing can get your bike all screwey pretty quick. You have to set the rear ride height based on the swing arm angle you need. That's just a physical property there is no other way to get around, then once that is where it needs to be you have to move the front to get rake/trail to where it needs to be (to make it all oversimplified). Which is how people end up with fork extenders. But, in order to get all that right you really need to know what numbers you are trying to achieve and someone who makes a living setting bikes up will know what you need to get too. Then you are in the ballpark and can make small adjustments from there if you really want to.







Uh, might not be an issue but the threads were not meant to take the load like that... you check they will be ok and not strip?


Like said above I will be getting assistance when at the track from a suspension specialist. I'm not one to jump into anything until the full knowledge is there.


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I would really recommend going and having an experienced tuner set up your bike. Just kinda guessing at it based on what someone else has done who may or may not not have any idea what they are doing can get your bike all screwey pretty quick. You have to set the rear ride height based on the swing arm angle you need. That's just a physical property there is no other way to get around, then once that is where it needs to be you have to move the front to get rake/trail to where it needs to be (to make it all oversimplified). Which is how people end up with fork extenders. But, in order to get all that right you really need to know what numbers you are trying to achieve and someone who makes a living setting bikes up will know what you need to get too. Then you are in the ballpark and can make small adjustments from there if you really want to.



Uh, might not be an issue but the threads were not meant to take the load like that... you check they will be ok and not strip?
It's tightened all the way down so I'm not worried. The benefits are more for testing, if I adjust it while I'm at the track and like the new adjustment, I would fill the gap with washers later.
 

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Geometry differences between 09 and 13

Fork height / shock shim

09-12 zx6r
5mm / 4mm

13+ zx6r
7mm / 2mm
So assuming the other components that determine height, like forks, swing arm, shock linkage, are the same for both models, what that is telling me is that the 2013+ is just a tad bit lower from the factory. I wonder what the difference in rake angle or trail is.
 

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It's tightened all the way down so I'm not worried. The benefits are more for testing, if I adjust it while I'm at the track and like the new adjustment, I would fill the gap with washers later.
Haha, well yea when it's tightened down its basically the same as spacers. It's when it is adjusted up and you've got 1000lbs going into the 6mm nut on the threads who's original job description was "hold the hanging weight of the rear wheel and swingarm assembly" that I'd be nervous. But I have no idea what grade that bolt is and the last time I had to worry about a problem like that was in college, what, 7 years ago haha?
 

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Haha, well yea when it's tightened down its basically the same as spacers. It's when it is adjusted up and you've got 1000lbs going into the 6mm nut on the threads who's original job description was "hold the hanging weight of the rear wheel and swingarm assembly" that I'd be nervous. But I have no idea what grade that bolt is and the last time I had to worry about a problem like that was in college, what, 7 years ago haha?
1000 lbs?? Damn, you better get on a diet? How are you even so damn fast pulling all that weight?? :laugh

I actually have a spreadsheet I made at work a few years ago for a project I was working on with calculations for max tensile load on bolts (or any threaded rod), and I can tell you the threads on that rod will take many thousands of pounds to shear off (assuming no side load, just tensile). I remember at the time I made those calculations, it was for just a 1/4" bolt. Can't remember if it was fine threads or coarse threads, and I'm about 80% sure it was just a grade 5 standard black oxide bolt, and it turns out it would take over 3000 lbs to break it. Basically you could suspend a small car from just a 1/4" bolt. The one from that shock is closer to like 1/2". It would take well over 10,000 lbs.

Now, you start adding any side loads, and induce bending and things are much different. Adding that nut will be ok, although I don't see what good it does, because you'd still have to pull the seat, tanks and anything else there to adjust the top nut every time you want to make a change, so I don't see how it saves any time really. If I'm understanding his intentions well, he's replacing the shim with a nut, basically sandwiching the attachment point on the frame between 2 nuts. So if in the future he wants to raise the height he can't just turn the bottom nut clockwise because it's already tight. Will have to loosen up the top nut. If he wants to lower, then he could turn the bottom nut ccw, but then there will be a gap between them and the shock clevis will just be bouncing up and down, so still need to get to the top nut again to re-tighten. Doesn't really save any time in future height adjustments, but the nut will work just as well a spacer.

All I know is the TTX shock makes it much easier to adjust height :D
 

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Theoretically it should still be much easier than removing the clevis completely to add washers. Yes you still have to take the seat off to get there but you can leave the shock untouched and just adjust the upper and lower nuts.

Think about it, if you can leave the shock bolted, you don't have to support the bike by the frame in order to unbolt the shock and clevis just to add a couple washers.
 

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1000 lbs?? Damn, you better get on a diet? How are you even so damn fast pulling all that weight?? :laugh

I actually have a spreadsheet I made at work a few years ago for a project I was working on with calculations for max tensile load on bolts (or any threaded rod), and I can tell you the threads on that rod will take many thousands of pounds to shear off (assuming no side load, just tensile). I remember at the time I made those calculations, it was for just a 1/4" bolt. Can't remember if it was fine threads or coarse threads, and I'm about 80% sure it was just a grade 5 standard black oxide bolt, and it turns out it would take over 3000 lbs to break it. Basically you could suspend a small car from just a 1/4" bolt. The one from that shock is closer to like 1/2". It would take well over 10,000 lbs.
It's 2017 you can't mock me for being fat! I just figured, super rough numbers, you got something in the neighborhood of 550 lb/in spring rate in the rear, annnd close to 2 inches of travel seems like a reasonable amount of movement... its-o-facto 1000ish lbs.

These can vary from company to company, but here's an example from one particular manufacturer:

Proof Load Tensil Strength For Grade 2, 5, & 8
Well there you go, can you tell I don't ever have to work with bolts and what they can hold together? haha
 

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It's 2017 you can't mock me for being fat! I just figured, super rough numbers, you got something in the neighborhood of 550 lb/in spring rate in the rear, annnd close to 2 inches of travel seems like a reasonable amount of movement... its-o-facto 1000ish lbs.

Well there you go, can you tell I don't ever have to work with bolts and what they can hold together? haha
That's a reasonable ballpark, super rough numbers...except for the 2 inches of travel. The seat might drop that much, but the spring doesn't compress as much...due to the linkage geometry. Remember, you corrected me on that not too long ago ;)
 

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Theoretically it should still be much easier than removing the clevis completely to add washers. Yes you still have to take the seat off to get there but you can leave the shock untouched and just adjust the upper and lower nuts.

Think about it, if you can leave the shock bolted, you don't have to support the bike by the frame in order to unbolt the shock and clevis just to add a couple washers.
That's true, but how easy can you access that nut? Can you fit a wrench in there over the shock to twist it? Just asking. Idk, I've never tried it personally, just feels like it'd be a PITA.

Putting a couple of jack stands under the pegs and dropping the bike down on them takes like 30 seconds, so that's not a problem. And if you use the U-shape spacers that someone mentioned, you wouldn't have to remove the clevis at all.

But why are you even doing this? Don't you have a TTX that's adjustable?? :D
 

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That's a reasonable ballpark, super rough numbers...except for the 2 inches of travel. The seat might drop that much, but the spring doesn't compress as much...due to the linkage geometry. Remember, you corrected me on that not too long ago ;)
Ooops, goddammit. Duh haha.
 
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