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flyinguitars

Fork oil change (mobile 1 ATF)

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I bought some Mobile 1 ATF for my forks and Im gonna try to change the fluid this weekend. How much can I expect to use?...1/2qt...1qt..more..less? I just want to be sure that I have enough before I start. Also, I went back to some of the old posts to check the procedure. Does anyone have any good tricks for a fork fluid change?...This will be my first attempt.. One other thing...Im currently about 205lbs....Any recommendations for fluid height? Thanks for any help,

Mike

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Don't use ATF on new forks. It was fine 10 years ago. Use 01 oil from enzo racing or from yamaha or 5 weight fork oil if you can't find any. It is not hard to change. The manual is pretty clear. At your weight you might want run a higher oil level. Maybe 130 to 120 mm, but if bottoming wasn't a problem before, leave it at 135mm. They hold about 500cc in each fork.

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Use only fluid designed for suspension. Personally I like maxima. As far as oil levels, I need more info. What year is the bike? Do you have stock springs? What type of riding do you do? What is your skill level? Are you currently having any problems such as bottoming, head shake and so on? Sometimes it's best to have a suspension tech do it for you.They can spot potential problems they may come back to haunt you. It's 60.00 well spent.

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The bike is a 2001 yz426, the suspension is stock, and I ride mostly mx and I love to jump. I dont know how to rate my skill level, as I dont race, but I clear all the jumps at the track and am faster than 75% of the riders at my local track during practice. I was going to try the atf because I read good things about here and ii a few articles. I dont have any problems with the forks, I just wanted to change the stock oil.

Mike

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Mike, For what it's worth, I recommend you contact MX-Tech http://www.mx-tech.com/ with your questions. I had my forks re-valved by them and they used Mobil 1 ATF for the fluid.

I think they work great! Contact MX-Tech East. I'm sure they'll be more than happy to answer your questions free of charge. They were very helpful with me even before I discussed sending my forks in to them. Just my $.02.

------------------

00 YZ426F

01 TT-R125L (my son's)

74 Hodaka Super Combat(gone but not forgotten!)

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If your not having any handling problems, I would say you stock spring rate is just fine. As far as oil levels, 125mm to 130mm from the top will work for you. If you don't have a fork oil level tool, sears sells a small steel ruler that measures in mm with a stop on it.

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ATF will work just fine *IF* your forks are valved for it. Otherwise, I'd just stick with 5wt suspension fluid. I use Bel-Ray HV1 in all my suspension work for virtually all the bikes I revalve.

You need to run the oil level at 95mm to start. Anything less than that and you'll get some excessive bottoming over big landings. You *can* adjust the clickers stiffer but then it'll end up getting harsher. Remeber when measuring the oil height, you're actually measuring the air space on top of the oil. This means that 95mm is higher than 120mm.

------------------

MX Tuner

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my forks were also done by mx-tech and they used mobil 1 atf, if I remember right, and my forks work great. mike

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From all the differences in opinions, it is no wonder that there is not a "Right Way" or "Wrong Way" to set up your suspension. I like mine setup with 95mm oil height, .47kg springs, midvalve removed, Race tech gold valves & suspension fluid........I may even try bottoming cones for the big landings. Mark, I may back off the compression 1 or 2 clicks to see if I can dial in the stiffness.

It seemed to get stiffer as the track dried out last weekend ---- but oh so awesome.

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95mm is not high according to Yamaha. The range of adjustment is 150mm to 80mm. Seems 95 fits right in there quite nicely.

Dave, why are you thinking about bottoming cones? Did you have problems with bottoming? You never mentioned anything about any problems you were having.

------------------

MX Tuner

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Ah...the debate goes on.

My vote remains with a high grade 01 oil. I'm partial to the KYB from Enzo Racing for a lot of reasons.

However, if someone changes over to a thicker oil, be it ATF or something else, and claims the ride is better, then I'll trust they mean just that. My only argument against is in theory, not practice.

Also keep in mind that we have a wide variance in the style and types of riders on this board. No one setup will work for all.

Lastly, the only real mistake that I think applies to all styles of riding is that of a loose fork (one with little compression and rebound control). "Plush but firm" is the rule.

So whatever you do, apply some real world logic to what's happening up front.

DaveJ

[This message has been edited by DaveJ (edited September 26, 2001).]

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Mobil 1 ATF is fine to use on stock suspension, it is a little bit heavier than stock fluid.

If you take a look at the stock fluid in new WP forks, it looks, smeels, and feels just like Mobil 1 ATF.

The clickers will become more effective also with a heavier fluid.

Take Care....

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Mobil 1 ATF is fine to use on stock suspension, it is a little bit heavier than stock fluid.

If you take a look at the stock fluid in new WP forks, it looks, smeels, and feels just like Mobil 1 ATF.

The clickers will become more effective also with a heavier fluid.

Take Care....

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