Seeping Fork Seal

Seeping Fork Seal

Postby Samelak » Thu May 24, 2012 2:31 am

Very frustrating that my newly rebuilt 80 CBX fork (one side only) started to leak only after about 300 miles. I even used Honda seals. Is it time for new tubes? I do have some pitting, but it's towards the top. I also just installed a Pazzio fork brace, but I do not think it is related. Any thoughts?
Samelak
ICOA Member
ICOA Member
 
Posts: 171
Joined: Mon Jan 04, 2010 6:04 am
Location: Okinawa, Japan

Re: Seeping Fork Seal

Postby Larry Zimmer » Thu May 24, 2012 10:17 pm

Any pitting on the part of the tube surface that slides through the seal will damage it enough to cause seeping/weeping/leak. If not too deep, it can be polished by hand. Should disassemble the tubes to be certain that the entire length that strokes through the seal gets 'cleaned up'. Depending upon the depth of the pitting, start with a 400 grit wet-or-dry paper lubricating with oil. (Engine oil, fork oil, just don't use brake fluid!!) Work the sand paper AROUND the tube shaft, NOT up-and-down. Polish with the course paper until the pitting is gone. Then, use progressively finer paper up to about a 1500 grit to continue to polish the tubes smoother. If you are able to eliminate the pitting, this polishing will have things working well. I would install new seals, again, just to be 'safe'. Sorry about the need to disassemble, again; but, it's the only certain means of polishing the full stroke in my experience. Good luck.
Larry Zimmer
ICOA Web Post/Pix/Video Archive Mgt
ICOA Web Post/Pix/Video Archive Mgt
 
Posts: 737
Images: 144
Joined: Mon Dec 15, 2003 3:32 pm
Location: Brighton, Mich

Re: Seeping Fork Seal

Postby Jeff Bennetts » Fri May 25, 2012 8:40 am

I saw a post on another MC forum I belong to that mentions a product popular with farmers and people that use equipment with a lot of hydraulics that will fill any pits in the cylinders, I'm tying to find it and I'll post my findings when I locate it.

I know some people have had success with using epoxies.

Resourced from the CB1100F forum.

Here's a pretty good technique and product to repair pitted forks that will last better than the epoxy method and look better too. From "Tourmaster" (Bob) at the Custom site. Reposted here with his permission. I really like the Cigar lighter idea for a torch, great idea. I think some smallish fine files would also help the process.

Tourmaster wrote:
Okay Gene, here goes ... our local bike shop repair guy (Hugh), who I have a lot of respect for, was very forthcoming concerning his "Pitted Fork" repair weapon of choice. Hugh has in the past used the epoxy trick, but later found that the farm and heavy duty equipment guys were repairing their pitted hydraulic cylinders with something a little more robust ... and just as easy to apply. Since using this simple product(s) over the past several years, he has had no returns from his many customers.

I took some, rather crappy, photos of this stuff at his shop this morning. It's actually a solder/braze like product that is simply melted into the offending pit area. Here's the photo of the container that holds several of the solder like wires.

Product Name: Cronabraze 92C CW1020 Acid Core


And here's the solvent/flux he uses to first prepare the area.

Product Name: Cronasolv Eagle F930


Hugh said that the supply company he gets this stuff from is Lawson Products ... here's the link: http://www.lawsonproducts.com/website/m ... enDocument
NOTE: In the photo showing Hugh's example, he was actually able to get the wire in shorter lengths contained in a smaller tube, rather that a large roll as shown this this catalog shot.

Here's their catalog for the specific items including the solder/braze wire: http://www.lawsonproducts.com/webapp/wc ... GSOLDERING

And next the solvent/flux: http://www.lawsonproducts.com/webapp/wc ... 2CPOLYMERS

I actually had a chance to watch Hugh do the repairs to my GS1100 fork tube, which had one pitted area. Hugh's method of fork tube pit repair generally follows these simple steps:

1) In my case I actually had removed the fork tube allowing him to lay it flat on his work bench
2) First clean off the offending area with a general cleaning solvent to get rid of any oil and debris
3) Using very fine emery (ie; crocus) remove any potential raised burrs, but leave the depression area of the pit as is (ie jagged)
3) Quick flush cleaning of the area again
4) Apply the flux product
5) Preheat the pit area a bit and then using a simple cigarette lighter torch melt a very small amount of the Cronabraze solder/braze wire into the pitted area.
6) Allow the area to cool and then buff the excess solder/braze material away using, again, very fine emery cloth ... buffing to a smooth finish.
7) Reassemble and cruise for many happy years of NON-leaky forks


The cost of refurbishing and rechroming heavy duty equipment hydraulic cylinders have driven machinery companies to find simple and cost effective repairs, that will stand up to the riggers of the construction and mining industries. Since these are certainly more demanding applications than us lightweights cruising around on our 750's ... I like the approach.

Image

Image
User avatar
Jeff Bennetts
Amazing Poster
Amazing Poster
 
Posts: 1341
Images: 83
Joined: Wed Mar 05, 2003 9:38 am
Location: Ohio, USA

Re: Seeping Fork Seal

Postby NobleHops » Fri May 25, 2012 10:53 am

OK, this is freaking AWESOME CONTENT. I totally wish I had a set to try it on. I bet this would work on brake pistons too. I had an otherwise tasty piston with one big pit. Perfect candidate. I think I still have it, if so I'm going to order some of this stuff and try it.

I saw a local auto stereo installer dude with a teeny propane soldering torch, which fit in the palm of his hand. Snapped on with a trigger, full heat instantly, fine flame tip, instant off. That would work perfectly with this. I want one of those! I have no feel for my electric soldering gun...

