Fork Tube Coating/Refurbish

hubbardmx50
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Rancho Cucamonga, CA US
11/13/2019 9:21am
Hey guys, my dad has a 2010 Ducati Hypermotard that has been giving him a hell of a time for awhile now. He’s been through about four seals on his right fork leg and we can’t seem to figure out. I do the suspension on all of our moto bikes and scotch bright always does the trick for a leaking seal. But clearly there’s a bigger problem on this fork leg and he’s had it. Ducati does not sell the tube individually and the only seller on eBay who had some was in France and sold them all. Does anybody know of a company that could possibly refurbish and or coat the leg for him? I’m trying to get a hold of Enzo today with no luck yet. We’re in SoCal but don’t mind to ship. Thanks
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kb228
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Mansfield, OH US
11/13/2019 11:25am
Have you ruled out worn bushings yet?

Any suspension shop that does coatings should be able to do it for you. The suspension isnt that much different compared to an mx bike.

hubbardmx50
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Rancho Cucamonga, CA US
11/13/2019 11:40am
kb228 wrote:
Have you ruled out worn bushings yet? Any suspension shop that does coatings should be able to do it for you. The suspension isnt that much...
Have you ruled out worn bushings yet?

Any suspension shop that does coatings should be able to do it for you. The suspension isnt that much different compared to an mx bike.

I'm not sure if he replaced the bushings, good question. My question is which shops do the coatings, I've never had it done or payed attention to who is currently doing it.
kb228
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11/13/2019 11:55am
Factory connection and rg3 do dlc coating.
dkurtd
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TN US
11/13/2019 2:27pm
Racetech.

The Shop

Luxon MX
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San Diego, CA US
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11/13/2019 3:00pm
We do DLC coatings as well, but that won't fix what you're describing. DLC and other PVD coatings (TiN, etc.) are all very thin, only a few microns. They won't fill in any nicks, dents, or scratches at all.

You will have to polish out the affected area, then coat it. But if you removed too much material in polishing you'll still have issues. It depends on how deep the problem is whether or not it can be fixed. Some people have had luck filling it with JB weld or similar and sanding it down. That's probably worth a shot first.
captmoto
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Rancho Cucamonga, CA US
11/14/2019 12:06am
Just look for hard chrome replating in your area. Usually hydraulic cylinder repair places are a good place to start. The old chrome is ground off and then replated and finish ground to tolerance, a similar process to cylinder replating.

https://www.youtube.com/watch?v=z5goYiEF5Ig

There is another newer process where the plating material is shot on under high pressure.

https://www.youtube.com/watch?v=R8-aibcofM8
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mxtech1
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Galesburg, IL US
11/22/2019 6:05pm
The issue isn't the chrome coating on the lower leg.

Your problem is what's referred to as shaft to bore misalignment (STBM). STBM is induced by the centerline of the shaft (lower leg) and housing bore (upper housing) not being on the same plane.

The most common cause for this issue is a bad/worn set of bushings. Another issue can be a bent lower fork tube, say from hitting a pot hole or doing too many steppes over time. To check lower and upper tube straightness, you have to rotate them through 360 degrees on V-blocks while measuring with a dial indicator.

My advice.....buy a full set of OEM bushings and seals and the problem will likely be solved.
DrewJett747
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Belleville, IL US
12/27/2019 10:15am
Did you ever resolve this issue? I've been dealing with leaky for seals on my KX450 for some time now and I'm about to give up. Ive had the fork seals and bushings replaced 4 times in less than 20 hours and nothing seems to be fixing my issue.

What I do know is that the bushings look trashed after a few hours of riding (copper color is worn off), the oil is silver in color and the seals appear to be in good shape. Ive used an assortment of replacement parts and I've even ordered OEM Kaw seals and bushing for the last installation. The dlc on the lower shafts appear to be in great shape and i had racetech re hard anodize the fork tubes in fear that inner factory silver ano was defective and contaminating the oil.

I'm open to suggestion
harescrambled
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Warren, OH US
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12/27/2019 4:10pm
Did you ever resolve this issue? I've been dealing with leaky for seals on my KX450 for some time now and I'm about to give up...
Did you ever resolve this issue? I've been dealing with leaky for seals on my KX450 for some time now and I'm about to give up. Ive had the fork seals and bushings replaced 4 times in less than 20 hours and nothing seems to be fixing my issue.

What I do know is that the bushings look trashed after a few hours of riding (copper color is worn off), the oil is silver in color and the seals appear to be in good shape. Ive used an assortment of replacement parts and I've even ordered OEM Kaw seals and bushing for the last installation. The dlc on the lower shafts appear to be in great shape and i had racetech re hard anodize the fork tubes in fear that inner factory silver ano was defective and contaminating the oil.

