New fork springs, new fork oil, no dampening?

[onchiman]

I just put in new Progressive Suspension fork springs and fresh fork oil on my '80 GS1000. Took her for a ride and it handles worse than ever, bumpy and jumpy. I took the forks off, re-checked the oil level. It's 15 wt spectro fork oil at 5 1/2 inches from the top of the fork tube with the fork fully compressed (as per the instruction sheet that came with them). There seems to be no rebound dampening on either fork. I push down on the upper tube and release and it springs up quickly with no dampening. What gives here?

[onchiman]

DOH!! Fixed it! I had accidentally refilled the forks with straight Dexron III ATF. I forgot I had mis-labeled/mis-filled the squirt bottle a while ago. I found the 15 wt fork oil and all is well. ATF is just too light weight.

[bwringer]

Thanks for the follow-up!

I couldn't begin to imagine what sort of exotic problem you might have had, so I was keeping an eye on this one.

On my bike's high-mileage forks, I've started mixing in about 10% "motor honey" to thicken up the 15W fork oil. I'm heavy and I ride fast, and it works great. Normal people with less fork wear, weight, and/or speed will be fine with straight 15W, but it's a trick worth knowing.

[JHawkins]

I am using 60% 30wt motor oil and 40% atf - I am heavy and ride hard, and it seems to be somewhere about right. I could perhaps go a little heavier, but not much more.

[onchiman]

And 100% ATF is a recipe for a great pair of pogo sticks! I'm sure it helped clean out the forks though.

[first timer]

if you want more dampening why not just get 20 or 25 weight fork oil. isn't fork oil formulated to keep froth at minimun, more froth less dampening right?

-ryan