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Fork oil 06.... pt 74

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This is really no big deal. In a previous thread we all taked about changing the fork oil in our 06 forks. I had the opportunity to really test the fresh-oiled fork this weekend.

The track was brutal. Washed out and burned out. Sprinklers had flooded MANY sections. The rest was blue-groove as maintained by a non caring state worker.

The forks were flawless. Consistency was much better than oem. This leads me to believe Yamaha , or KYB, may have done a piss poor job of bleeding the cartrige from the factory. I bled mine just as described by Eric Gorr in the Nov 2005 issue of Dirt Rider. The factory manual explains this pretty well. Be sure and read it..then read it again. Then read it once more with the cartrige in hand.

I ended up setting my outer chamber oil at 320cc's. This was a decent setting. I did bottom once...quite hard. I dropped the front end between two "woops"

I hate to call them woops. They were flooded and looked more like a flash flood. I added another 10cc's to the outer chamber. You can do thsi through the bleed hole in the fork cap. You do need a medical syringe...just inject the oil. Give it a few seconds to migrate into porper position.

Over all something simple really helped these forks. They are wonderful in stock form. This just makes them better.

I believe I will set the oil to 330-340cc from now on (just like you guys advised me to) and live happily ever after.

One interesting thing about this fork. It is quite easy to access the base valve. I may start playing with the valving. I dont believe the valving is much different than the goofy valving Yamaha has always used. The fork works so much better due to its excellent design and quality materials.

The stock fork is valved so ANYONE can ride the bike and have "working" suspension. This is everyoen from the 135lb pro to the 310lb beginner. The fork will work, but not be dangerous for either of these two riders. A setting with a more narrow range, say 180-210 will be much better for us regular folks. Its hard to blame yamaha, or any factory, for poor valving because they have to taylor it for unknown riders.

Has anyone else altered the valving in their forks?

If I do, I will post the specs here. The valving info I have is nothing paid for. Just info I was able to get from the various internet sources. I have specs from factory connection (labeled in my book as the wrist breaker) bbut I woudl not post it, that is unless the local medi-mart starts kicking back money for treating injured wrists. Their valving sucks. Very soft. Controlled by heavy springs. People THINK it works, but in reality they turn forks into pogo-sticks.

MX tech valving rules. I use something similar, but different. Mine were set up with the aid of Chad Harris at Miedoso Racing, Forslyk number 1 dude. He knows what he is doing. I will leave it at that.

You do need a special fork cap wrench to change oil. You also need the inside tool to seperate the fork caps. Total cost should be under 75.00 bucks for everything.

It sounds like a lot, but you'll pay for the tools with the first oil change vs taking them to a dealer.

Thsi does not include a seal driver. Seal drivers are wonderful ffor changing fork seals. The job becomes so easy with them that you feel liek you have cheated the system. I have no seal issues so I have not bought one in the 48mm size as of yet.

In summary, these forks come with "fish oil" from the factory. You'll never know just how good they are unless you get rid of the facoty oil after break-in. I know Yamaha recommends Kayaba 01 oil for them. If this is the case, why does the factory fill them with urine from "one-hung-low" when leavingthe asebly line?

Sorry for the typo's. I am typing without contact lenses again.

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So what oil did you end up using, the Kayaba 01 oil? Or did you try the synthetic oil?

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Yes you are correct, new fluid does make it feel smoother.

Mine were actually bleed pretty decent from the factory, but I know how it is... It all depends on which Jap Lady is working that assembly line on that day.

I noted after the fluid change the the forks bottomed a hair bit easier (fresher thinner fluid I assume). But that was nothing a tad bit of higher oil lever couldnt fix (settled on 340ML).

Valving... I personally think they are valved pretty good stock (onced tuned in). But I guess it all depends on your style and conditions. I mean if I was riding trails then yes, they would be in need of a revalve pronto! But for MX, I enjoy thier feel.

Interesting thing though is the 06 YZ125 I just picked up for my wife has AMAZING suspension. After tuned in the forks and shock are just freaken awesome. Where was this bike back when I was on 125's?

I have spent many days and many hours (to the point I was pissing people off because I wasnt really riding, just tuning) getting my YZ250's suspensions perfect (I have OCD), but in just 1 hour I was able to tune the YZ125 into a better suspended bike than my 250 (which says alot because to me my 250 is very good). But maybe its just because its so much lighter?

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