ZX6R Shock Upgrade


Read up on the shock swapping possibilities ( The How to NOT cut the battery box  and the SV rear shock compatibility chart ) for a 2000 SV650S and purchased a ZX6R shock, 2009 - 2012 vintage via eBay. Spring rate (per Racetech) is 9.2 Kg/mm (stock 9.1 Kg/mm) and length is 339mm (stock 337 mm), with adjustments for preload, rebound damping, and low and high speed compression damping - lots of knobs to play with.

The calculated spring rate per Racing Suspension Products  is pretty close.

FYI, my weight is about 84 Kg., riding is all street, no track. I personally think stiffer springs front and back are primarily for bike attitude control under heavy acceleration and braking on smooth surfaces, i.e. racing conditions. My interests are more for comfort on bumpy roads and road holding in bumpy corners, so the front stays at the stock 0.7 Kg/mm (with emulator knock-offs), and the rear spring rate stays close to stock, but now with adjustable and hopefully more sophisticated damping.


Still on the side stand:

Pop onto jack stands under footpegs:

The ZX6R shock bushing is ~30mm wide at the top, and the shock flange inside dimension is ~30mm wide at the bottom, a perfect fit for the SV650.

The flanged 10mm lock nut came with the ZX6R shock top bolt, which was unfortunately at 51mm just a smidgen too short for the ~45mm outside width of the flange. The metric junk box had an M10 x 60mm bolt which was hacksawed down to 55mm.

The SV650 knuckle where the shock attaches has more space to the dogbone on the left than the right. The shortened bolt is 61mm long including the head, and the bushing between the dogbones is 68mm, so there's ample clearance as long as the bolt head is positioned to the right, and the thicker lock nut to the left.

The lower shock flange bolts to a 30mm bushing inside a needle bearing and it is free to move side-to-side a bit. There was still plenty of clearance to the dogbones at both extremes of the bushing position.

Lowered the battery box with brackets, custom bent from 3" mending plate to give about 1.75" space, allowing the battery to clear the shock by about 1/8".Trimmed the battery holder thingie off the tank hinge with a hacksaw. Drilled a couple of holes in the back of the battery box and zip-tied the battery to the back of the box.

Initial settings (from the ZX6R 2009 manual):

  1. Rebound - 15 clicks counterclockwise (of 21) from full hard (clockwise)
  2. High Speed Compression - 3 turns counterclockwise (of 4) from full hard (clockwise) (outside damping adjustor, 12mm wrench)
  3. Low Speed Compression -  3 turns counterclockwise (of 5) from full hard (clockwise) (inside damping adjustor, flat head screw)
  4. Preload - spring length 179mm

Rear Sag:

At the recommended 179mm spring length, a reference measurement was taken with the bike up on the jack stands (no load on shock). With the bike weight supported by the paddock stand, the unladen sag was 15mm. Then with my weight added, laden sag was 40mm.

These figures are about 5mm high and were corrected with a ~2mm tweak in the preload, changing spring length from  179mm to ~177mm. Sag figures are now a happy 10mm unladen and 35mm laden. The preload can be adjusted on the installed shock.


This was an Ottawa winter 2015/16 garage project, and I thought riding and on-the-road evaluation would have to wait 'til Spring. But . . .

Incredibly good riding weather today (Dec. 24th, 2015) in Ottawa, Canada. 17 deg. C. and sunny, a bit windy.

Tried out the newly installed ZX6R shock, seems to be working fine with the chosen sag and default damping settings. Better compression damping over low speed bumps, not much more harsh over our larger potholes. In comparison, the old Gen1 shock seemed dead, transferring jolts directly to the derriere.

Also able to ride on Dec. 25th (Merry Xmas) and 26th, and that just reinforces first impressions.