Rear Shock Fix

[seth]

copied from the old org

Left rear shock on my K3 popped last Friday after 20K kms, gracefully spraying its content on top of my new BT 020....

Called my dealer, who called the Zook agent in Sweden, who talked to Nihon, and they refused to replace the faulty shock because it´s not cowered by the 5 year engine warranty!!! nor the 2 year parts warranty.

At that very moment I got the feeling I was smoked, f---ed, you name it. Two hours and a couple of beers later, the situation was analysed and I realised I had to solve the problem on my own:

Here´s my fix:

1. removed the faulty shock

2. clean it from dirt and fluid/oil

3. on the inner/wheel side of the shock, on the back of the main spring pre-tension chamber, there is a tiny M5x10 mm drain plug with a copper washer - remove it after the black pre tension knob has been completely released (there should be a noticable slack when relased to its en position).

4. jog the pre tension knob back and forth until the chamber with fluid is completely emty, tilt the shock if necessary to empty remaing fluid, then return knob to its end none-pressurized position.

5. place the shock horisontal with the M5 drain hole at the highest point.

6. fill the chamber completely with 15-40 engine oil (CAT is using engine oil in all their hydraulic systems, and it works perfect, and the spring pre-tension reservoir is NOT connected to the main pressurized system, its just a hydraulic isolated substitute for a mechanical device.

7. replace the the drain plug with a new M5x10 mm Hex bolt and a new copper washer, tighten the plug and start turn the Pre-tension knob in tension direction untill the spring starts to compress.

8. compress as much as possible, then retract and upen up the reservoire and refill again. It took me three runs to completely fill the reservoire. The last time I could easily press the main spring down the fift marking, by using the knob.

9. leave the shock under pressure, pref. tightened to mark 3-4 over the night.

10. if no leaks and if the shock is maintaining the same pressure in the morning, attach it to bike and prepare for a test blast.

11. check both shocks for same settings for all adjustments.

12. go for a day trip with at least spring pre-tension on marking 3 - if no leaks, the cure worked, and you don´t need to go into further useless discussions with Zook nor your dealer.

13. if not working, go for a pair of Hagon Nitro´s

General disclaimer:
Never work on pressurized systems, always read an follow instructions in the GSX 1400 manual. This worked for me, but I´m not in the position to authorize or recommend anyone to follow my advice on how to solve the GSX 1400 shock problems.

Fred

i think folk now use different oil as get better results than just engine oil
I'm sure barmy has the spec of it

seth

[seth]

more info from old thread

Shock fix - theory behind.


My approach to the problems with the GSX 1400 rear shocks is slightly different to the one expressed by the mainstream of forum postings. In my opinion the

shock is actually a quite nice piece of engineering and what went wrong was the the process of factory settings > shipping > end user instructions.

1.
The shock is designed with a hydraulic main spring pre-load adjusting function - that is a pressurized chamber, also used as the reservoir for the hydraulic

fluid. There are at least 3 separate sets of sealings used to seal off and contain the pressurized fluid to the chamber: bottom, top and the knob-piston

sealing.

2.
I simply don´t believe that Zook engineers cannot design and dimension an o-ring/sealing seat and select the appropriate setup of o-rings/sealings - they

invented dry, tight and bullet-proof engines and stoled the show from Little England - we have a weak case for such an assumption.

3.
The pre-load adjustment is a low-pressure system. In some instances the pressure in the system is so low so that enought pressure is not being built up

behind the two main sealings so they simply don´t close in and expand in there seats - that is by (my) definition the startup of the entire leakage process.

4.
If the bike goes shipped with its shock pre-load adjust knobs adjusted to relieve the main spring from pre-loads tension or if pre-set only eg 1,5 rings,

because of factory setting routines, sealings won´t settle and will have little chance to deal with the extreme dynamic forces the shock absorber system

eventually will face in use under (sometimes bumpy) road conditions, and are likely to eventually give up - because of fluid leakage, and because of

sealings not fully closed and expanded in their seats.

5.
Zook could have avoided this by admitting to them selves and their shipping people that all OEM Showa shock units should have been put on at least third

ring pre-load immediately after chambers being filled-up. That would have saved us from this pain, which has dragged the otherwice nice 14 down in the mud.

I have seen K2s stored at retailer´s with slacked pre-load settings until late 2004 and then eventually being sold on campaign pricing. These bikes are dead

set to have problems, one doesn´t need to be Einstein to realize that.


6.
Test report on the Fix:

- repaired shock still completely dry and tirght,

- keeps its setting (currently fourth ring),

- 300 KMs in the first test blast, working real nice.


7.
We need a few more cases in order to build up some reliable statistics underpinning the relevance of the fix.


8.
The reservior chamber plug is an M5 hex with a blocking pin in center of the wrench hole. I knocked off the pin in order to reach down with a Hex wrench.

Took a while but finally succeeded.

9.
Dust and dirt could have played a role as well as a burst or rupture of the sealing, but it´s not very likely given the successful test results this far.


