GSX1400 Owners .org

Technically Speaking => Suspension => Topic started by: seth on Tuesday, 31 January 2017, 07:03 PM

Title: Rear Shock Fix
Post by: seth on Tuesday, 31 January 2017, 07:03 PM
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
Title: Re: rear shock fix
Post by: seth on Tuesday, 31 January 2017, 07:06 PM
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


Title: Re: rear shock fix
Post by: seth on Tuesday, 31 January 2017, 07:12 PM
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
Title: Re: rear shock fix
Post by: Blubber on Tuesday, 31 January 2017, 11:15 PM
Title: Re: rear shock fix handy tool
Post by: Mrg on Wednesday, 01 February 2017, 08:15 PM
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  :onya:
Title: Re: rear shock fix
Post by: seth on Wednesday, 01 February 2017, 08:24 PM
Fantastic great share  :notworthy:
Title: Re: rear shock fix
Post by: ARH on Wednesday, 01 February 2017, 09:02 PM
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.
Title: Re: rear shock fix
Post by: Mrg on Wednesday, 01 February 2017, 10:27 PM
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  :onya:
Title: Re: rear shock fix
Post by: gsxbarmy on Friday, 03 February 2017, 08:39 AM
Now written up as instructions which can be downloaded - Go To Downloads / General - "How to fix a leaking rear shock"


Title: Re: Rear Shock Fix
Post by: V_i_c_i on Thursday, 09 February 2017, 08:47 AM
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.  :onya:
Title: Re: Rear Shock Fix
Post by: joejoe on Wednesday, 22 February 2017, 11:23 PM
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! 
Title: Re: Rear Shock Fix
Post by: mlivkovich on Sunday, 21 January 2018, 12:21 AM
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 :imrgreen:

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. :cheers:
Title: Re: rear shock fix handy tool
Post by: Speedy1959 on Thursday, 22 August 2019, 05:21 PM
Quote from: Mrg on Wednesday, 01 February  2017, 08:15 PM
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  :onya:

MRG could you be a little more generous with the size of your photos please..
I left my microscope at work !!
Title: Re: Rear Shock Fix
Post by: lawrie on Friday, 23 August 2019, 04:35 AM
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. ;)
Title: Re: Rear Shock Fix
Post by: Snapey on Friday, 23 August 2019, 06:30 AM
Ingenious Lawrie ... certainly beats the thing I made which will now be binned & replaced today by a copy of your tool.
Title: Re: Rear Shock Fix
Post by: seth on Friday, 23 August 2019, 06:42 AM
I've seen something very simular but you use a rachet strap through the spring and around the jack so when you load up the jack the spring tightens .
A great find on this link/video though  :onya:
Title: Re: Rear Shock Fix
Post by: oldskool on Tuesday, 08 October 2019, 06:14 PM
How much oil do you put in?
Title: Re: Rear Shock Fix
Post by: Speedy1959 on Tuesday, 08 October 2019, 10:19 PM
I used a syringe complete with a needle.
I totally drained all the original oil and then kept injecting EP80 (in my case) into it. I worked the pre load adjuster fully in and out till bubbles stopped.
Then gradually filled it to the brim with the adjuster in the fully out position.
Mine wasn't leaking but I thought I would have a play.
Obviously I did this with the springs removed.
S.
Title: Re: Rear Shock Fix
Post by: grog on Wednesday, 09 October 2019, 07:11 PM
Think i did mine with springs on, cant remember, been a while. Has never leaked again. 90 gear oil from memory.
Title: Re: Rear Shock Fix
Post by: Mister Fishfinger on Wednesday, 09 October 2019, 07:14 PM
What Grog said. Did mine with springs on, also used EP80/90 gear oil, no problem.
Title: Re: Rear Shock Fix
Post by: Eric GSX1400K3 on Friday, 31 January 2020, 09:51 AM
Dear Brains trust,

About to rebuild the rear shocks on my K2 after noticing oil leak around the preload adjusters, and that the left one wont wind down past the third ring.

Bike has 42,000km on it and has original  shocks

This was after the ride with my wife as pillion last weekend, so the extra load has highlighted an age/wear issue (on the bike, not the wife   :lol:)

Reading on here, several different grades of oil are mentioned : 15W40 or 90W gear oil to name a few.

I chatted with another bike mechanic, he uses 10w oil for these type of units.  The front forks run 5W, can i use the same in the rears?

As theyre basically a hydraulically damped piston, a 46vg hydraulic oil may also be suitable.

After ive stripped them i need to see if i can reuse the seals or find a suitable replacement seals.

Any consensus on which oil grade is best, or is the grade / weight not important as long as it has oil in it?

