99 yz400f fork oil capacity and weight

7 replies to this topic
  • mediumdaddy

Posted July 23, 2012 - 02:15 PM


I'm about to order seals and tools to do my forks, but i need to know how much oil to get - and what weight - not sure if it matters really, but what weight should i get? what tools besides the seal driver and bullet and the fork oil level tool thing? Thanks!

  • grayracer513

Posted July 23, 2012 - 03:42 PM


The fork level tool thing isn't necessary. Handy, maybe, but not required. A vernier caliper will work, as will anything you can use for a dipstick.

Remember that you do not need to remove the base valve or damper cartridge to do this job.

You will need somewhere around 36 ounces of oil, so get two quarts. Any good quality 3-5wt FORK OIL will work.

  • mediumdaddy

Posted July 23, 2012 - 04:31 PM


Is that 36 oz per side? And i was just going to use the rocky mountain vids as a referance- thatll work right? Never done this before. Any good tips?

  • grayracer513

Posted July 23, 2012 - 06:16 PM


No, not per side. It will take just over one full quart to fill both sides to the right oil level. There is no specified quantity to install to, just a level measurement.

Never seen the RM video, but it's probably fine.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • mediumdaddy

Posted July 25, 2012 - 04:52 AM


Thanks for the help. hopefully i can get this done. These are cartridge type right?

  • grayracer513

Posted July 25, 2012 - 07:21 AM


They are a single chamber, open bath cartridge fork, yes.

  • mediumdaddy

Posted August 06, 2012 - 05:46 AM


Thanks for the help Gray. I did this project about a week ago, and it was a LOT easier than i had anticipated. My bike is a whole new machine now. Not at all squirrely, and the PO had the forks set at 25 clicks in. Holy crap! I backed it off to 20, and then off more to 10. I'm still fine tuning, but they were stiff as heck. i wonder if thats what caused the seals to blow?

  • grayracer513

Posted August 06, 2012 - 06:35 AM


No, it's not. The fork seals are not exposed to the pressures created within the damping cartridge. Adjustments are made by turning the clickers all the way IN (tight, down, clockwise, etc.), then counting clicks OUT. This gives a repeatable reference from the point at which the adjusting needles in the assembly bottom out. Remember that you have two such adjusters, rebound on top, and compression under the bottom.

Related Content


Chubby dad, looking at bikes , First trip to the orange/black forum ! by Slow_ride

Dirt Bike   Make / Model Specific   KTM   250-530 EXC/MXC/SXC/XC-W/XCR-W (4-Strokes)
  • Hot  28 replies
WR Camshaft Swap Info - last post by jamesm113

WR Camshaft Swap Info

  • 0 replies

yz400f throttle bog by yz400fmaniac

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • * * * * *
  • Hot  28 replies

Is it worth it? (Cam and High compression piston) by macgi77

Dirt Bike   Make / Model Specific   Honda   CRF 150/230 F/L
  • Hot  36 replies

Michigan Motocross Tires by 288yz450

Dirt Bike   Dirt Bike Regional Discussion   North
  • 1 reply

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.