these are one of the cheapest ways to raise the rear, it will lift it approx 45-50mm, sometimes more
http://www.ebay.com.au/itm/BLUE-PIT...77?pt=UK_Motorcycle_Parts&hash=item2a232556ed
you can sometimes run a longer shocker too, but remove the rear shock and measure it
also look at the bike and check all the angles with it raised too before you buy one.
it may make the chain rub hard into the swingarm, and eventually rub through.
i make my own from steel, they last a bit longer.
here is one i made for a mates PW80, it cant really be seen to well in the pic.
i asked him for before/after shots parked in the same postion but only got an after, he was in too much of a hurry to fit it, lol.
the bolt hole spacing on the actual block is around 35mm.
on most bikes, it will lift the rear of the bike approx 50mm