Leaking Fork Seals <3000km

[jake]

Hi all,

I have had a suzukig gs250t for about a year now and I am prepping for its annual service post exams. When I got the bike I serviced everything, and it has all been going well, bar for some mysterious hiccups with the carburettor that have self-resolved, alongside a new voltage regulator/rectifier.

I noticed yesterday after a short ride that there was a significant amount of oil leaking from the left hand fork, enough to have half the engine covered in dirty oil and to be dripping down the dust seal. I've only put on just under 3000km and I'm not a particularly aggressive rider. I serviced and replaced the seals in both fork legs, which were in terrible condition when I bought the bike, bottomed out, and filled with grunge.

There was a small bit of a leak before, but with the forks being 40 years old, I wasn't too alarmed. There were striations on the inner fork. The leak is suddenly far worse now and I am worried about the fork bottoming out. I was going to use the bike to work as a courier through the lockdown after exams but this has thrown a bit of a spanner into the works.

I will be able to get the forks etc.. apart by the middle of may, but I wanted to ask what you guys had to say on the matter and if you knew of any quick fixes to keep the bike on the road until I can check the seals. You guys have experience working with older bikes and I'd appreciate your advice.

Thank you in advance.

Jake.

 

[Rich82GS750TZ]

see this current thread. Worth a shot.
https://www.thegsresources.com/_for...he-bike-with-oil-sweating-from-one-front-fork

 

[jake]

Thanks Rich, will check it out.

Had to take an emergency trip out to the dentist just there, the oil is leaking all the way down the fork now ...

 

[jake]

given that there were striations and that the suspension was in bad nick when I bought the bike, does anyone have any tips in case the inner tube is worn to bits. I.e.doesnt seal due to being very worn? is there a paste that can be applied at each seal replacement to help or something? When I checked it last it was pretty bad, not the worst, but quite bad.

 

[salty_monk]

You can fill the small pits with epoxy after a good cleaning with carb cleaner or solvent.... then sand back smooth. Essentially the sharp edges of the pits catch & tear the rubber of the seal....

 

[oldGSfan]

I buffed my forks with my grinder setup, a mop with white rouge. I was surprised how many little visible imperfections came out. Heard that super glue works too on the pits but all I've ever glued with that stuff is my fingers.

 

[jake]

These sound like great ideas, I'll have the forks apart soon and I'll see what the damage is.

Thanks.

 

[Gorminrider]

just as an added thought, if you have any heavy machinery places about, they might advise. Hydraulic rams have a lot of the same issues ( front-end loaders, farm equipment, bulldozers...) Even your local farmer will likely know something.

Or...you might find replacements on ebay etc. This worked for me versus repair.

 

[jake]

Thats some fantastic advice, my family used to operate lots of drilling equipment, seals would go all the time. My first thought is to check for dings and scratches, do a bit of a polish and then cut/tighten the spring around the seal if it hasn't torn. If that doesnt end up working I will bring it around to a seal maker and ask them about it, as is often the case in Ireland they may just want me to replace the entire thing. I'll give the epoxy/superglue idea a go then. I will be pulling the fork off tomorrow if theres no threat of rain. I am not placed right now for a replacement for anything barely even fork seals, this covid thing has me even more smashed than I normally am haha.

I'll let you know whats up asap.

Thanks.

 

[jake]

I pulled the dust seal and probed with a feeler gauge in case there was any dirt, the oil had built up a little bit and was milky pink, which is indicative of water right... wiped it down with blue roll and took the bike for a 15 min spin with the dust seal off, extending and compressing the forks periodically. Stopped twice throughout to check for streaks and leaks etc... didnt really see anything significant though, but the milky oil tells me something isnt right. I shouldnt need to change fork oil that frequently... I will take it out for an hour tomorrow in some bumpy spots to check again before pulling. If the leak has stopped then I dont want to disturb the seal and would rather just change out the oil. Let me know what you think.

Thanks

 

[Gorminrider]

milky by itself whatever colour IS probably water. If the Fairies came by and fixed it in the night, maybe they peed in there too.

The Pinkish" sounds like Automatic Transmission Fluid was used as fork oil, which is perfectly ok. Some Suzuki bikes call for a mix of motor oil and atf. (I think yours might) so fork oil changes are very economical.

 

[jake]

Yeah I thought so, didnt want to come across as cocky haha. I pulled the fork off the bike and drained the milky mess, went to pull the damper rod but I cannot get enough friction for the life of me, its on quite tightly and I did use some light threadlock when I serviced it last as recommended by a friend. Unfortunatley I am by myself this time and I only have the allen key, my body and the bike to remove the darn thing, but it just keeps slipping. Does anyone have any recommendations on how to remove it? I dont have a vice or anything.

Thanks.

 

[Rich82GS750TZ]

You can make something like this from a broom handle and shove it down into the top of the damper rod. Hold it steady with one hand and work the Allen key with the other.

 

[jake]

Many thanks Rich, was able to use a makeshift rod to do similarly, got it off nice and easily.

Attached is a photo of the stanchion, it unfortunatly has some dings as shown in the photo, the rest of the rod is in very good nick, it must have been the other one which had more severe striations.

https://imgur.com/a/kgAksCs

I am uncertain how to approach these as I am aware that the chrome on these rods is very, very thin, and I don't have the money or equipment to buff or rechrome. I might be able to get a mechanic to buff these out, what are the chances these have been rechromed?

thanks.

 

[Grimly]

You can dress those pits up with some 1000 grade emery paper. Just enough to blend the edges in and buy some more time - possibly years if you do it right.

 

[Gorminrider]

they don't look like much to me!-I've polished off much worse and gotten away with it. Try to be sure that the marks you see are indeed responsible for leakage. It's pretty easy to b*gger the seals putting them in but...if those scratches have sharp edges , for sure I'd take the edges off

...I use a sharpening stone. a Fine one. In lieu of that wrapping a stiff narrow flat stick with fine grit wetndry paper works too...

Reason is...to sand a round object, always use a flat surface...this will limit the area you are "attacking". If you get through the chrome, it's brass under it. Not to worry, it works as well UNLESS you have gotten so far as to deviate much from round.

 

[jake]

This news is a relief to me. Thanks for the sound advice, I dont have a proper whetstone or other sharpener, so I'll make use of a feeler gauge or something similarly stiff with fine grit paper like that. I'll get stuck in tomorrow, put it all back together and see what the craic is, I know I'll need to replace the seal, but I might get away with it until new ones arrive. I do have some extremely fine sandpaper which I can use to finish in case these are not responsible for the leak, they are the only marks I can identify. I can also use a microfibre cloth and some aluminium polish.

I'll forward on photos too.

I really appreciate the help with this, thankyou.