Yup, sure are. Front are progressive and rear is linear since the linkage is progressive.

Give me a second here and I'll dig up some links to the stuff I used for the rear...

Adjustable linkage rod:

http://t-rex-racing.com/catalog.php?item=517

It says lowering, but it will also raise the bike some 19mm, this is the same linkage I have in my R1 and the least expensive I've found. There was a guy selling one of these on the R1-forum.com for $55 I think. Not sure if he still has it.

Shim set I bought:

http://www.traxxion.com/Ride-Height-Shim-Kit-16mm/

I only used the red 2mm shim from the kit. Of course some stainless steel washers from the hardware store stacked to 2mm will do the same job for a lot less money. They need to be 16mm ID to fit the shock shaft. Any adjustments are about 2x, so 2mm of shims will add 4mm to the rear height. The linkage rod is 1.5mm thread pitch on each shaft end, one full turn will increase or decrease the length by 3mm and change the ride height by 6mm. I did a 3/4 turn to get a 4.5mm increase in ride height and shorten the linkage rod by 2.25mm.

Pic of the linkage rod on my bike when I initially installed it (didn't have the shim installed at that time), had a turn and a half on it to get 9mm of added ride height.



I can also dig up links to the linear SBU and Graves rear linkage setups, if you're interested.