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premature shock seal failures. root cause(s) ?


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Hi All. I was wondering if anyone had any ideas as to why my aftermarket shock seals are failing (imho) prematurely? Just sent back to manufacturer's service center to be fixed. I suspect they will change the seals and refill but this is the second failure, both at low milage imho. Maybe issue could be fixed more permanently if i knew what to ask for. Would like to avoid re-occurrence. Ideas?


some info:

June 2009: 82300 Km; new. 1700$ ouch. a well know brand, starts with H.

July 2010: 99100 Km: both leaked: (10 k miles) sent back under warrenty

oct 2014: 134000 km: (22 k miles) smelt burning oil on muffler in retrospect likely shock leaking

may 2015; confirmed both leaking


since then; rode bike minimum due to shock - pretty dangerous and unenjoyable, likely stressful on other parts of the bike too .rode despite the shock to avoid issues w. long term lack of use; now at 140000 km.


i think these failures are not just random bad luck (10 k miles, then 22k miles only) - i suspect design or manufacturing issues.

any thoughts?


note i requested they be configured (built) for 2 up with heavy me (200 lb), light wife (110), and trailer (tongue guestime say 40lb) - i wonder if the springs are too strong and the things are exploding from the inside ?


i usually park on the center stand as it takes less space. maybe i should use the side stand so there some weight?


Also i dont actually know if it is the seals that failed, but there is no damping, and there is an oil mess. i would assume seals.


i know two years have passed, wish i caught it under warranty, but I got two young kids so time to work on stuff is a challenge and have to prioritize, or procrastinate as teh case may be; this job got put off as is a time hog;

On a scale of 1 to 10 ranks about a 7 in the pita factor to get the repaired - about 3 days:

(a/ tupperware off, b/ rear wheel off, c/ seat off, d/ seat ajuster off, e/ shock out, f/ old shock in, g/ rear wheel back on , h/ then pull the front shock, i/ then box it and drive to the USA (4 hour round trip) to avoid huge shipping fees and custom and brokerage shenanigans.. j/ Wait for fix, k/ pay for fix, L/ pay for shipping back and repeat in reverse order more or less. Bike out of commission due to the leak and during repair. Garage full of disassembled bike, Tupperware, etc.



Edited by Unhofliche_Gesundheit
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Afternoon Cameron


Without seeing / handling the shocks it is about anybody's guess.


The usual cause of leaking shock seals is a bent shock shaft, or crud build up on the shock shafts, or nicks on the shock shafts, or dried out seals, or seals nicked during assembly, or inferior parts, or ?????


I have seen fork seals leak due to washing bike with very hard water then storing the bike. The hard water leaves abrasive calcium deposits on the fork tubes. Then when the bike is next ridden those calcium spots abrade the seals.

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thanks DR, well so that is interesting, sounds like you would suspect where the seal interfaces with the shaft. the shaft looked pretty good - new in fact but i did not think to examine closely and now the shock are away. the shafts looked very clean with no crud, not what you would expect if they had been leaking. there was lots of crud on the painted surface and on the bike. i have no idea how much sag there is or should be or how much travel there is / how close i come to bottoming out (stuff i will be looking into) ; maybe they did get swept clean over time. they dont move when i put my weight on them , cant pump them up and down like a 125 dirt bike or a mountain bike.


So you got me thinking it would be nice to see exactly where the leak was - which to my mind was not obviously on the shaft. Unfortunately the hocks are hard to view when on the RT as you know - the tupperware is great for extending the riding season but a trade off for working and inspecting the bike. I will have to add more frequent inspections (more often than once every 6 years :dopeslap: so if they leak again i can catch them in the act.


when they were fixed last time i did not get a report of what happened but was under warrenty, this time i will press for more answers. Happy Monday/Happy Halloween.

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Hi Kent, I think yes is an exception, i feel i am not getting good value - don't think i was being cheap; 360 US$ for the front.

590 US$ for the rear, plus 270$ for rear remote preload adjuster. so that is 1427$; plus shipping, installation not included. June 2009 dollars, worth a bit more back then. A bit less than some competitors. I had to work around some scheduling issues which was the main deciding factor. But c'mon compare the 360$ to a front shock for my benz - top stuff is 120$. for 3 times the price i dont expect 20% of the life, arguable the benz shock has to work a lot harder: I will say based on my windscreen and these shocks, and on buying plenty of car parts over the year, it is best practice, if you are keeping the machine, to buy the best quality, even if is significantly more. If these blow up again in another 20,000 miles i am going to go out of my way to share some bad press. for now aftermarket starting with H is all I am saying. ( see above , quoting myself; "1700$ ouch. a well know brand, starts with H") 1700 cdn $ at the exchange rate of the time.


Edited by Unhofliche_Gesundheit
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