87' 430 fork oil weight?

[outdoorsman166]

Im putting new seals in soon and couldnt find a thread about what weight oil will work best for me. Im about 6'3" and 240lb most of my riding is on tight trails that are bumpy with an occasional long straight away. I dont jump very high and on average I would say speed is 25-50 mph. I have currently stock xc fork springs and Im leaning towards a 10 wt oil. Anyone similar to my size have a suggestion so im not buying $16 quarts of multiple weights?

 

[PEZBerq]

Get the springs sorted for your weight first. Stock springs will be too soft. Set the rider sag at 25 - 30% of full travel. Cut the springs down in length to stiffen them ( only by an inch or two to avoid coil binding risk) or else try Racetech for stiffer springs. 10W should be fine. Set up the rear spring also.

 

[rwgregory]

The info above re: getting your springs right 1st is correct. A good and inexpensive way to determine fork oil weight is start with automotive ATF. You can get it for 2 or 3 dollars per quart and it will be about 7 or 8 weight. If your fork action is too fast, (mushy) you can always go up to 10 or 15 weight fork oil.
FYI: I have used ATF for fork oil on many of my bikes with conventional non- cartridge forks for years with excellent results.

 

[Picklito]

FYI: I have used ATF for fork oil on many of my bikes with conventional non- cartridge forks for years with excellent results.

And I've used it in cartridge forks, too!

 

[justintendo]

i confess to getting good results with atf as well...seems to hold up a looong time too..

 

[husky jim]

I have been using ATF in all my convetional Huskys forks since 1985, with great results. It was recomended to me by the mechanic at Dirt Bike Headquarters. The local Husky Dealer at the time.

 

[Kartwheel68]

I use ATF in all damper rod forks also, cheap and works excellent. Most damper rod forks of the era, including Huskys, had too soft springs and too much damping. Slightly stiffer springs and lighter oil (ATF) makes a huge difference.

 

[oldbikedude]

Cut the springs down in length to stiffen them ( only by an inch or two to avoid coil binding risk)

Can somone explain this? I guess I'm confused by it.

 

[justintendo]

Can somone explain this? I guess I'm confused by it.

its an interesting concept, but the less coils a spring has, the stiffer it is...
say you have 2 shock springs..both same wire diameter, same length...but one has 9 coils and the other 7.....the spring with 7 coils will be stiffer..
the idea here is to remove a few coils and make up the difference with a spacer on these fork springs

 

[Motosportz]

I use ATF as well, works great and is very slick. Running 450ml in my XC500 and seems to be about right.

As for the cut the spring and it is stiffer deal the EZ way to get your head around this is to think about the spring uncoiled as one long bar. The shorter it is the harder it is to bend.

 

[suprize]

im a fan of ATF as well or mixing 1 bottle of 5 wt and 10 weight fluid to get the 7.5wt which seems best for tighter rutted, tree rooty stutter bumpy goat tracks but they tend to bounce in your face a bit from descent jumps.

 

[PEZBerq]

Can somone explain this? I guess I'm confused by it.

Yes. Imagine two springs of the same length - one with with lots of coils and one with few coils. The one with few coils will be a lot harder to compress.