Changing fork oil, someone help!

hi, i have an 01 yz426 and i am going to change my fork oil for the first time. first of all i have no idea which weight of oil i should use and which brand is the best?? and i am really iffy on the changing part of it. don't wanna mess anything up if you know what i mean. so any help would be greatly appreciated. thanks again.


Have the manual with you, it will take you step by step through the process. It's a very good reference. Also save yourself some headaches and get (or make) one of those oil level tools. It's a strait pipe connected to a syringe so that you can suck the oil out to the specified level. If you have the right tools then it's not a bad job at all. As for oil type, I personally used the Yamaha Suspension oil '01' as recommended in the manual and it works great (a little pricy though).

If you do a simple change (don't take it completely apart) then just remember that once you get the cap off and the spring out that you will have to dump the oil then pump the damper rod then dump the oil then pump the rod...etc... a bunch of times to get all of the oil out. Have fun!

Use Silkolene fork oil. It's every bit as good as the Yamaha (Kayaba) fork oil and is much cheaper.

Go to your local dealer and get the tool that will install the seal. You can get it from Motion Pro or Progressive Suspension. If you have the time, hang your forks upside down overnight to make sure you get all the oil out, if not you can pump them. Also, go ahead and get the "bushings" that go inside the forks. If they are not worn too bad then you will have them for the next time when they are. If at all possible, get a buddy that has done seals before. Once you see it done, you will realize how easy it really is.


Call me a simpleton, but I too use the Yamaha Suspension oil as recommended. What I do to measure the oil hieght is use the squirter(sp?) (or trigger?) from an old squirt bottle (like an old windex bottle). I measure off whatever hieght I want the oil level to be, say 100mm, then mark the pick-up tube on the squirter a 100mm from the bottom of the pick-up tube. Then just hold the squirter's pick-up tube in the inner fork tube keeping the mark level with the top of the outer fork tube (with the fork completely compressed of course) and pull the trigger until no more will come out. You may also want to place an oil pan on an elevated up-side-down bucket (or something) to "shoot" into.

I would also recommend a fork driver as will need one for 45/46mm forks (I believe), but if you can't get one, it's been suggested to me (I haven't tried yet) that you can use the old seal (behind the new one) to carefully bang against to drive the seal. But money (about $60~$70) and time (trip to local Yami-shop) willing, I still recommend getting a fork seal driver. It saves a lot of time and worry :) .

Hope this helps!

[ April 03, 2002: Message edited by: kozmic ]

:) Dont By yamalube 01 it is so freaking expensive, the = is anything in 5wt so the Yamalub 01 = 5wt other brands.

Personally I think that paying anything over 5 bucks a pint 4 fork oil is a joke. I buy yamalub 5wt its 3.99 a pint. I change the oil about every 6 mnths or 4 hard rides. I mean Hard rides....But thats just me, some guys change once a year Period...

Oil is a tricky subject it is also a prfrence (Riding style), Some will put in heaver oil the like the slow rebound, some light softer and so on. I would say stay with the 5wt or 01 if you want to pay 36 bucks for 19 oz's man I used to buy skunk.... a never mind.

Follow the manual instructions, get a turkey baster or Fork Oil Gauge. The manual is real clear. And ask around at the local tracks, the goons at the shop will think yer a moron, But We know better.


I used the Enzo 01 oil - it's way cheaper than Yamaha. My suspension tuner uses 7.5 wt oil and that's what I will use next time.

HEre is a good thread on how to change the oil: click here

Regarding the posts about seal drivers. Good advice, however I don't think that Pete wan'ts to change the seals, only the oil. No need to get those tools to change only the oil. :)

Oops....sirthumper is correct....sorry?

Don't know why I assumed he wanted to change the seals? Although if you were going to completely disassemble the fork (to clean the bottom end out too) it might be a good time to replace them as well....

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