How-To: Rebuild XS650 Forks / Install Lowering Kit

[Punkskalar]

Alright gang, I've been working on these for a while, and after all the requests and emails, I'm finally getting time to get this How - To up for us If you are only planning to rebuild your forks, disregard all the stuff about the lowering spacers and cutting the springs.


Lower those XS650 Forks! (This is for 35MM Forks only, 34MM Forks are very similar, and can be disassembled the same way... Check my blog for more information on 34MM Lowering kits as well)

You'll need the following tools:

8MM Deep Reach Allen Socket (Make one yourself on the cheap, just cut an old allen wrench)
17MM Fork Cap Tool (Grab an old 17MM Headed Bolt, weld it into a socket on the cheap!!)
2MM Allen Wrench
Modified 17MM Socket (Early forks only - See Below)
LONG 3/8" Extension or a pile of short ones
3/8" Ratchet, breaker bars, etc...
Impact Gun (Not necessary, but might save you some work)

You'll need the spacers as well: I've been trying like crazy to find a suitable way to lower these forks AND keep the valving ports operating, and these are what I have finally come up with. Fully Lathe Machined 6061 Aluminum, with Valving Ports and a Set Screw to keep them in place I can make these for you in ANY drop from .5"-3"

You can find these parts and more on my Blog - http://hughshandbuilt.blogspot.com/

OK, let's get started - (Once you have the forks removed from the trees, I'm not gonna show how to loosen up 3 Bolts and Remove a wheel, this is easy stuff)

There are 2 types of 35MM XS650 Forks, Early and Late style. Here is a quick glance at how to tell the difference. The internals will be different as well, but I will cover modding both types

I'll start with the "Late Style" forks and add the information for the Early Style a little further on.

If you get REALLY Lucky, you can remove the lower from the upper just by using an impact gun and the deep allen on the bolt in the lower leg.
(Homemade Tool Mentioned Above)

The Lower Leg Bolt

Try the Impact (if you have one)

If that bolt comes out completely at this point, you just saved some work and time. IF the bolt comes out completely, go ahead and pull the lower leg apart from the upper. If not, don't sweat, at least its loose now

Move on to the upper fork cap. Remove it with a 22MM Socket, Wrench, Crescent Wrench, Hammer, etc...

Once it it out, you'll need to remove the small disk that goes over the spring. Should look like this:

TAGS: XS650 XS 650 XS1 35MM Forks Lowered Lower Lowering Slammed Low Rider Chopper Bobber Cafe Racer Hugh Owings Hugh's HandBuilt Hughshandbuilt@gmail.com RE-Phased 277

 

[Punkskalar]

Remove the spring:

Now you'll need the 17MM Socket Cap thing I mentioned above. Basically just a 17MM headed bolt welded to an old socket.

I couldn't get a good picture, but stick your 17MM Tool on a long extension (or a bunch of extensions, whatever works for ya) and insert it into the upper fork tube until you feel it "lock" into place.

Now hold the lower bolt and remove the bolt holding both tools at the same time. Get a friend if you need one, its not that hard, but it is a bit awkward.

At this point, you should have an assembly that looks like this:

Pull the upper apart from the lower, and your upper should have a dampening rod that looks like this sticking out of the end of it:

Might need to use that long extension to work it out, but the rod should come out looking like this:

If the spring is still in the fork, go ahead and work it out as well. If not, go ahead and pull the spring off the dampening rod.

Now you might have to go fishing in the lower, but you need to work out this little coned spacer:

 

[Punkskalar]

Now you can take your lowering spacer and mock it up on your dampening rod. MAKE SURE THE HOLE LINES UP!

Slide the spacer onto the dampening rod:

Once the hole is lined up properly, lock down the set screw using a 2MM Allen Wrench. Don't strip out the threads, just snug it down. It won't hurt to add a little red locktite if you want.

Now install the top-out spring back onto the dampening rod:

Should look like this compared to a stock setup:

Now slide the whole assemble back into the upper fork leg.

Once you have it all worked into the upper fork, the other end should look similar to this:

I like to use a little bit of tacky grease to hold the conical spacer in place during assembly:

 

[Punkskalar]

Now it is time to attack the upper fork tube. Remove the old rotten seals and dust boots if you want. Not necessary if you already have decent parts, but most are old and cruddy:

Go ahead and remove the retaining spring:

And the upper spacer:

And the old cruddy seals, you might have to grab them with pliers, screwdrivers, etc.. Just get them out without damaging the legs. (told ya they were gross, most are if they haven't been replaced)

Clean up the lowers as nice as you feel your build requires. I can shave and polish the lowers for customers, but how nice you make the lowers is all up to you at this point. Make sure to clean out the old oil and grease inside them while you are in there.

New Seals and such go back into the forks in this order:

Install a new dust boot:

Now you are ready to re-install the lowers to the uppers. Slide the 2 assemblies together like this:

Reinstall the lower leg bolt (there is usually a copper washer here, you can replace it or not, just make sure it is still there!!)

Tighten up the bolt again while holding the upper in place just as you disassembled it:

Now you need to remove some spring material. You can remove up the amount that you are lowering the bike. (IE 2" Lowered, 2" Removed from Springs, etc...) For a firmer ride, you can remove less and experiment with the ride until you have it just right. I use a 4.5" Angle Grinder with a CUT-OFF Wheel (not a grinding wheel, there is a difference)

Install your shortened spring back into the legs. It is best to install the cut end towards the bottom of the fork, so that the flatter end is at the cap.

Re-Install the flat disc:

Re-Install the fork cap:

AT THIS POINT, THERE IS NO OIL IN THE FORK!!! I Usually install the forks into the trees back on the bike, remove the cap, and pour in the proper amount of oil (about 175ML) while the forks are upright, its just easier that way.

