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Discussion Starter · #1 ·
I think I need to do some fork maint. on my sporty.

it would appear one of the seals is leaking. one of the upper forks appears to have a black oily substance on it where it goes into the lower fork.. the other fork doesn't seem to have this problem. I imagine I will at minimum need to replace those. also, should i be able to bottom out the folks just with my body weight? they seem to compress REALLY easy.

Is there a how-to on fork upgrade or rebuild procedures i should follow? will i need special tools to pull the forks apart and put em back together? what parts will i need to "rebuild" the forks? is it cheaper and easier to just buy new one's? (that seems expensive). would there be a handling or traction advantage in getting a wider fork/tire combo?
 

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Aging Cafe` Racer
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You need fork seals, heavier springs and some fork oil.

Generaly what you do is loosen the fork cap a little, then take off the front wheel, fender and brake caliper. It's a good idea to have some small wooden wedges to slide between the brake pads, this will keep the brake pistons from pushing out to far and making it hard to re-install. Loosen the pinch bolts on the top and bottom and slide each fork tybe out. Wrap the fork tube in a rag and hold it in a vice ONLY tight enough to screw the fork cap out (that's why you loosen it first)then pull out the fork spring w/o spilling fork oil all over. Turn the whole thing upside down in a suitable container and pump the fork like a shotgun till all the oil is out. Pry off the dust cover from the fork slider then pull the seal out, paying attention to whether there's a difference between the top and bottom of the seal . wipe everything off nice and clean, smear a little fresh fork oil on the new seal and slide it in place, replace the dust cover, slide your new springs in, pour in the correct amount of 20 wt. fork oil, pump the fork up and down slooooowly to get the air out, start twisting the fork cap on bearing in mind there's about a million threads per inch and it's VERY easy to cross thread it, do the same on the other fork leg, reassemble everything, go for a ride and be amazed how much better your forks work.

Two things you need are good tools and a Harley manual, the factory Harley manuals are the best and will go into minute detail. If it all sounds too much then take it in and pay someone. For a Sportster it shouldn't be more than 3 hrs or so labor + parts.
 

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I used to take the cap off my FXR while the tube was held by the tree.

'Course, I already had the PS springs and longer spacer. it took some serious @ss to get the cap on, and the thing wanted to go into low earth orbit if you weren't ready for it when it came off the threads.

I can't do that with the Sprint. No room above the tubes. Just getting the caps loose is a chore. And, everything is soft "aluminium".

One tip; you can put the slider in a vise (clamp the fender mounts with soft jaw pads). One guy puts the box end wrench on the cap and then pushes down on the cap until it makes contact with the tube. The other guy pushes up on the tube while he turns it, and if everything is lined up, the cap threads on nicely. Turn the cap down until it's snug. You get the final torque when you have the tube back in the 'trees.
 

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MODERATOR X
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"splain to me...

You need fork seals, heavier springs and some fork oil.

Generaly what you do is loosen the fork cap a little, then take off the front wheel, fender and brake caliper. It's a good idea to have some small wooden wedges to slide between the brake pads, this will keep the brake pistons from pushing out to far and making it hard to re-install. Loosen the pinch bolts on the top and bottom and slide each fork tybe out. Wrap the fork tube in a rag and hold it in a vice ONLY tight enough to screw the fork cap out (that's why you loosen it first)then pull out the fork spring w/o spilling fork oil all over. Turn the whole thing upside down in a suitable container and pump the fork like a shotgun till all the oil is out. Pry off the dust cover from the fork slider then pull the seal out, paying attention to whether there's a difference between the top and bottom of the seal . wipe everything off nice and clean, smear a little fresh fork oil on the new seal and slide it in place, replace the dust cover, slide your new springs in, pour in the correct amount of 20 wt. fork oil, pump the fork up and down slooooowly to get the air out, start twisting the fork cap on bearing in mind there's about a million threads per inch and it's VERY easy to cross thread it, do the same on the other fork leg, reassemble everything, go for a ride and be amazed how much better your forks work.

Two things you need are good tools and a Harley manual, the factory Harley manuals are the best and will go into minute detail. If it all sounds too much then take it in and pay someone. For a Sportster it shouldn't be more than 3 hrs or so labor + parts.
Splain to me Lucy how you get the seal out/in while the slider/lower fork leg is still bolted together?

Don't forget to tell him to un-bolt the damper assy, by removing hex head thru-bolt located in the bottom of the fork leg, where the axle goes.
 

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I was gonna ask about the "smear a little fresh fork oil on the new seal and slide it in place," since I've never been able to do that.

My experience usually involes brute force and cursing!

AFA the damper bolt, I like to use an air impact wrench.
 

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Once the damper rod bolt is out (and you've removed the dust-wiper and seal lockring) it's easiest to just "knock them apart" with a slide-hammer-like action.

If the damper rod spins while trying to remove the bolt, take it out of the vice, push a broomstick up its arse and use THAT to hold the damper rod in place whilst loosening the bolt.

Or, you can just loosen the damn damper rod bolt before removing the fork cap, like you're supposed-to (but I forget it myself, about 50% of the time!).

Under NO circumstances are you to replace your current seals with the "Leak Proof"-brand POS's!!

They Leak. And will scratch your sliders, and sleep with your Wife, drink your beer, and kick your dog.
 

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Aging Cafe` Racer
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by golly I did miss that bit didn't I......

See kids, that what happens when you're goofing off on the computor when you're supposed to be watching the plant!!


Let that be a lesson to you
 

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by golly I did miss that bit didn't I......

See kids, that what happens when you're goofing off on the computor when you're supposed to be watching the plant!!

Let that be a lesson to you
And I forgot to mention that, when re-assembling the forks, you put it all back together, THEN gently slide the seal in place, tapping it into its seat with a suitable driver.

The cheapest/best seal-drivers are pieces of PVC pipe, of a suitable diameter (or couplings - a sch.-40 1-1/4" coupling with the "divider" cut-out with a pocketknife works perfectly on a 41mm fork). If you can't find one that's "perfect", find a piece that's slightly too-tight to go over the slider (and inside the stanchion!) and saw one side lengthwise. Fit it over the slider, a few wraps of duct-tape, and - Urethra! There it is.

I don't have to tell you to use a soft hammer around your forks, do I?
 

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Discussion Starter · #12 ·
thanks for the response guys.. i saw the "leak proof" seals on the jpcycles site and my snake oil detector went off the charts.. i thought leak proof was the point of having a seal in the first place.

i'll have to sort out access to a vice.
 

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The Toad
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thanks for the response guys.. i saw the "leak proof" seals on the jpcycles site and my snake oil detector went off the charts.. i thought leak proof was the point of having a seal in the first place.

i'll have to sort out access to a vice.
I hate to harp on it but if you are going to be doing your own Sporty maintenance then you'd better get manuals for it. The factory manual is not expensive. At least it wasn't when I had my sporty.
 

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If you insist: "Gosh, Findangle, a bottle of wind and some flowers might be a better choice since it's only your first date!"
What kind of gropes is wind pressed-from?
 
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