Vintage Dirt Bike Q & A

What do you guys think?

5wt, 10wt, or 15wt. I'm 200lbs. I also have some 15wt on hand.


Thanks!

~Craig

I researched this once and came up with this chart:

http://www.peterverdonedesigns.com/lowspeed.htm

If you read entire thing closely, it appears that the ATF originally used in these forks comes closest to modern 15 wt fork oil, depending on brand.

However, I've found 15 a little stiff and I mix 15 wt with a little bit of 5 wt, to get something close to 12 wt (I think). That works for me, but evertime I change it, it is slightly different because I am using a ratio rite to mix it and I'm sure I never get it exactly the same. But, it's close enought I don't notice the difference.

Some people use 10 wt, some use 5 wt and some use 15 wt. The amount of oil you put in makes a difference too.
Experiment with the 15 you have and see what you think. You can always drain and put in 10 wt. Or just go buy some type F atf and put it in.

Fair enough. Thanks for the info!

-Craig

Just to let everyone know, I ended up using 10wt Bel Ray fork oil. I still may experiment with other weights and brands, but for now, the fork feels great! I went up to 11,500ft and did a rocky pass road with great results. The fork didn't bottom out, and it seems like there is still some left in it if I hit something really hard. This is what the fork should feel like.

-Craig