N.
Nils Menten
Tucson, Arizona, USA

'80 CBX, sort-of restored :-)

http://noblehops.smugmug.com/Motorcycles/The-Not-Restoration-of-My/5334012_jN2Rnx
User avatar
NobleHops
ICOA Member
ICOA Member
 
Posts: 2416
Images: 28
Joined: Mon Jan 25, 2010 8:17 am
Location: Tucson, Arizona, USA

Re: Seeping Fork Seal

Postby kbart1 » Sun Mar 02, 2014 1:54 pm

hey guys

this great info for repairing pitted fork tubes but I seem to have the same "weeping" problem on the right fork only. I had them rebuilt last year at the local Honda shop and they reported everything looked great. as we are in the midst of winter up here in Canada and I have not been riding since October could the seals just be cold therefore not sealing properly? I am hoping as it warms up and the bike gets some exercise again it will stop???? do you think I am on the right track or do I need to pull apart the front end again and have them gone thru again?

thx
kent
kbart1
ICOA Member
ICOA Member
 
Posts: 193
Images: 63
Joined: Mon Apr 18, 2011 6:16 pm
Location: Burnaby, British Columbia

Re: Seeping Fork Seal

Postby Larry Zimmer » Sun Mar 02, 2014 2:54 pm

NobleHops wrote:OK, this is freaking AWESOME CONTENT. I totally wish I had a set to try it on. I bet this would work on brake pistons too. I had an otherwise tasty piston with one big pit. Perfect candidate. I think I still have it, if so I'm going to order some of this stuff and try it.

I saw a local auto stereo installer dude with a teeny propane soldering torch, which fit in the palm of his hand. Snapped on with a trigger, full heat instantly, fine flame tip, instant off. That would work perfectly with this. I want one of those! I have no feel for my electric soldering gun...

N.


Nils, and all,
Those little torches can be had at Harbor Freight for under $10. They operate on butane. Just the thing for this type of job.
Larry Zimmer
ICOA Web Post/Pix/Video Archive Mgt
ICOA Web Post/Pix/Video Archive Mgt
 
Posts: 737
Images: 144
Joined: Mon Dec 15, 2003 3:32 pm
Location: Brighton, Mich

Re: Seeping Fork Seal

Postby Larry Zimmer » Sun Mar 02, 2014 3:01 pm

Kent,
I suggest two things: 1) Check the fork sliding area closely for any scratches-axial markings; 2) wait for 45F or warmer and give it another look-see. Seals can get a bit non-compliant when things get into the below 30F range. It is very possible that the dealer didn't do any scratch inspection/repair. If he didn't list it as a separate item on the billing, he probably did not do it. While old age can be a cause of seal weeping, some sort of surface scratch from normal road dust abrasion is often involved. Often can be corrected by some proper polishing.
Larry Zimmer
ICOA Web Post/Pix/Video Archive Mgt
ICOA Web Post/Pix/Video Archive Mgt
 
Posts: 737
Images: 144
Joined: Mon Dec 15, 2003 3:32 pm
Location: Brighton, Mich

Re: Seeping Fork Seal

Postby kbart1 » Sun Mar 02, 2014 3:11 pm

thanks Larry

I agree with you and am hoping to wait until it warms up a little and check it. until then I'll just keep soaking it up and top off when warmer and see what happens. hopefully we'll be out riding soon. snowing today on the west coast of Canada which actually is pretty unusual.

thx
Kent
kbart1
ICOA Member
ICOA Member
 
Posts: 193
Images: 63
Joined: Mon Apr 18, 2011 6:16 pm
Location: Burnaby, British Columbia

Re: Seeping Fork Seal

Postby NobleHops » Sun Mar 02, 2014 11:46 pm

Kent,

Sometimes the seals are totally fine, but a teeny bit of debris gets lodged between the seal and tube. In that case there was an old trick with 35mm film that folks did, but in lieu of that, there is this product too:

http://sealmate.net/

It's short money to buy it, and good thing to have in the toolbox, why not give it a try?

N.
Nils Menten
Tucson, Arizona, USA

'80 CBX, sort-of restored :-)

http://noblehops.smugmug.com/Motorcycles/The-Not-Restoration-of-My/5334012_jN2Rnx
User avatar
NobleHops
ICOA Member
ICOA Member
 
Posts: 2416
Images: 28
Joined: Mon Jan 25, 2010 8:17 am
Location: Tucson, Arizona, USA

Re: Seeping Fork Seal

Postby Larry Zimmer » Mon Mar 03, 2014 12:08 pm

For $5 and a quick try, this is great, Nils. And, if it doesn't work, only out $5 and 10 minutes. No farther behind.
Larry Zimmer
ICOA Web Post/Pix/Video Archive Mgt
ICOA Web Post/Pix/Video Archive Mgt
 
Posts: 737
Images: 144
Joined: Mon Dec 15, 2003 3:32 pm
Location: Brighton, Mich

Re: Seeping Fork Seal

Postby kbart1 » Wed Mar 05, 2014 10:07 am

thanks guys

I picked up a couple on line and will try them out. will report back with results.

thanks a lot!
kent
kbart1
ICOA Member
ICOA Member
 
Posts: 193
Images: 63
Joined: Mon Apr 18, 2011 6:16 pm
Location: Burnaby, British Columbia


Return to HANDLING: Suspension, Gearing, Frame Bracing, Non X Handling Part Upgrades, Rim Replacement Options, and more

Who is online

Users browsing this forum: No registered users and 1 guest