*pic* Black Streaks on Inner Fork Tube

Fellas, I'm new to the off road bike scene, but I'm no newbie.

I've never seen this on any of my other motorcycles, so I'm hoping you guys have seen it on your bike at some point.

I have black streaks that appear lengthwise on my inner fork tubes.

IMG_3408.jpg

What causes this? How do I remedy the problem? Is there a way to remove them?

I bought my bike used, and the more I look at it, the more I realize it's been beat down. 2007 DRZ400SM.

Thanks guys!

I think it has been beat those marks look like the plating has been worn off. I've seen this happen when using seal savers. If thats what is happening its not good

If the plating is worn off, then yes, that's brutal... BUT!!

It's got 2900 miles, so I doubt that's the case. It's tough to tell from the pic, but it's more of a "stain" than a rub mark. It's so weird.

I'm hoping it's more along the lines of this:

Travis_D-37

09-09-2003, 12:11 AM

Black marks on the tubes right? If so your tubes are not alined properly. Loosen the pinch clamp opposite the axle nut and push the forks down hard 6-10 times. This will aline the tubes. Tighten the pinch clamps and ride.

Have you tried to use a solvent to see if they come off?

Have you tried to use a solvent to see if they come off?

+1

nice carbon fibre fork guards btw:thumbsup:

I would try to clean them up.

Then loosen the entire front end, axle, pinch bolts, triple clamps, and re-align everything. If the fork tubes were not parallel with one another, the seals or wipers could be rubbed excessively, causing them to heat up and leaving those streaks.

Once clean and aligned, see if the problem persists. My vote would be the tubes are not parallel.

I would try to clean them up.

Then loosen the entire front end, axle, pinch bolts, triple clamps, and re-align everything. If the fork tubes were not parallel with one another, the seals or wipers could be rubbed excessively, causing them to heat up and leaving those streaks.

Once clean and aligned, see if the problem persists. My vote would be the tubes are not parallel.

Thank you for a beauty response!

I've already gotten the bike up on a lift, and have removed the forks. I then rolled them both along a smooth granite counter-top (m'lady was excited about that), to check that they're straight. They are.

I think it's high time for a teardown and rebuild on these things anyways.

Appreciate all the responses guys!

Just found this nugget too...

Re: Polish fork tubes at home?

eddie if you have the dark vertical markes on your tubes make sure you look at your bushings for wear----i replace alot of the tube and slider bushings in kybs and showa------ mx is very hard on them

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