Weeping Fork Seal

[AndyH]

I just got my forks overhauled for the first first time since I got the bike (do most stuff myself but there was some work needed on stripped/seized fastener threads so while I was at it...). There's slight weeping in the fork seals leaving a black tide mark, more on the left than on the right, after a run which shouldn't happen this soon after seal replacement. I should get through the annual MOT next month, if I wipe down first but I want to fix in the longer term.

 

The bike's got 16K miles on the clock, but I don't know how long it was run without a odo/speedo and I'm sure it had somewhat more than that. Looking at the fork stanchions I suspect the problem is a worn hard chrome surface: no pitting but it's just a bit too shiny on the front, perhaps from being run for too long with too little oil and no overhaul. On the other hand, it may be just a problem with this generation of fork (2000).

 

If the former is the case, outright front fork stanchion replacement will be expensive. Some specialists offer a fork rechroming service for normal forks, but for upside-down? Is this a cheaper option or even possible?

 

Anyone with any experience of this? If you know of a good such supplier in the UK, let me know.

 

AndyH

[Baldini]

I've had "right-way-up" stanchions re-chromed by HCP&G in the past. http://www.hardchromeplating.co.uk/location.cfm

Did a real good job. Not cheap. Don't see why they wouldn't do USD.

 

KB

[AndyH]

I've had "right-way-up" stanchions re-chromed by HCP&G in the past. http://www.hardchromeplating.co.uk/location.cfm

Did a real good job. Not cheap. Don't see why they wouldn't do USD.

 

KB

Thanks, I'll check them out.

Happy with their work?

 

I found www.pittedforks.co.uk which are actually just up the road from me in Hemel but have not yet found any recommendations online for the quality of their work. Proximity alone is not necessarily the best criterion for selecting a supplier.

 

Anyone know of issues with Marzocchi forks on this generation of V11 Sport? 'Cos there's no point in expensive rechroming if the seals are a slack fit in the first place.

 

AndyH

[GuzziMoto]

No issues here with the Zokes on the wifes 2000 V11. 50 some thousand miles with original seals. I have modded them to get actual compression dampening out of them but the seals are original.

Not sure about your description of "worn chrome". Usually if there is a problem with the chrome tubes causing seals to leak it is pitting, not being "too shiny". Also, a little oil making its way past the seal, just enough to make it so you can see where the seal has been, can be an early sign of the seal going but unless it is actually leaking I would not replace it unless you are getting ready to go on a long trip and just want to be sure. It could turn out to be nothing. Or either the replacement seal was not up to snuff or the seal was nicked on install.

You could measure the tubes with a micrometer for out of round wear, comparing the results to other bikes that do not leak. But the chrome layer is pretty thin and and real wear would likely go through the chrome, resulting in less shine not more, I would think.

[jrt]

If you want to look overseas, we have 'Forking by Frank'.

http://www.frankmain.qpg.com/

No idea what the prices would be though.

[Tom M]

Do you know if the shop that overhauled your forks used Marzocchi seals? Aftermarket seals don't always work as well as OEM.

 

FWIW mine are still good at 36k miles.

[HaydnR]

There is also:

 

http://www.allbikeengineering.co.uk/html/forks.html

 

which has a good reputation.I have no personal experience though.

[AndyH]

Do you know if the shop that overhauled your forks used Marzocchi seals? Aftermarket seals don't always work as well as OEM.

 

FWIW mine are still good at 36k miles.

I was beginning to wonder if that might be the problem... could well be it as I have no provenance for the seals - they could have put the old ones back in for all I could tell.

 

There really isn't any pitting on the chrome and the tide mark is just a bit too obvious to be certain to pass an MOT test unless I give it a wipe down round the corner before I take it in.

 

Cheapskates! Just goes to show, if you want a job done properly, do it yourself (although to be honest I didn't have the pillar drill to drill out the stuck fasteners accurately)

 

AndyH

[AndyH]

There is also:

 

http://www.allbikeengineering.co.uk/html/forks.html

 

which has a good reputation.I have no personal experience though.

Hmm! Just looked at this...

 

"Titanium Nitride coating available."

 

What's that, anyone?

[GuzziMoto]

It is that pretty gold color instead of chrome for the sliding surface of the tubes.

It is supposed to be lower friction then chrome. It certainly looks cool. There is also a black coating available now. That is what the forks on my Daytona (from a GSXR) have.

[AndyH]

It is that pretty gold color instead of chrome for the sliding surface of the tubes.

It is supposed to be lower friction then chrome. It certainly looks cool. There is also a black coating available now. That is what the forks on my Daytona (from a GSXR) have.

There's a thought. Is the black coating a kind of metallic black/gunmetal type colour or just gloss black? Don't recall having seen it?

A

[GuzziMoto]

I think it is mainly a Suzuki thing. They call it DLC (Diamond Like Coating) as I recall.

It appears to be mostly a black chrome, but I am sure it is not really that simple. It is supposed to be a very hard surface and also slippery. I don't know about that, mostly I think it looks cool. If it is harder and/or more durable then chrome, great. But I just like the blacked out look.

You can buy a used set of GSXR forks complete with brakes and rim for cheap. I spent $600 on mine. I then sent the forks to a suspension guy and had them revalved and sprung for the Guzzi. To fit them o the Guzzi frame only required a different set of steering head bearings. I used some for a DRZ. The whole deal was under a grand, and the improvement in the front suspension is huge. The stock Zokes are ok but leave a fair bit of room for improvement. The first gen V11 forks do not even have adjustable compression dampening. The adjuster on the compression fork actually adjusts a hydraulic bump stop. It only affects the last inch of travel.

[GuzziMoto]

Oh, I also had a thought while working on my bike.

When fork seals are installed it is common, at least in my experience, to use a seal grease on the new seal. This can cause a ring to be left around the tube where the seal has recently been to. It could be hard to tell the difference between that and a leak. Is this ring you are seeing definitely wet? Do you wipe it off with a white rag? What color is it? Do you use a cleaner to remove it or just wipe it off?

[AndyH]

Oh, I also had a thought while working on my bike.

When fork seals are installed it is common, at least in my experience, to use a seal grease on the new seal. This can cause a ring to be left around the tube where the seal has recently been to. It could be hard to tell the difference between that and a leak. Is this ring you are seeing definitely wet? Do you wipe it off with a white rag? What color is it? Do you use a cleaner to remove it or just wipe it off?

Yes, I just wipe it off and it's black. Pretty sure it's fork oil and road dirt. I've done 500 miles or more since the overhaul and the tide mark keeps coming on the left (stopped on the right, so there could be something in what you say?).

[GuzziMoto]

I like to spray brake clean on a rag and use that to wipe it off. The brake clean does a better job of cleaning the tube and spraying it on a rag instead of the tube allows you to control where it goes.

It could be the seal grease from what you said, I would give it more time with cleaning. Maybe you should talk to the guy that replaced the seals to get his opinion.

You could also pull the wiper ( that first outer part of the seal that you can see, that actual seal is deeper inside) and see what is under there. If it is fork oil it would likely be wet under there, if it is grease it will just be..... well, greasy. Just be careful.