Oil coming out of the front fork air fill valve

[dirtbike13]

hello all I have a 99 voyager XII and I have some oil coming out of spreader valve when checking air pressure?

[Nails]

I see a question mark, but no real question.

I think the filter disk at the top of the fork internals is intended to minimize oil backing into the air line. Any that does anyway will collect down at the Schrader valve in the fairing.

I "fixed" this with Progressives and completely eliminating this air-line plumbing -- I plugged the holes in the fork tubes with JB Weld. If I had it to do over again (it wouldn't be very hard to drill out these ports; and I saved the manifold), I would keep the manifold installed and put a pressure-relief valve on it (to bleed off unwanted pressure after playing hot and hard). I'd also look into making this drain back into the fork tubes.

As an aside, this plumbing increases the fork's headspace volume. I think this is why fork-oil level recommendations cited here are higher than what the manual says. Once this plumbing was removed, I went back to the level listed in the manual.

[GrandpaDenny]

I "fixed" this with Progressives and completely eliminating this air-line plumbing -- I plugged the holes in the fork tubes with JB Weld. If I had it to do over again (it wouldn't be very hard to drill out these ports; and I saved the manifold), I would keep the manifold installed and put a pressure-relief valve on it (to bleed off unwanted pressure after playing hot and hard). I'd also look into making this drain back into the fork tubes.

Dude, there you go overcomplicating things. All you have to do is push in the valve and phft excess pressure comes out. I've discovered that keeping a valve cap on prevents building up much pressure as well.

As an aside, this plumbing increases the fork's headspace volume. I think this is why fork-oil level recommendations cited here are higher than what the manual says. Once this plumbing was removed, I went back to the level listed in the manual.

You've got it backwards, Nails. The measurements are taken from the top of the fork down to the oil level. 140mm for stock, 145 recommended by the guys here on the AVA for Progressives. I recently had my forks rebuilt, and 145mm is way too high. I've been bleeding out small amounts of oil at a time by pulling the valve core and pushing down on the handlebars. I've just about got it right. Next time I change the fork oil I'll give you guys a good measurement.

Progressive's instructions recommend as a general guideline if the bike manufacturer's specs aren't available to run between 160 and 190mm measured down from the top of the fork tube. Perhaps that's why some guys run ATF or similar really light fork oil, because they're running a fork oil level of 145mm and it's way too high?

[dirtbike13]

Thanks for the reply, are you saying that it may just be oil backed up in air line? I'm going to change my oil in them and want to make share if there is something going bad I would like to address it at that time. I all so have progressive springs upgrade so is it a good idea to remove air line and plug holes ? Or leave the air lines in places?

[GrandpaDenny]

Thanks for the reply, are you saying that it may just be oil backed up in air line? I'm going to change my oil in them and want to make share if there is something going bad I would like to address it at that time. I all so have progressive springs upgrade so is it a good idea to remove air line and plug holes ? Or leave the air lines in places?

I noticed a little oil coming out when I bleed the excess air pressure out of my forks. I also have Progressive springs. Since the swap to Progressives eliminates the spacer and filter, like Nails said, I guess there's nothing to keep a little oil from blowing out when bleeding pressure off. It's a miniscule amount, however, there really isn't much oil in the forks to begin with, something like 3 1/4 oz or so IIRC, maybe 3 1/2. A 5mm drop in oil level is a teaspoon full of oil. I don't think it's a good idea to remove the air lines and plug the holes. One reason for keeping the air lines in place is once I get the suspension dialed in just right for riding solo, when I ride two-up I can add a couple of pounds air into the forks.

I also left the air lines in place when I replaced the rear shocks with Progressives. No real reason to spend time and effort removing them - what difference does half a pound of rubber make on an 800 pound bike (plus 300 pounds of rider in gear)?

As long as you keep changing the oil in the suspension regularly (every two years is recommended IIRC), the OEM forks and springs work just fine. I replaced the front springs because the old ones were worn out and sagging, and OEM springs cost a hell of a lot more than Progressives. Similar reason for why I replaced the rear shocks - it was cheaper and easier to replace with Progressives than to rebuild the OEM ones that had gotten blown out.

[dirtbike13]

thanks for the the help grandparent makes me feel much better that that that small amount of oil was ok. I will change the oil in them.I do also like the idea of leveling air lines in places I like to be able to adjust the ride

[SgtSlag]

If you install Progressive Fork Springs, you will not need any air added to the system... Progressive Fork Springs are dual-rate springs, eliminating the need for air assist.

If you find 8 Wt Fork Oil comfortable, you can use Dexron VI ATF: equal to 8 Wt. Fork Oil; full synthetic (VI only; III/IV/V are not synthetic); lasts twice as long (four years, instead of two); and it is typically less expensive than a quart of Fork Oil.

Fork Oils maintain their viscosity over their entire temperature range, never varying. Dexron ATF does the same thing: retains its viscosity within its entire temperature range. Dexron ATF is also highly detergent, keeping your fork innards squeaky clean between changes.

Many OEM's used Dexron ATF in their fork assemblies, from the factory, during the late 1970's onward. Cheers!

[AHOY]

When I put a gauge on rear valve, it reads nothing. When I try to fill with air it seems like it doesn't want to go in, and sometimes I get a squirt back of oil. Any thoughts?

[GrandpaDenny]

As an aside, this plumbing increases the fork's headspace volume. I think this is why fork-oil level recommendations cited here are higher than what the manual says. Once this plumbing was removed, I went back to the level listed in the manual.

Lower. Distance is measured from the top of the fork to the top of the oil level. More distance = lower oil level. Also, fork oil level recommendations are NOT different than stock for stock springs - the standard 140mm. The level you're thinking of is for Progressive springs, which we've managed to come up with a level of 145mm.

[buzzcut]

Mine spurts a bit of oil also with the progressives but....I have struggled with the way the front end handles on this bike...historically always ran 40 psi on front tire. Progressives' went in... hoping for improvement. Still no joy. added 3 lbs of air...no joy. added more...no joy. went to 34 on front...no air...no joy...added 3...no joy. added 8 again with the progressives and front tire at 34 joy joy joy...just my 2 cents. 7.5 synthetic in forks at 145mm from top. Took a year of riding to sort this out. time to share

[GrandpaDenny]

Things to check to cure the wobblies:

1. Front fender bolts.
2. Steering head bearing
3. Tire condition
4. Wheel bearings - pull the calipers off to check!

The wobblies aren't usually caused by the suspension. Having said that, though, oil level too low can cause wandering at high speed.

What tire are you using on the front?

[buzzcut]

the Michelin 3. I have ridden sport touring for 40 years so this bike has taken some time to sort out for me. Everything else checks out ...I am replacing the wheel bearing next spring though too.

[buzzcut]

from previous post, in discussion with my mechanic, I don';t have heavy enuf fork oil. I need more damping. Always ran 15w on my connie and she was 600 lbs. this one is seven hundred....dont know what I was thinking with 7.5w. However. just switched it out to 15 and whole different bike. wow. Front end solid now:)