1983 GS850GL Forks Leaking

[Wingsconsin]

Right hand side (as seen from bike seat) has oil leaking out through the top past the dust cover. I presume that means I need new fork seals ..?

I have looked on the Z1 website and found the seals and new dust covers are available. However - I spoke to a service manager at a local dealer about it and he said that I will need the "bushings" also ? An upper and lower bushing..?

Any advice on this for a novice fork seal replacement ?

I don't even know what I don't know...

Part numbers, places to buy the parts and tutorial information are all welcome as I have never done fork seals before -- but it looks like I am going to ....

Thank you in advance

[Chris G]

should be no issue getting seals I just got a decent brand off aftermarket for my 850, I think the bushing they mention are in the lower fork leg, found no issue with mine, and left them as was, do you have a workshop manual ? because you need to make a tool to be able to separate the stanshon from the fork leg, basically I used a length of tube around 15mm OD with a 17 or 19mm ( I can't remember which) bolt sat in the end of the tube, I drilled both the tube and bolt, and used a split pin to keep in place.
Basically you're making a very long alen key, from memory the Haynes manual gives you an idea how to make one.

[bwringer]

Here in the metrically retarded US of A, you have to make a fork damper rod tool by using 1/2" all-thread with nuts that are 3/4" across.

Fortunately, it happens that 3/4 inch is almost exactly 19mm.

There are also heavy duty 1/2" thread nuts that are larger than 19mm across, so make sure you get the right ones.

I'm pretty sure the procedure is documented in detail in the manuals on Basscliff's site.


Unless the forks have been somehow damaged or run dry, GS fork bushings (they have various names on the fiches, and often aren't even listed) are usually in fine shape -- there's normally no need to replace them until the bike accumulates 80,000 to 100,000 miles or more.

[mmattockx]

I have looked on the Z1 website and found the seals and new dust covers are available. However - I spoke to a service manager at a local dealer about it and he said that I will need the "bushings" also ? An upper and lower bushing..?

The bushings are two (usually two, some older/more economical fork designs only have one) rings that separate the upper fork leg and the lower and act as bearings to allow the upper and lower pieces to telescope without wearing against each other. Assuming there has always been oil in your forks the bushings last almost forever. The chances you will have to replace them are extremely low. That said, the bushings don't cost much and if you want to change them for peace of mine while you have the forks apart that is reasonable.

Looking at Partzilla, the fork diagram shows only one bushing:



It is #21, shown at the bottom of the upper fork leg. It is a split ring and slides onto the end of the upper leg and sits in the groove you can see there. If there was a second bushing it would sit in the top of the lower fork leg, under the seal (#5) and snap ring (#6).

Your service manual (you DO have a manual, right?) will show you how to disassemble the forks. You will want to make a tool as bwringer describes to hold the top of the damper rod while you unscrew the bolt in the bottom but everything else is pretty straightforward wrenching work. The only other thing is that it helps to have an impact wrench to undo those bottom bolts, they can sometimes be stubborn.


Mark

[Steve]

Here is the tool:





I don't remember the exact cost, but I seem to remember about $6 or $7 at Lowe's.

.

[eil]

I heard a rumor that you can sometimes get away with a broom handle or whittled wooden dowel to avoid making the special tool. Once you get the allen head bolt in the bottom broken free, there's not much resistance to work against.

[mmattockx]

I heard a rumor that you can sometimes get away with a broom handle or whittled wooden dowel to avoid making the special tool.

I have got forks apart by doing nothing but keeping the fork caps on and letting spring tension provide some resistance on the damper rod and using an impact wrench on the bottom cap screw. It doesn't always work, though. Sometimes you need to hold the damper rod even with an impact on the bottom.


Mark

[Wingsconsin]

Great Information - Thanks everyone so far !

Here is the tool:

(Pictures removed)

I don't remember the exact cost, but I seem to remember about $6 or $7 at Lowe's.

.

Is this the 1/2" all thread with 3/4" nuts version of the tool..?

I am going to check my local hardware store - they have a vast selection of Metric - IF they have the metric all thread I am going that way...but if not...1/2" with 3/4" nuts will work just fine too...

Am I reading the response properly that it is likely I will only be changing the seals, dust covers and oil and not the bushings as these are usually just fine....

My bike has less than 35,000 miles on it - so I think these may be okay. I think my excess weight and a lack of maintenance from the previous owners had lead to this failure.

I am strongly considering going with Sonic or Progressive springs as well... I like my Progressives on the Goldwing ..but the Sonic springs are a bit cheaper ...

Any opinions on that ..?

[Chris G]

And here's my tool

[bwringer]

If you weigh more than about 170 pounds (12 stone for our British friend...) you'll be happier with the Sonic springs in the correct rate for your weight and your bike's weight. There's a calculator on their web site.

Progressive brand springs are a vast improvement over the hopelessly limp stock springs, but they're a "one size fits all" solution that only works well for "average" riders.

[mmattockx]

Is this the 1/2" all thread with 3/4" nuts version of the tool..?

I am going to check my local hardware store - they have a vast selection of Metric - IF they have the metric all thread I am going that way...but if not...1/2" with 3/4" nuts will work just fine too...

The 3/4" nut fits well into the 19mm recess on top of the damper rod, there really is no reason to go metric instead. As long as you get a 19mm nut for your metric all thread it will work as well.

If you weigh more than about 170 pounds (12 stone for our British friend...) you'll be happier with the Sonic springs in the correct rate for your weight and your bike's weight. There's a calculator on their web site.

Progressive brand springs are a vast improvement over the hopelessly limp stock springs, but they're a "one size fits all" solution that only works well for "average" riders.

+1 to all. Progressives are OK but straight rate springs of the correct rate are the best option available.


Mark

[Wingsconsin]

If you weigh more than about 170 pounds (12 stone for our British friend...) you'll be happier with the Sonic springs in the correct rate for your weight and your bike's weight. There's a calculator on their web site.

Progressive brand springs are a vast improvement over the hopelessly limp stock springs, but they're a "one size fits all" solution that only works well for "average" riders.

I weigh nearly 170 lbs on the Right side (one leg) alone....

I don't know about stone weight....

I think Sonic is the way to go.. I have done the math and will be at the top rate they have...

If so... what weight fork oil should I consider using...? 15 ? 20?

[bwringer]

I weigh nearly 170 lbs on the Right side (one leg) alone....

I don't know about stone weight....

I think Sonic is the way to go.. I have done the math and will be at the top rate they have...

If so... what weight fork oil should I consider using...? 15 ? 20?

I am an enormous yet high-velocity galoot. After installing proper Sonic springs (I rode for years with a set of Progressives preloaded to the moon), I was able to go from 20W or 30W fork oil to 10W.

In other words, once you have springs that are actually doing their job, you don't need heavy fork oil to keep from kaboinging all over the place.

Try 10W fork oil with the Sonic springs. Cut spacers about level with the top of the fork tubes so you end up with about 3/4" (19mm) of preload. Enjoy.

[Wingsconsin]

Learning to do Fork Seals soon...

Ordered the Sonic Springs today...
1.1 rate according to the spring rate finder.
This should be interesting...