I'm open to suggestion
Bent upper or lower fork tubes, triple clamps twisted from impact, bent axle will all cause these symptoms. Is the wear on your bushings all around, or only on one side? Did the bike do this from brand new, or did it start after a crash? You'll need to check all the elements I mentioned with V blocks and a dial indicator to rule them out as the cause.
BikePilot
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Golden, CO US
12/31/2019 6:47am
Maybe obvious, but improper install of the front wheel will pinch the lower fork legs together and trash seals and bushings in short order. Make sure to pump the front end up and down after tightening the axle and before tightening the pinch bolts.
1
jaredkeller96
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504
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Huntersville, NC US
12/31/2019 6:53am
Did you ever resolve this issue? I've been dealing with leaky for seals on my KX450 for some time now and I'm about to give up...
Did you ever resolve this issue? I've been dealing with leaky for seals on my KX450 for some time now and I'm about to give up. Ive had the fork seals and bushings replaced 4 times in less than 20 hours and nothing seems to be fixing my issue.

What I do know is that the bushings look trashed after a few hours of riding (copper color is worn off), the oil is silver in color and the seals appear to be in good shape. Ive used an assortment of replacement parts and I've even ordered OEM Kaw seals and bushing for the last installation. The dlc on the lower shafts appear to be in great shape and i had racetech re hard anodize the fork tubes in fear that inner factory silver ano was defective and contaminating the oil.

I'm open to suggestion
Sounds like you have a knick in your fork tube...
1
DrewJett747
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5/22/2018
Location
Belleville, IL US
1/2/2020 9:15am
Did you ever resolve this issue? I've been dealing with leaky for seals on my KX450 for some time now and I'm about to give up...
Did you ever resolve this issue? I've been dealing with leaky for seals on my KX450 for some time now and I'm about to give up. Ive had the fork seals and bushings replaced 4 times in less than 20 hours and nothing seems to be fixing my issue.

What I do know is that the bushings look trashed after a few hours of riding (copper color is worn off), the oil is silver in color and the seals appear to be in good shape. Ive used an assortment of replacement parts and I've even ordered OEM Kaw seals and bushing for the last installation. The dlc on the lower shafts appear to be in great shape and i had racetech re hard anodize the fork tubes in fear that inner factory silver ano was defective and contaminating the oil.

I'm open to suggestion
Bent upper or lower fork tubes, triple clamps twisted from impact, bent axle will all cause these symptoms. Is the wear on your bushings all around...
Bent upper or lower fork tubes, triple clamps twisted from impact, bent axle will all cause these symptoms. Is the wear on your bushings all around, or only on one side? Did the bike do this from brand new, or did it start after a crash? You'll need to check all the elements I mentioned with V blocks and a dial indicator to rule them out as the cause.
The wear on the bushing is uniform, nothing obvious. I originally had PC valve the forks back in 2015 and they were pretty reliable. When i bought my 2018 i sent the forks back to PC and had the spring conversion done. Between both bikes the forks have roughly 80 hours on them, 50 as air forks and 30 with the spring conversion. The forks were leaking a little bit when i had them set up as an air forks but since they've been switched over to spring forks they've puked oil. I'm not sure if something was damaged or if the tolerances of the spring kit are junk. Ive had Race Tech, ProCircuit and a local suspension guy clean, inspect and replace the bushings and seals and all of them have leaked.

I'm a stickler for pumping and torquing the front end so i know the front end isn't binding. Its a good observation though.



BikePilot
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Golden, CO US
1/2/2020 10:05am
That's crazy, to wear the bushings out so fast I'd think that something has to be binding somewhere. Clutching at straws here, but maybe loosen and re-torque the upper and lower triple clamps (including stem nut) to make sure they aren't mis-aligned or over-tightened? I usually torque the lower triple clamp bolts to 2ft lbs less than whatever the recommended torque is to help make sure I don't pinch them in on the bushings. I've also seen upper tubes get ovalized (front to back) and result in leaks and rapid bushing wear. I've only seen this on really high-hour bikes that have had hard lives (crash/over-jump prone A riders) though.
crowe660
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US
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9/24/2021 5:34pm Edited Date/Time 9/24/2021 6:40pm
Not sure if you ever resolved your issue, but I just happened to come across this thread. I've been doing hard chroming for a decade for a gage manufacturer.

I've never plated motorcycle fork tubes, but I've plated 10's of 1000's of OD/ID rings and tubes of all sizes .25 up to 16" and can accurately plate to within .000010 millionths.

If anyone has any extra fork tubes they want to send me, I'd really like to try re-chroming some. I can measure and then strip off original chrome and re-plate to the original thickness. I'd prefer to do this on an extra set that might have otherwise been thought of as trash if possible lol...

I'm not trying to make money of this either.. Just want to see if I can help. jcrowe660@gmail.com

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