Also, im assuming  the nitrogen side of the system is not serviceable? I.e. the remote resevoir hanging off the back.
Title: Re: Rear Shock Fix
Post by: grog on Friday, 31 January 2020, 05:44 PM
Eric, i used gear oil in adjuster only. I can rem. reading not fork oil in shockies, must be shockie oil. Sorry, all i know. Shop did mine for $400. I find them good.
Title: Re: Rear Shock Fix
Post by: Eric GSX1400K3 on Friday, 31 January 2020, 07:04 PM
Thanks, I'll go with 90w gear oil, if ita good enough for the chain.... :lol:
Title: Re: Rear Shock Fix
Post by: grog on Friday, 31 January 2020, 07:31 PM
Mate, after shocks rebuilt, only use 3 rings for me, maybe 4 if loaded 2 up. Much more compliant, just seems to work. Standard springs. Had forks done also, Wilbers springs and set by shop for weight etc. Can really feel front and back talking to each other.
Title: Re: Rear Shock Fix
Post by: Eric GSX1400K3 on Tuesday, 04 February 2020, 12:18 PM
So rebuilt one on the weekend.  Preload was full of junk, bump stop removed as this was perished.  Refilled preload adjuster with about 5 to 10ml of 80w90 gear oil after a good clean out, reused o rings.

Gas shock and nirltrogen cartridge cleaned up using 2000grit wet and dry paper and wd40.

Used car spring compressors, bit fiddly but worked ok, some scratches on the  spring coils unfortunately.

Preload adjuster now runs from 0 to 5 rings easily. Left it at full 5 ring preload overnight when rebuilt , no leakes so all good.

Will do the second one this week and refit on the bike over the weekend.

I did notice the K2 setup only has 2 o rings, no additional seal at all. Dirt and grit collects in the top ans works its way down into the adjuster.  Oil that came out was pretty dirty, i flushed it out with degreaser and compressed air, then with oil before a refill using  the syringe method. Worked well.
Title: Re: Rear Shock Fix
Post by: Andre on Tuesday, 04 February 2020, 01:02 PM
Quote from: Eric GSX1400K3 on Tuesday, 04 February  2020, 12:18 PM
I did notice the K2 setup only has 2 o rings, no additional seal at all. Dirt and grit collects in the top ans works its way down into the adjuster.  Oil that came out was pretty dirty, i flushed it out with degreaser and compressed air, then with oil before a refill using  the syringe method. Worked well.

Just read up on this today on a German forum. There are 3 different shocks. The first (K2-K?) only had what you saw (no dust seal) The second has a white seal. That was an unsuccessful remedy to the problem. The third (black seal) was a somewhat successful fix.

A guy who has done many of these advised against adding a seal to the K2 shock. He recommends blowing with low pressure air in the space regularly to keep it clean.
Title: Re: Rear Shock Fix
Post by: Eric GSX1400K3 on Tuesday, 04 February 2020, 01:22 PM
Yep, quality bit of kit. 1 o ring is retained in the fixed body of the adjuster, the other in the "piston" or movable side, neat set up.  The gap between the two is small, less than 1mm i guess, but fine dirt still gets in.  Note, the amount of oil filled in determines the number of rings you can click to.  Less oil means less rings.

I did not even try to add an extra seal, just no room and not needed, cleaned and re used the existing  o rings.
Title: Re: Rear Shock Fix
Post by: Andre on Tuesday, 04 February 2020, 01:41 PM
Suzuki could have saved themselves a bundel of $ and us a lot of grief by using the common mechanical preload adjuster.
Title: Re: Rear Shock Fix
Post by: seth on Tuesday, 04 February 2020, 05:58 PM
Someone years ago made a replacement adjuster with 2 locking rings like the much more common rear shock adjusters fitted to other bikes and makes .
They offered to do a batch but got no support back then .
If someone could get them machined now I'm sure they'd sell well .
Title: Re: Rear Shock Fix
Post by: grog on Tuesday, 04 February 2020, 06:32 PM
I remember that Seth. Was a great idea. Think from memory, he posted all the dimensions etc. Wasnt expensive except post to Oz. Lost on old org.
Title: Re: Rear Shock Fix
Post by: seth on Tuesday, 04 February 2020, 08:43 PM
Yes it was lost
The adjusting rings were from China cheap enough .
Just getting the machining done cheap enough I think I can come up with the sizes with a bit of research.
:cheers:
Title: Re: Rear Shock Fix
Post by: mlivkovich on Tuesday, 04 February 2020, 09:25 PM
I ordered preload nuts (m50x1.5) and my plan is to machine collars to make trouble-free preload adjusters. If this works, I will post here exact measurements and pics!  :cheers:
Title: Re: Rear Shock Fix
Post by: seth on Wednesday, 05 February 2020, 05:15 AM
@mlivkovich do you not fancy making a few sets ?
Title: Re: Rear Shock Fix
Post by: mlivkovich on Wednesday, 05 February 2020, 07:30 AM
Quote from: seth on Wednesday, 05 February  2020, 05:15 AM
@mlivkovich do you not fancy making a few sets ?

