Going airless on the suspension?

[Eydugstr]

After owning this bike for a little over a year, still trying to come to terms with the suspension on it. The main issue I've got with the bike is the low speed wobble. Replaced the front fender bushings with Gene Kap's, which helped some, and replaced the front tire with an Elite III that matches the rear, but no real home run in improving the handling, but after some trial and error found out that the bike's handling really changes depending on the air supsensions' psi. Is it practical to switch to normally sprung rear shocks and do away with the air front suspension? Are there any pitfalls to avoid if I go this route? Bike is a '90 XII.

[triton28]

I have found that parking lot speeds will produce what seems like a wobble while turning the bike; this is just characteristic of a large heavy bike at slow speeds while turning and exhibiting the irregularities of the asphalt/tire wear patterns.
In a straight line at parking lot speeds there should not be any "wobble".
However, while driving on a public/private paved roadway at speeds of say 15 or 20 mph, and higher, one is then at the point of changing one's center of gravity to turn and not steering the bike with the handlebars as in the parking lot situation.
If one is experiencing that low speed wobble at roadway speeds, then it may in fact be the steering head bearing preload or lack thereof.
Don Medina, "HMB Don" and The Norcal Voyagers produced an excellent video that shows how to go about setting the preload on the steering stem taper bearings and I'll bet if you follow the video you may be surprised at the results. The video may be on YouTube I believe.
I would also suggest, if you have not already done so, changing to Progressive springs for the front suspension as the stock springs on all Voyager XIIs are at least 14 years old at the youngest, and yours if original would be 27 years old.
But the springs really shouldn't account for wobble as the springs function in the longitudinal direction, up and down along the fork angle, and a wobble is rotational in character so that is why I suggest the steering head bearing preload.
You may also have to experiment with differing weights of fork oil to find the one which works best for you
I can't comment on the rear suspension as I am still using the stock air shocks.
I hope I may have introduced some new ideas and that you find the solution,
Dave

[voyager55]

Progressive front & rear are way better than stock airshocks.
Get the rear spring shocks. You'll love the improvement in the ride & no more air to worry about

[Thud300]

Strongly considering this upgrade myself, starting with the rear. I've experienced a lot of bottoming out unless the air in the rear is above specs, currently mine sits at 40 psi.

[ghostler]

Eydugstr, sounds like springs are worn out or experienced age creep. There's a warning in the manual not to go above 71 psi, else may blow out seals, usable range 21 - 36 psi. I guess you could increase a touch above usable. I'd be concerned that if seals are old, they may blow out at a pressure lower than 71 psi.

Can't speak for the backs, previous owner replaced those with an expensive aftermarket air shock system, works fine. I guess he encountered same problem as you. In the fronts, he had 20 psi. Service manual warns against going above 36 psi to prevent seal damage, usable range 5.7 - 8.5 psi. I reduced front pressure to 8.5 psi. Got a lot of dive on braking, action was too soft on road bumps and dips, even got bottoming in a few cases. Until they repaved the road, section of US-70 on way to Portales had washboarding, bike wobbled really bad through that.

The Progressive springs corrected that, restored front height and smoothed ride action all around, became another bike. I followed the advice of others in the forum and found the Progressives a worthy upgrade, well worth the money spent.

[Eydugstr]

TY for the responses everyone. At some point in the bike's life the PO switched the stock air shocks to progressive air shocks, and routed the air line above (?) the frame just in front of the trunk, which became really noticeable when I installed trunk extenders for the g/f. So far the bike does okay if I keep the fronts at 8 psi and the rears at 33psi.

[Nails]

Get the rear spring shocks.

As many before me have noted, the stock rear shocks are vastly improved by by changing their oil. Not too difficult to do as routine maintenance every couple years. Some of us use a large syringe and blunt needle to get the oil into the shock. (Clean the syringe out later or the plunger will swell. Or just throw it away and use a new one every time.) Like many others, I also found that Dextron III works swell.

I bet Triton28 would agree that with fresh oil, there isn't much need to replace the stock rear shocks. The air-adjustability is useful to go from commute mode to tour mode, especially if touring two up. But from what I have read here, the air Progressives kinda suck. (Maybe that's what this quote is about.)

For my part, I don't plan to change the rear shocks before they die. Then I'll probably go Progressive (airless). But until then, I don't think the swap from stock is worth it.

The air forks are a whole nuther matter. I need more air than recommended to compensate for the weak springs (I can't get my bike on the center stand without help); and that compromises lots of other stuff. I look forward to this upgrade next year. I might go Race Tech instead of Progressive.