03 yz125 fork oil wt.?

[Wannabe250]

Recently rebuilt forks-new seals and bushings-and added fork oil as instructed in the manual to set height. Only thing I'm wondering about is the weight of the fork oil--I used a premium grade($9/liter) 5wt oil. Now it seems to bottom easier on the same or harder compression setting. :bang:

any thoughts appreciated :cool:

 

[BSWIFT]

Several ways to go here. Remove half of the fluid in each fork and add back a 10wt. This will approximate a 7.5wt. Going to a 10wt. will reduce bottoming but will give you some harshness. Depending on your weight and riding style it is difficult to give you proper advice, just generalities.
I use ATF fluid. I'm valved for wood and light MX, stock springs, and I weigh 155 lbs. ATF is cheap and is something simular to 7.5wt. I'm no expert and my explanation might not hold water but it works for me.

 

[Jaybird]

Mobil1 Synthetic ATF is a very popular fluid that will probably be the weight you want.

Seems to me that I can make much more difference in the action by changing the fluid levels. If you mix up riding between track and trail, you may want to consider sub-tanks.

 

[Wannabe250]

If you mix up riding between track and trail, you may want to consider sub-tanks.

What are sub-tanks?

BTW--I mainly ride tracks & rarely trails.

In full gear I'm weighing about 170 lbs.

I would estimate my riding ability 5 out of 10. :ride:

 

[BSWIFT]

Draw out half of the fluid with a piece of tubing attached to a sarynge and put back an equal amount of 10wt. Adjust the level from there to suit your comfort.
Sub-tanks give a greater amount of adjustability and plushness. Pricey but do the trick when properly set up.