[jbbishop2]

Hi,

I recently acquired a 1979 CX500D in pretty good shape, with air shocks and air-assisted forks and a Windjammer 4 (I think) fairing. It also had notchy steering stem bearings, and in the course of installing new tapered roller bearings the little air tubes to the fork caps were broken. I have replaced the old tubing with new 1/8" tubing, which anchors in the press-in fittings nicely, but the system does not hold air pressure. The bike has been ridden about 100 miles with no air pressure in the forks (which I can tell you makes for an evil-handling motorcycle). Is there something obvious I'm doing wrong? Could the fork have been damaged by riding with no air? The first ride, the tubes were not replaced and fork oil spritzed out of the air tube stubs. Should oil be able to get to the air fittings?



If you have any insight I'd appreciate it. if this thing can't be made to handle pretty easily there will be a lot of parts for sale soon...



John

 

[Blindstitch]

I'm thinking that someone may have modified your non air forks. Do you have a picture?

 

[jbbishop2]

Thanks; I'll get a photo uploaded this evening. The input to this system is a Schrader valve clamped to the handlebar, with the 1/8" tubes running to the caps of the forks. That part doesn't look "Honda" to me, so you may be right about the modification. From the low-resolution diagrams at bikebandit.com what I have doesn't look like the 1981 air-assisted version cap, either.

 

[Blindstitch]

I know what you're talking about. I have seen a few. It's a mod to make them air forks but they aren't air forks. Most I have seen are broken.

 

[jbbishop2]

How have the ones you've seen been broken?



Photos of the setup on my forks:



[media]http://www.flickr.com/photos/[email protected]/4949802285/[/media]



[media]http://www.flickr.com/photos/[email protected]/4949799977/[/media]

 

[SteveinPA]

How have the ones you've seen been broken?



Photos of the setup on my forks:



[media]http://www.flickr.com/photos/[email protected]/4949802285/[/media]



[media]http://www.flickr.com/photos/[email protected]/4949799977/[/media]

Can you mount Schroeder valves to the fork caps where the red tubing attaches? You would have to fill the fork tubes one at a time but they would hold air. And yes, oil will squirt out holes in fork caps! Some have put spacers in their fork tubes to beef them up so they will handle more weight. I advise that you yank the forks and do a service on them. Clean them out and replace the oil with new fork oil in the proper quantity, add some 1" or so spacers on top of your springs, and stop those leaks so the forks will hold air. Air pressure is not necessary but may help with that fairing on there.

 

[jbbishop2]

>Can you mount Schroeder valves to the fork caps where the red tubing attaches?



I wondered that myself, but I don't see yet how to remove the tubing fittings.



>add some 1" or so spacers on top of your springs...Air pressure is not necessary but may help with that fairing on there.



That's good to know. I'd just as soon not have the air assist, so if I can get them working reasonably well with spacers over the springs and the air holes plugged I'd be happy. I personally hate that fairing...what a bunch of weight to hang off the front. I esteem Craig Vetter but I dislike this thing, as effective as it may be against the wind. If he were here I'd ask why the design has nuts that fall off inside the fairing cavity when you unscrew the mirrors, then I'd ask him to get his hand up in there to (a) find them and (

put them back on, 'cause I sure can't get my hand or tools in there..but I digress. Are the original headlights hard to find? I think they're really nice-looking pieces, myself.

 

[Blindstitch]

All of the units I have seen were broken. Pretty much shattered gauges. The caps are aftermarket and come in the kit.



The one problem with a broken system is if it is open air it will make a sucking noise. I would replace the caps with stock ones or drill and tap the current ones to plug them. I think that's what NateDawg did last year.

 

[Blindstitch]

I did just run across this for those looking to make air caps. Or maybe a way to modify what you have.



http://crfsonly.com/howto/230f/fork-air-valves/fork-air-valves.php

 

[jbbishop2]

>The one problem with a broken system is if it is open air it will make a sucking noise.



With the new tubes in there it doesn't make the noise, but when I air them up with a bicycle pump to about 25-30 psi, I can watch the pressure drop down to nothing in less than a minute.



>I would replace the caps with stock ones or drill and tap the current ones to plug them.



Drill and tap will probably be the choice, especially if I want to put individual Schrader valves in and keep the air assist. I wonder if just gluing the holes up with epoxy would work if I abandon the air and go with spacers.



Thanks for the help and the quick responses, you guys. I sure appreciate the insight.



John

 

[Blindstitch]

>The one problem with a broken system is if it is open air it will make a sucking noise.



With the new tubes in there it doesn't make the noise, but when I air them up with a bicycle pump to about 25-30 psi, I can watch the pressure drop down to nothing in less than a minute.





John

That's to much. Most forks for our bikes go up to 12 I think. The cx650 is only 6psi. Any more in these systems and they will either be to stiff or blow the seals out.

 

[jbbishop2]

>That's too much. Most forks for our bikes go up to 12 I think. The cx650 is only 6psi. Any more in these systems and they will either be to stiff or blow the seals out.



Thanks. I wish I'd known that but I got no book with the bike and I didn't see any thing in the pdf of the service manual about air-assist forks. Still, the seals aren't leaking, and that kind of pressure wasn't in the forks in operation; it bled off too fast.



Thanks also for the CRFsOnly link. Good technical information, and it says, "Never, ever, EVER use an air pump to ADD pressure to your forks. You could very easily damage the seals and/or internal parts by doing so."