Harley Davidson Sportster 39 mm Front Fork Removal, Disassembly, and Rebuild

The front forks were leaking on the 1990 Sportster, enough that there was a puddle of fork oil on the lift. In this video I walk through removing, disassembling, and rebuilding the 39mm front forks on my Harley Davidson Sportster. To rebuild the forks the fork seals, dust covers, fork seal retaining clips, o-rings, and damper bolts will be replaced.
I am rebuilding these forks due to them leaking past the seals (likely due to them not being installed correctly in the first place - missing retaining clips on the fork seals) but this same process would be used if you were replacing the fork tubes (adding longer tubes for example).
Man it was hot in the garage. The process for removing, disassembling, and rebuilding the front forks is not too difficult, but I was sweating like you wouldn't believe. Can't wait till this heat breaks.
Pinch bolts are tightened to 30 ft/lbs. Added 10.2 fluid ounces of fork oil to each rebuilt fork.
Motion Pro 39mm Fork Seal Driver: amzn.to/3sy4mkV (Affiliate Link)
39mm Fork Seal Kit: j-and-p-cycles... (Affiliate Link)
Fork Oil: amzn.to/3gg1J2f (Affiliate Link)
1986-2003 Sportster Repair Manual: amzn.to/3j4tnAX (Affiliate Link)
#Sportster
#forkseals
#rebuild
#HarleyDavidson
T-Shirt from Maui Brewing Company: mauibrewingco....
This is the second video I have done with multiple segments and then edited them to stitch them together. Not going to win any awards but I think I did a bit better on this one. I'll learn more as I go.
Visit www.sportsterpr... for more...
Build. Tinker. Ride.

[@kd1542]

Nice video. I would have also replaced the bushings while you had the forks apart. I don't understand why you didn't fill the forks with fork oil before installing the caps but no big deal. I usually loosen the caps a little before removing the fork tube from the clamps.

[@BabySteev]

Hey thanks for taking the time on this. Gave me confidence to get at’er.

[@hooshangmaster]

it's my first time doing the seals. how long did it take you?

[@LuisHernandez-fo3pv]

Helpful video but i think you should always start putting any plug by hand first to avoid cross threading. It would help showing that and explaining it so someone else doesnt ruin the bottom fork

[@rickdee67]

Break the top cap loose and knock the dust cover loose before removing the fork from the triple trees. Good video.

[@randallissimo]

Good instruction. Thank you.

[@veronicastewart1959]

Glad I found your video, I have a 2008 Sportster 1200 and my dust caps have rusted I know I need to do what you did with mine. I wanted to know in mine has the same size bolt 39mm . ( nut.) Thanks for sharing your video I believe I can do mine. I do have a question, what size pvc pipe could I use? Thanks again from Mobile, Alabama

[@g-loctv6114]

Do you have to wait until the forks are back on the bike before you add the oil? Or can you add the oil before installing the forks back?

[@nightmaremike1092]

Bro seriously thank you so much this has to be the BEST video hands down more simple then this it doesn’t get cant wait to fix my leak 👊🏻

[@lexustech48]

Great video sir, earned you a sub! Hopefully picking up a nice little 2007 XL50 tomorrow! Not sure if I want to Club style the bike yet, but I definitely want to convert to a dual front disc setup! Your video should help make that easy. Thanks again!

[@eggxeiber]

Great information but you need somebody to help with the camera, that going to help you thank you.

[@willcountypowersports6338]

Curious on what that hose is coming out of your cam cover? Is that a breather mod running to their?

[@owenwilson7138]

if you're refilling the forks from "dry" isnt 11.6 oz of fork oil?

[@aimen_a]

Thank you for the content, very clear

[@SportsterProject]

Thank you. Glad it was useful.

[@pastorbobncc365]

Great teaching my friend have a blessed week

[@churchtech9681]

Thanks so much for posting this video.

[@vikerbikeruk]

nice video sir..well done I was not sure were tyhe small spring went lol

[@joerodriguez9752]

Very helpful brother ty I just seen mine leaking

[@SUPPORTYOURSELF]

Great video, thanks for the help!

[@kennethrutt7986]

Wish mine was going as well...my fork caps are not comming off, even with a 3 ft helper bar.....I think I am to the point of using head...or cutting the bolt head for smaller socket, as the edges of the bolts gave out and my 1 3/8 no longer works....might try a 34mm before cutting...but dang, you all make it look easy.

[@andawayigorollinlikeadonut1986]

Spay with pb blaster first and a 35mm socket with braker bar put some tape over fork caps and turn to the left they will come off.

[@kennethrutt7986]

@@andawayigorollinlikeadonut1986 Thanks for the suggestion, finally got them off, looks like the previous owner had put pipe dope on the threads.

[@josedaniel4725]

Installing them back, do you have to mark them to make sure they are even? I'm polishing mine but have to ask before I wreck myself 😁

[@LuisHernandez-fo3pv]

You can just mark one side and slide them in without fully tightening them down and just bolt the wheel on and it'll even the forks

[@ACoustaDC]

Great video. I thought a 90 sporty would be belt driven... did you convert that to chain drive?

[@SportsterProject]

Yep I converted it to a chain drive.

[@viergarcia]

Exactly the vid I needed.

[@firstsecurechoice202]

Thank you

[@nealraudabaugh7922]

@sportster project great video man. Don't you have to drive the upper bushing into the slider tube until its seated and then drive the seal on? Maybe to not damage the seal by using it as a bushing driver

[@SportsterProject]

Neal, Thanks for the feedback. I guess that would not be a terrible idea if needed, but I have never had the upper bushing and spacer not just fall into place. Not sure you should need to drive it in, at least I can't think of anytime I have ever had to. There is a spacer that sits between the top bushing and seal to keep the seal from hitting the bushing. Probably worth checking to make sure it is seated before hammering the seal home.

[@levimellen9649]

I'm having trouble getting bushings far enough in to get seal in enough for the clip. Any advice?

[@garageassembled4701]

Very helpful

[@dedalo06]

Can we use synthetic motor oil same sae as hydraulic fluid instead for the forks? is really a bad idea?

[@SportsterProject]

I have no idea whether this is a bad idea or not. I have always just used fork oil.

[@kd1542]

Fork oil is different than motor oil and normally you need a thinner fork oil (5 or 10 wt) than what you run in your motor (20W50).

[@supaman396]

Thank you

[@Ialicea5840]

thx u

[@jasonjohnson3577]

Great!

[@lawrencebrandt8448]

amateur

[@SportsterProject]

Yep