I've got a standard, so all I had to deal with is my aftermarket Samsonite bag hardware.
The rear shocks of my 1982 GoldWing Standard had given up the
ghost! Taking a speed bump at anything greater than a walk would
cause the rear suspension to bottom out no matter how much air
was in the shock. The shocks held air, but they no longer had any
hydraulic damping.
I first intended to replace the shocks or rebuild them. I looked
at Progressive Suspension replacements at over $300, then at their
rebuild kits for $150. An attempt at buying the rebuild kit had
them backordered without any known delivery date. I thought about
non-air alternatives, but felt that it would be a step backward to
remove that functionality from the bike.
Finally, I checked out my shop manual, and while the Clymer manual say
they are not rebuildable, the Honda shop manual gives instructions for
replacing the seals and refilling with oil - just like the front forks!
Checking the exploded views at Bikebandit pointed me toward ordering a
pair of seals for the units. They arrived in just a couple of
days.
My camera fooled me and didn't take all the pictures I pointed it at -
so I'll try to explain what the camera missed.
I've got a standard, so all I had to deal with is my aftermarket
Samsonite bag hardware.
Ready to pull the shocks. Notice the yellow stain on the
differential? I thought that it was a leak at the drive shaft
joint while it was actually a stain from the shock oil leaking on
it. The Honda manual describes removing all the air line plumbing
back to the filler. What I did was loosen the fitting while the
shock was still on the bike then just turn the shock off of the air
fitting after pulling the shock off the bike.
My
local independent shop suggests using only Honda seals. The pair were
just under $30 including delivery from Bikebandit.
This is really a photo from my fork rebuild page, but the technique is
exactly the same. Remove the circlip and washer (I modified a big
circlip plier from Harbor Freight). Removal of the
seals needs
air pressure and the Honda manual says to add a tire valve to the
air hose inlet and pressurize them that way. I just used a
rubber tipped blow gun. Honda says to put the boot back on the
shock, hold it upside down in a vise and wrap it with rags while
blowing. That's a good idea because it will make a BIG mess even
when you do that.
My shock on the drive side barely had any oil left in it. The left side
had maybe half of its oil. Holding the shock upside down will
allow some to drain out the air fitting hole after pumping it some.
With the air line hole plugged (I used a short length of fuel line and
a screw) you hold the shock upside down in a vise and refill with
12.5oz of oil. The Honda manual suggests ATF, but I used 15 wt
fork oil, since that is what my local shop had suggested for my front
forks. Look at how much oil that is compared to what came out!
I used a length of 1-1/2" PVC tube to drive the new seal back
into the shock.
It worked as a wonderful
slide-hammer, and I didn't have to worry about scratching anything with
metal. (This is really a shot from my fork rebuild)
Bike's back together and rolling now! I ran right over to my
favorite patch of speed bumps and the shocks WORK again. From
walking out into the shop until the first shock was rebuilt and
remounted took 1.5
hours. The second shock only took .5 hour total. I was back
inside and washing my hands in 2.5 hours, and it would probably only be
2 hour job now that I've done it once. Seals and oil was less than
$35. Maybe I won't wait 20 years before I do it again!
The '83 and later shocks have heavier springs, so I don't know how
that would effect the shock disassembly. Let me know and I'll add
some notes.
That's all I know. If there's something that should be added, tell me: chuck@kichline.com