First of all I put my reading glasses on which makes life way more accurate these days!
I tend to use steel rules as I find them more accurate than tape measures. I have a good quality 600mm long one. I put two bolts through the eyes to transfer the center distances out to a place where I could lay the rule across.
I've just now gone out and re-done the process more accurately using two 10mm twist drills as they are a better sliding fit. I got 320mm.
What position the preload adjuster is on makes no difference to the unloaded length of the shock, just alters the amount of compression on the spring. It does change the ride height though as the the shocks resistance to taking the weight of the bike (bike sag) changes with each position.
15mm longer than stock shock length is a lot. I was running 14mm on the SV but have backed it off to 10mm now as swing arm angle was too steep. You may find it wants to turn in too quickly and tuck the front.
Lol, good deal, thanks!
I did about the same with two bolts, but used a tape measure.
I also thought the preload had nothing to do with length, but was grasping at any reason why my measurements were off by 3 mm on the N400 and maybe off by 1mm on the GSX-R shock. The GSX-R shock I spent more time measuring and re-measuring, and I feel like at the end of the day I gave it another 1mm or 2 in length stretching my measuring tape.
and......Right, but with the GSX-R shock at least 5mm shorter or more, it puts it at the 10mm or less of ride height out back.
So if I am 3mm short, the GSX-R shock is probably 310mm or 315mm length.
Where the N400 is 320mm
Dude I got the shock off, after going back and reading his eBay post says its 13" eye to eye, but not sure where he got those measurements!??! No way that is right.
Also keep in mind the GSX-R shock has an adjustable shank on the end, a claw style mount that mounts to the top shock eyelet which then mounts to the GSX-R with a threaded length and nut/washer so you can adjust ride height.
So lets review the numbers:
If its 5mm shorter than we are looking at 9-10mm rasied.
If its 10mm shorter we are looking at 4-5mm raised.
If its 10mm longer at 330mm, we are at 24-25mm height......and that is way too much. But I think this is all wrong.
Ohlins says 2011-2019 rear shock for 600 and 750, Hypersport TTX GP Shock is Length 319 (+2/-4) mm
-4 is 315mm, which I think this is their range of adjustment 315-321mm
I found this:
https://www.yss.co.th/downloads/YSS_ROAD_MOTORCYCLE.pdf
This shows the GSX-R 750 11-17 rear shock height 310mm-320mm, this must be their range of adjustment.
I would not see this company, YSS suspension which makes suspension for race bikes, going less than stock ride height out back.
It appears to be all road race application they make shocks for and no drag racing, which would or could require squatting the rear, or lowering it.
I am for now calling these measurements, unless anyone can argue, with valid exact measurements otherwise???
11-18 GSX-R rear shock
= 310mm
18-19 Ninja 400 rear shock
= 320mm
Flipping the upper shock mounting plates
= +15mm
11-18 GSX-R rear shock plus flipping upper shock mounting plates +5 mm ride height.
With the upper shock mount plates flipped, I mounted both shocks and tighten down the bolts, bounced the rear 5 times and let it settle and took measurements.
I measure the center of the axle bolt to a fixed point on my fender eliminator, actually the openings for the stock turn signals so I could rest the end of the tape measure on and in those openings. Then I held the tape measure to relive the weight of the tape measure hanging on it, but only enough to not effect the measurement.
Here are my numbers:
N400 stock shock: 22 13/16" - 579.437mm
GSX-R shock: 22 7/16 " - 569.9125
So almost exactly a difference of 10mm, which lines up with others measurements and my original measurements of 310mm on GSX-R shock (I had 311.5 but factor in + - 1mm) and the N400 shock at 320mm.
So we lost 10mm on shock height, and if flipped vs not flipped is 15mm difference, we are up 5mm in the rear. Although 10 might better, 5mm is better than less.
So we are at least 5mm up but no more than 10mm higher if any of the measurements are off on the difference in flipped and not flipped, but I did bolt those together and measure with digital caliper.