Time to do the front forks, just need a few clarifications

[New2Voyagers]

I read through the tech write up and I believe I can handle this rebuild fairly easily, however I have a few questions. Does the progressive swap out make this an airless system, or do I keep the air ride? Also It does not go in depth about replacing seals in the write up, so I have found this "rebuild kit" are these the seals I would need if I am leaking air and/or oil?

https://www.ebay.com/itm/401344290764?f ... R7TuhYrYYw


Also if the air is leaking from the lines itself, do they make a replacement fill line I can put in its place?

[triton28]

The kit you show with your post is primarily intended to be a rebuild kit for the fork slider bushings. It does NOT contain any of the #92049-1272 oil seals nor any of the 92093-1231 dust seals used at the connection of the chrome fork tube and the aluminium lower fork slider. The o-rings shown are universal kit add ins for some other make as the fork manufacturer, Showa, made these style forks for other manufacturers as well as for Kawasaki. The o-rings included may or may not be the same size as o-ring 92055-1364 I discuss below.
While using the part illustrations from either partshark.com or denniskirk.com or partzilla.com as reference, specifically the Front Forks and the Suspension/Shock Absorber illustrations, you will note that the rear suspension air lines apparently are still available as are the 5 tiny 6mm o-rings, # 92055-1100 which the lines use to seal against the metal fittings for the lines. I mention these 6mm o-rings because there are 2 of the same o-ring used on the front fork air line BUT for some reason there is NO part # given for them.
Also the air line for the front fork air is apparently still available. Do not overlook the Schraeder valves if one is experiencing a pressure leak as on the rare occasion they do leak, but it is rare.
On the front fork air system the air balance tube assembly uses 4 o-rings, #92055-1364, which are No Longer Available. These 4 o-rings often get lost or nicked when the fork tubes are removed from the triple trees so be careful with them during any R&R of the tubes. Having mentioned the NLA aspect, if one looks up o-rings at McMaster-Carr I would say that there is a metric size o-ring that would probably fit, albeit a tiny bit off possibly.
Generally it is the o-Rings and/or cracked air lines at the sharp bends in them which leak. If one has a good looking state of condition air line it would be advisable to change the o-rings and see if the system then holds pressure.
So to your original questions: yes in theory installing Progressive front springs does make the front suspension airless BUT, several posters myself included have kept the air lines and associated balance tube/lines/o-rings and run a small amount of pressure in the front forks. I tried zero pressure but I found I prefer about 5-7 pounds of air for the rough roads around here. YMMV.
I hope this long winded post has helped in some way,
Dave

[SgtSlag]

The 5-7 PSI is the OEM pressure recommendation for the front forks.

As stated, it is personal preference whether to use air in the forks, after installing Progressive Fork Springs: they are progressively wound, dual-rate springs. Air is not required, and it is more work, both in maintenance and upkeep (checking/maintaining desired pressure in the system; requires a low-pressure gauge and hand pump, like a bicycle pump -- NEVER USE AN AIR COMPRESSOR).

The Progressive Fork Springs are an upgrade, but they're not the best available option. They are relatively inexpensive, and easy to install. Remember to leave the metal cylinder spacers out of the rebuilt forks -- they're not needed, and they will make the forks excessively stiff.

Be sure to also upgrade the rear shock absorbers, as well as the Fork Springs: they work hand-in-hand, and upgrading one, without the other, will be very noticeable in handling. There are airless Progressive Rear Shocks, as well as Pressurized Shocks available, for the V-XII. Same thing here: airless are set-and-forget, simple, less expensive, but more limited in performance; they both have dual-rate springs. Get the heavy-duty springs if you ride two up a majority of the time; I did not, on my first set of shocks, and two months later, I ordered a new set, with Heavy Duty Springs -- still running the same pair, today, 10+ years later. Cheers!

[Nails]

When I installed Progressive springs in the forks, I plugged the ports for the air balance tube and dumped that whole assembly. I used JB Weld (backed up with a hose-clamp "bandaid") so it'd be easy to drill back out if necessary. If I had it to do over, I'd retain the air balance tube and attach a Schraeder valve in the simplest/shortest manner possible. I don't feel any need to add air -- I'd use it just to bleed off pressure from having too much fun on a hot day. But no regrets as it is ... which is simple. And fork oil doesn't splash into the air lines, filter unit or not.
Fortunately, my stock shocks still don't leak, and I'm quite satisfied with how they perform. I like being able to refresh the fork and shock oil.

[New2Voyagers]

Thank you guys for such detailed insight and personal remedies. I believe I have a decision made. I already replaced the back with heavy duty Progressive shocks, which when turned down halfway on the torsion plate rides really well in the back now. I'm 6'2" 290lbs so I opted for some extra strength for my arse even though I rarely 2 up. I think I will order the bushing rebuild kit and replace those while I have everything pulled apart, I will add the oil seals and dust covers as mentioned in the first reply. I will cap off the air lines and ride airless, I like the idea of less maintenance, less failure. One final insight and I will feel confident to do this properly....

Is there a secret on replacing the lower bushings? from the videos I have seen (mostly Vulcan rebuilds) they never show the removal of the bushings. It seems the top bushing will just slide right off the top once everything is apart, however the lower bushing looks as if it is "seated" on there and may require something more than hand strength to change out.

Thank you in advance for the replies!

[GrandpaDenny]

Something I experience with fork bushings is that they tend to not be very well made. Make sure you inspect them thoroughly before installing them, look for pits, roughness, etc. I don't remember if my mechanic says use only Race Tech or don't use Race Tech, I will check with him. Stand by for further message LOL

[New2Voyagers]

Something I experience with fork bushings is that they tend to not be very well made. Make sure you inspect them thoroughly before installing them, look for pits, roughness, etc. I don't remember if my mechanic says use only Race Tech or don't use Race Tech, I will check with him. Stand by for further message LOL

Hahahah will do...there's a BIG difference between ONLY use and DON'T use, probably best to wait

[GrandpaDenny]

Definitely Race Tech

[GrandpaDenny]

Definitely Race Tech