I get asked incredibly often how to choose variator weights. This is a tricky question, because the weights you choose depend a lot on where your bike is in its path to Voodoodom. Nearly any bike will get improvements by going to sliders from rollers.
A stock bike might work well with 11g sliders, while a heavily modified bike may have anywhere from 8g sliders to 14g sliders, and everything in between.
I'll show you here an easy way to choose the weights that will be best for your bike.
Assuming that you want a good balance between acceleration and top speed, you want a weight that will get the variator belt all the way to the top of the ramp as quickly as possible. Lighter wieghts will give you more off the line acceleration, but will not let the belt reach the top of the variator ramp, so you loose out at the top. Heavy weights will give you a bit more rotational mass at the variator which lets you squeeze some extra speed out of the top end, but you loose out at the line.
To get the best balance, first take apart your variator. Then take a dark colored marker and fill in the top inch to inch and a half in a square. Then re-assemble the bike and go for a ride. Choose a spot where you can try to make a run for your top speed on flat ground.
Then go home and take apart the variator again. You'll notice that the belt has rubbed off the marks you made as high up as the belt traveled. With any luck, you'll be just a few milimeters from the top. If thats the case, your weights are perfect. If you've still got a long way to go, then get heavier weights. Too sluggish off the line? You probably went too heavy.
On a near stock bike you'll want to start around 11g. For a modified bike with a heavy (1500RPM or above) contra spring, 12g or 13g is a good starting point.
Leave a comment