If all went well, you should have a nicely rebuilt, lowered fork that looks similar to this:

 

[Punkskalar]

FOR THE EARLY STYLE FORKS!! THERE ARE ONLY SLIGHT DIFFERENCES

When you remove the cap from early forks, there will be a spacer under it. This spacer is 1.5" long or so. You can remove the cap using the same 17MM tool mentioned above.

Spacer:

Remove the springs just as you would in the later style forks. If the impact gun removed the lower bolt from the lower fork leg, then you can pull the forks apart just like the later style forks.

IF NOT, you'll need to make a tool. Take a 17MM 6Pt. Socket and modify it to look like this with a grinder and a cut off wheel, dremel tool, claw hammer, whatever it takes. It's ugly, but it works.

Using the long extension and ratchet, you'll need to feed the new tool into the upper and lock it into place, you should feel it it you made the tool just right.

Loosen the bolt in the lower leg just as you would above, holding this end tight.

This is what the Dampening rod should look like on the early model forks:

And here is how that tool should have fit, but if you got this far, then you made the tool just fine

The Dampening Rod removed (NOTE, there is no top out spring on the early models, it is inside the upper fork tubes and snapped into place via a snap ring. There is not a need to remove it.)

Doing the same procedure as in the later style forks, install the spacer and make sure the valving hole is left open.

Re-Install the assembly into the fork upper:

Tighten it all back down just as you would with the later style forks mentioned above.


NOW, you will need to remove some material from either the spacer, the spring, or both.

If you are lowering more than 1.5", ditch the spacer and remove some material from the spring. If you are lowering less than 1.5" you can just trim the spacer. If you are lowering 1.5" you can just toss the spacer

Reassemble the whole thing just like mentioned above, and you'll have some really nice forks ready to rock :clap for you:


Here is a set of 34MM forks I lowered, shaved, polished, and installed new seals in for a customer. Spend some time on these things and they will look awesome.

 

[Ironsled77]

Very nice again! I guess I got into this too early I had to figure it out myself. This is ever step 650ers! It is that easy.

 

[dqnjuan]

I glad it has pictures about to put an end to my very very leaky front forks.

 

[5twins]

Another method for dismantling the early forks shown above is to use a long length of 1/4" steel rod. The damper rod has a roll pin through it about a half inch down from the top. Flatten the end of the steel rod with a hammer .....

..... and then jamb it down into the top of the damper rod between the roll pin and the side of the tube .....

Make the rod long enough so it will hang out the top of the fork tube and bend it over so you can hold it from turning .....

 

[gggGary]

Thanks for the how to, I finally made a 17mm wrench for the late model tubes. I used a 17mm head bolt and welded a rebar extension with a T handle on it.

 

[Stigda]

Hi, this might seem silly to you but how hard should it be yo insert the new oilseals? They are corrrct size, how can i fix this?

 

[b1broc]

Hi, this might seem silly to you but how hard should it be yo insert the new oilseals? They are corrrct size, how can i fix this?

a old wheel berring i think the front is just a smigint smaller it works awsome for getting in the seals
useing the berring as a press of course

 

[b1broc]

couple light taps a little grease should be nothin but a thing

 

[Capt_Zoom]

Hugh, thanks for the how-to. While I'm not lowering my xs other than the billet top clamp your how-to allowed me to take on replacing the fork seals. Something I haven't done before. What a Pain in the butt getting the old seals out. Other than that all went well.

For the late models, I just took a 2 inch long bolt with a 17MM head and nut and welded the nut onto the bolt. Basically making a dumbell with 17mm heads. I figured this would be easier than wrecking a perfectly good socket.

Thanks again.

 

[Slimbob]

Yo,
Great job with the "How to". Thank you very much. I've never had mine apart either. Just got mine apart. I have a stock 77-D. About 46K miles on her. Not planning to lower mine either but I still have a few questions if you don't mind. I'll upload a couple of pictures soon.
Doing mine on the bike. Just loosened the upper pinch clamps.

Is the the upper tube supposed to have a narrowed OD spot in it? Mine both do and thew look like the may have been overheated somehow. Not pitted but rough, not smoth and dark brown. Will attempt to upload the pics. Take a bit.

Thanks,
Slimbob

 

[Slimbob]

OK, here are some pics of what I was describing on the fork tubes.
Is this indented section unusual?
Also, my dampers alreasdy have 4 holes at the bottom and only 1 small hole at the top. I bought this bike with about 4K miles on it in 1981 from the second owner. I know he never had it apart. I thought the factory dampers had only 2 holes on the bottom.

Thanks in advance for any input,
Slimbob

Sorry, didn't mean to hijack your thread. I'll repost.

 

[Capt_Zoom]

I don't think that's normal. I'd replace them. If it were normal they likely wouldn't seal as well when you replace the fork seals.

 

[strang]

Hugh you are great man, well written and given me confidence to give this a go myself.

Maybe useful for any schmucks like me who can't weld and are about to do this,
I found both of Hughs homemade tools on ebay:

"8MM Deep Reach Allen Socket" - search hex socket 8mm
"17MM Fork Cap Tool" - search hex socket 17mm

cost for both was about £10 delivered.

If you can weld (I don't have a garage) why spend £10 but if you can't (me) this gets you the tools.

 

[jd750ace]

The indention appears in the 24th picture from the top of the thread, and is not mentioned, so I'm assuming it's a normal condition

Look for this wording above the pic:


Once you have it all worked into the upper fork, the other end should look similar to this:

 

[strang]

bollocks - the pics have disappeared!!!!
can this be remedied?

 

[realgone]

I hope so, my HHB lowering kit got here yesterday!