I will first try to make useable adjusters and try it on my bike. I weight too much (130kg) and I need more preload or stiffer springs. First I'll try cheaper solution and fabricate adjusters. If this works, the easiest part is to make couple of them, it's pretty simple... collar and nut(s), simple isn't it? And it can't be expensive! :cheers:
Title: Re: Rear Shock Fix
Post by: VladTepes on Wednesday, 05 February 2020, 05:57 PM
I paid $$ to have a place rebuild my shocks a couple of years ago, and one is leaking again.  :furious:
Title: Re: Rear Shock Fix
Post by: KiwiCol on Wednesday, 05 February 2020, 06:02 PM
I think I remember that being done too.
Title: Re: Rear Shock Fix
Post by: Andre on Wednesday, 05 February 2020, 06:44 PM
Quote from: VladTepes on Wednesday, 05 February  2020, 05:57 PM
I paid $$ to have a place rebuild my shocks a couple of years ago, and one is leaking again.  :furious:

Mine too. I wouldn't blame the guy who repaired it though. The preload adjuster leak is a matter of bad design. I have Model 2 (with the white ring). After noticing that it leaks again, I probed with a tooth pick a little and there was a lot of dirt in there. Wouldn't have noticed the leak if I didn't play with preload to see if it was still tight. Shows that without much pressure in the system the dirt did its evil job. Guy in German forum who has repaired many adjusters says that there is no guaranty that they will not leak again. His best advice is to keep it clean. The amount of dirt in mine surprised me as I only ride in dry weather.

Overall I am happy with the rebuild. Shocks still work great. Internally setup for me was well done. Preload adjuster is set to zero so I am not affected by the leak since I only ride solo without luggage. Gaining another 10kg I would need the preload adjuster though :facepalm:

Shocks are still good for the coming season. Next winter I'll get new ones. Originals will be kept as a backup as the new shocks will go in for rebuilds regularly (by the manufacturer - Wilbers).
Title: Re: Rear Shock Fix
Post by: VladTepes on Thursday, 06 February 2020, 10:05 AM
Why would the new ones need to go in for regular rebuilds?
Title: Re: Rear Shock Fix
Post by: mlivkovich on Thursday, 06 February 2020, 02:16 PM
Quote from: VladTepes on Wednesday, 05 February  2020, 05:57 PM
I paid $$ to have a place rebuild my shocks a couple of years ago, and one is leaking again.  :furious:
I've done this by myself two times in two years, put new seals and polished adjuster parts (area where seals sit) to prevent leaking and it still leaks after few tkms. Preload always set on max and dust just make them leak.
Title: Re: Rear Shock Fix
Post by: Andre on Thursday, 06 February 2020, 10:05 PM
Quote from: VladTepes on Thursday, 06 February  2020, 10:05 AM
Why would the new ones need to go in for regular rebuilds?

I could have said service instead of rebuild. Since parts get changed by service and it can turn out to be a bit more, I called it a rebuild.

Shocks are mechanical devices and have to go through a lot of work (some more than others). How often oil, nitrogen, piston seal, rubber buffer, and seal block (done with service) should be changed depends on usage. I have mine done at around 20000 km. The fork I do myself at 10 - 12k (oil, seals, more if needed).

Title: Re: Rear Shock Fix
Post by: Eric GSX1400K3 on Monday, 10 February 2020, 08:10 PM
 :notworthy:so completed the rebuild on Sat. Left both on max preload for a few hours to check for leaks, none observed. Was able  to go through full range of preload, adjusted oil level to go just past no.5 ring.  Up and down a few times, then refitted to the shock assy.  I also compressed the cylinder rod a few times on each of the compression settings, no leaks from the cylinder seal, and you can feel the difference each of the  4 clicks of the compression damping has,or i could, it seemed to take a bit more effort and time to fully compress.  Refitted to the bike, checked allsettings were the same borh sides, put it on 2.5 rings preload, 2 for rebound and compression respectively, then went for a ride.  No leaks and i was able to feel the suspendion working a bit more, i suspect with all the dirt in the preload adjuster, that it was not the same left to right.  Will try to go a bit higher on preload and see what that does.  Good result all round  another job done.