Fork oil level

[mmaddog]

Hey guys, I've got a quick one. I got some "new" forks for the bike I dumped last month. I was just wondering if anyone would be willing to share the fork oil amount that should be dumped in them with me. I'd appreciate it, and thanks guys.

[bonanzadave]

A cup in each one. 8 oz each. Probably gonna vary model to model.

[salty_monk]

I think it's 140mm from the top of the leg without the spring fitted.
To get the level cut down the straw on a spray bottle trigger to the right length & pump out any excess.

Dan

[mmaddog]

I wonder, if you go slightly over, do they just get super stiff or do you endanger the seals. I'm not in the mood to shell out money for progressive springs, but i'm 225 lbs and I could use a little extra stiffness as I have a rather aggressive riding style. Just ask the ford escort I tried to drive through that's causing all this. haha.

[bonanzadave]

I'm not in the mood to shell out money for progressive springs, but i'm 225 lbs and I could use a little extra stiffness as I have a rather aggressive riding style.

Dude, I dont know what machine your on but dont compromise your equipment for a few bucks. You can use some heavy oil in the forks but its a bandaide for weak springs. Break the piggybank and get the progressive springs. For your saftey and the handling of the bike its money well spent.

[Mark whiz]

I have an old Article on fork setup from Motorcyclist magazine that I still use today. Their recommendation is to bring the oil level to 6 inches below the top of the fork with the fork fulled compressed. This is just a tad bit higher than what Suzuki recommends for my GS700 - but is has worked really well over the years.

Small changes in fork level make big differences in the springing preset of the fork. I played with mine a couple weeks ago when I changed out a fork seal and I set the level at 5 5/8 inches and at 285lbs, that is a bit too much preload for me.

I do use light oil (5W) but that tends to affect the rebound more than preload. Lighter oil gives better response over groups of bumps, which can be important depending on your riding conditions.

So for you, I'd suggest the 6 inch level and see how you like it. If you have air assist on your forks, try to keep that down below 10psi, as air tends to just make the forks "sticky" - but you can play with the pressure to find what you like best with that 6 inch oil level.

[salty_monk]

You can add bigger spacers to the top of the springs for more preload or even job them & add a bigger spacer to change spring rate.

To be honest the steel is going to be tired, anything you do will be a band aid as all springs lose their "memory" eventually.

The progressives are a great upgrade.

Dan

[Nessism]

You can add bigger spacers to the top of the springs for more preload or even job them & add a bigger spacer to change spring rate.

To be honest the steel is going to be tired, anything you do will be a band aid as all springs lose their "memory" eventually.

The progressives are a great upgrade.

Dan

Adding spacers does not increase the spring rate, just the preload which increases ride height.

Cheap and effective trick to increase spring rate is to pull the springs and cut off a couple of inches of coils. Make some PVC spacers to replace the lost height - if there is a stock spacer make one long one out of PVC and ditch the stocker. 15W fork oil is about right for our GS bikes. Good low buck trick and only costs a few bucks for a chunk of pipe.