10.
I´d like to bring in the legal aspect on this. Can you imagine the situation in the US were people are filing lawsuits and raising claims for nothing? If

GSX 1400 had been sold in the US, given the 14s preference for popping shocks while in the midst of a nice blast, there is a high likelyhood that the

situation would have been different, that´s for sure! That could be part of the reasons, why 14 has not been introduced to the US, and never will before

going discontinued nech year (another reason is of course Pollution and Environmental legislation in states like California, but thats another story)

11.
I´ll monitor the fixed shock and post regular updates on the forum.


Fred


Disclaimer:
Never work on pressurised systems. Read and obey warning labels on the shock. Follow instructions in the GSX 1400 Manual. Always consult your authorized

dealer when facing problems with your bike. The above and all preceeding statements and views from my side regarding the GSX 1400 shock case should be

considered my views and are not representative for anyone else. I am not authorized to issue any recommendations on how to solve GSX 1400 shock problems,

and I strongly discourage anyone to follow in my steps.I take no responsibility for any action(s) undertaken by anyone referring to statements or views

hope this is helpful
seth

[seth]

alternatively oil to refill the hydraulic adjusters with copied from.old firum ftom gsxbarmy's post.



Many refill with Hypoy EP90 oil (which is a bit thicker than the standard stuff) which seems not to leak again in the majority of cases - shock works just as well when filled with this as well

[Blubber]

[Mrg]

thought I would show you this little tool, helps  to remove the rear shock springs. very simple, took just half hour to make. two pieces of 25mm plywood, two threaded bars and a couple of holes.  to remove the springs to clean and free the adjusters. also to help  paint the springs without scratching them.  this tool is  effortless.

just tighten the bolts on the threaded bar evenly, when the spring is compressed enough and the shock protrudes through the 55mm hole, there is a coller type washer which will be lose, remove it and slacken the bolts on the threaded bar evenly again, job done. cheers.

I took this from our sister site for information for other user's

I think this is a very simple tool to help you do your own rear springs and paint ,spray or service 

[seth]

Fantastic great share 

[ARH]

Excellent!  I did the adjuster repair on my K2.  Had the same issue, set at 1 when I got and handled like a pig in a blanket!  Now sitting at 3.5 for the last 3 years with no issues.

[Mrg]

yea I know I took mine off last year and had a right fight with it , so this is my next build so I can do them at ease this year 

[gsxbarmy]

Now written up as instructions which can be downloaded - Go To Downloads / General - "How to fix a leaking rear shock"

[V_i_c_i]

My spring remover...

http://v-i-c-i.rajce.idnes.cz/GSX1400.ORG_Photos/#201601.jpg

On that type is not any danger scratch spring paint. 

[joejoe]

Just repaired mine successfully (for now).  For info I replaced the o-rings in the main chamber of each unit.  The sizes for the o-rings are 46 * 2.5mm(dia).  I used nitrile o rings and lube oil from heavy machines at work (gloopiest I could find).  Now got 5 rings and they seem to be holding up ok. I used a syringe (full of oil) through the drain hole to separate the 2 halves of the unit which worked well.  Now the shocks have been sent away to fix the rear compression damping adjustment and get refurbished.  Hopefully better than new! 

[mlivkovich]

Repaired preload adjusters today because left started to leak. Reused old seals and added few coats of teflon tape under seal on inner part of adjuster (one with 5 rings) to make it more tight fit. Got rid if old cracked plastic cleaners  and replaced them with silicone seals which I streched over  to make them fit. I cleaned everything (full of dirt which caused leakage) and put grease under silicone seals to prevent dust to enter, colour is not the prettiest to see but they do the job. No leak for now

One tip: It is much easier to refill them with oil before assembly. Put adjusters (with seals) together and set to soft while knob is on hard position. Then use syrige to add oil. While adding oil press them by hands to hard position to create vaccum (takes time but it works). Then turn knob to soft to create more vacuum while adding oil. Repeat few times from soft to hard position and add oil if nedeed. Now, set to soft position and you are ready to install them to its place.

[Speedy1959]

thought I would show you this little tool, helps  to remove the rear shock springs. very simple, took just half hour to make. two pieces of 25mm plywood, two threaded bars and a couple of holes.  to remove the springs to clean and free the adjusters. also to help  paint the springs without scratching them.  this tool is  effortless.

just tighten the bolts on the threaded bar evenly, when the spring is compressed enough and the shock protrudes through the 55mm hole, there is a coller type washer which will be lose, remove it and slacken the bolts on the threaded bar evenly again, job done. cheers.

I took this from our sister site for information for other user's

I think this is a very simple tool to help you do your own rear springs and paint ,spray or service 

MRG could you be a little more generous with the size of your photos please..
I left my microscope at work !!

[lawrie]

If you have a trolly-jack, you may be able to cobble something similar to this I did many years ago, still use it.

https://www.dropbox.com/s/i9r3ruu9w16g5o7/SpringRemoval.MP4?dl=0

VERY quick & easy.

[Snapey]

Ingenious Lawrie ... certainly beats the thing I made which will now be binned & replaced today by a copy of your tool.