Forking around with Lucille

Time for a fork oil thread? :smoke: Feels good when it's done huh? I'd much rather do fun things instead of forks, like changing the rear tire on a full dress GoldWing. The tire is off. I really enjoy the tire and rim part, assembly aint too bad either, Stripping the bike is the part I don't care for. Ah, and I get to use a few "special" tools.

Scott
 
I'd rather have my head stapled to the floor than change a tire on a big heavy bike. You're a brave guy Scott.

Fork oil thread....thank you, but no.

Grizld1 - good for you. But with the greatest respect, I'll bet you haven't had one as f-ed up as Lucille's left hand leg seal pocket. It looked like somebody had removed the last seal with a hatchet and 7 or 8 double scotches. It took 15 minutes with a die-grinder to get it reasonably presentable. Getting the new seal back in was...a battle...until I used my new tool.

Anyhow we're all done and nothing is leaking so I'm happy.
 
You're a braver man than I, Pete. I wouldn't even try to rehabilitate a slider that's been butchered that badly. Congrats on your success.
 
Well, lets see how she stands up. I did a 20 mile ride yesterday with no signs of distress and outwardly, it looks fine. I think as long as the seal stays put - and it should because of the back-up ring and spring clip - she should be OK.

I also replaced the fork legs - so all is well there.

Anyhow - I am doing the write up now.

Pete
 
OK - so I spent about 2 hours today writing this up complete with photos etc and then the forum gave me an error message about posting less than 10,000 characters. Shoot - that was frustrating.

Anyhow, I managed to save my work as a Word file and have asked the moderators for next steps. I'll get the article up as soon I get their answer.

Pete
 
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Just split your write-up into several posts, that's all. Then you won't run into the size limit thing.
 
Yeah - I'll do that. Sure made my heart jump when it gave me the error message.
 
PART I
1976 XS650C 34mm dia. Fork Seal Repair & Fork Tube Change

APPLICATIONS
: This note applies to 1976 C-model XS650C bikes and may be applicable to earlier models. Later 1977-on bikes have 35mm dia. forks and while the principles are the same, many details of the task will differ including the special tools needed to do the job.

TIME REQUIRED: While it looks like a big job, this really isn't too bad. None of the parts are heavy or hot and nothing should be done up too tight. However, some special tools are very helpful (see the text below plus my separate post on the 34mm Fork Damper Rod Holding Tool. I would estimate that the first time you do this - it could easily take a day - assuming you have everything ready to go. The second time, it would take perhaps 3-4 hours and once the fork legs are out of the bike, perhaps two hours or less to do both legs.
This is the first time I have ever been inside the forks of a motorcycle - and it took me a week because I had to make a couple of tools and I had a business trip to Ottawa in the middle of the week (800 km away). Oh well.

TOOLS: Here is a reasonably complete list of the tools you will need besides the usual metric sockets and wrenches, pliers, cutters etc.:
  • shop manual (I have a Haynes, a Clymer and the one on the web which everyone downloads and uses) - all are useful;
  • a jack stand to prop up the front engine mount of the bike;
  • an 8mm Allen key - long - to deal with the lower bolt in each fork leg;
  • torque wrenches for critical fasteners;
  • 17mm fork cap tool (really you could simply cut a 4" long piece off a 17mm Allen key - or buy the tool from MikesXS); I was extraordinarily fortunate that Coconut Pete had an extra MikesXS tool and gave it to me - thanks Pete!!
  • small sharp "pick" to fish the spring circlip out of the seal pocket;
  • some sort of tool to keep the damper rod from turning when you are loosening / tightening the lower bolt (see below for details);
  • a means of removing the old fork seal - I strongly recommend using a small tire iron / spoon with a nicely rounded end - as suggested by Gary;
  • a means of installing a new seal - either a proper motorcycle fork seal installation tool/slide hammer - or a piece of 3/8 threaded rod, 18" long and some nuts and washers;
PRELIMINARY TASKS:
  1. Put the bike on the centrestand and put a sturdy support under the front engine mount so that the front wheel is off the ground. A good idea might be to lash the bike to the ceiling of the garage to ensure that it cannot tip off the stand - as has happened here or there to some folks...:cussing: ....dammit.
  2. Remove the front brake caliper and secure it to the frame of the bike with a zip-tie (do NOT allow the caliper to simply hang on the hose).
  3. Remove the fender and the cotter pin & front wheel - and keep dirt and debris out of the wheel bearings/axle and speedo drive unit. Set everything aside in mechanical system groupings to assist with reassembly (I used several of those magnetic bottom bowls from Harbor Freight/Princess Auto). Do not set the cotter pin aside - throw it away because you WILL be using a new one - won't you!
  4. Remove the handlebar and secure it to the bike (somehow) so that it doesn't flop around and bash up your fuel tank.
Caliper_Secured.jpg
IMPORTANT:
loosen the TOP pinch bolt - ONLY - this make it much easier to loosen the fork cap. Leave the two lower pinch bolts tight for now. This was an important suggestion from Gary - and he's dead right about it.

Use the 17mm Allen key tool/piece to loosen (but NOT remove) the top cap of the fork. DO NOT remove the cap all the way - unless you are just going to change the fork oil. Simply loosen the cap half a turn or so.

NOTE: do this BEFORE loosening the lower fork leg pinch bolts. The fork cap is not very tight but it is much easier to remove and install it with the leg mounted in the bike and secured to the triple-tree by the lower pinch bolts.
Fork_Cap_Tool-2.jpg
Now you can loosen the lower pinch bolts on ONE of the fork legs and slide the leg down out of the triple-tree clamps. The leg should slide out quite easily but if not, a little gentle persuasion with a soft mallet on the top of the fork leg may be needed.

DO NOT hammer on the soft aluminium fork tube cap and do NOT use any lubricant if you can avoid it. You want the interface between the fork tube and the triple-tree clamp to be dry so that it will be secure after reassembly.

FORK LEGS - Disassembly
Mount the leg in a vise using one of the brake caliper mounting bosses (NOT the tube itself of course!! :yikes:) - and be sure to use a piece of wood or aluminium jaw covers on your vise jaws to protect the fork. The aluminium of the lower slider is quite soft (as we shall soon see....:().

At this point - you can either use an air or electric impact gun (rattle gun) to remove the lower bolt that secures the damper-rod to the fork lower slider - OR - you can use some sort of damper rod "holding tool" to prevent the rod from rotating while you use an 8mm Allen key to loosen the bolt.

I used both methods (rattle gun on the LH leg and the Allen key & damper rod holding tool on the RH leg). I like the "tool" method better because it is gentler on these important components - and I do NOT want to have to find them on-line if I mess them up. Having said that, the rattle gun method worked fine - but you need to leave the spring and fork cap in place before using the gun - otherwise, the damper rod will simply spin and the bolt will not loosen-up.

Whatever method you use, now remove the fork cap all the way (it will pop-up a little bit when you release it from the threads) and then lift out the top-hat shaped spring seat which looks like a little washer - but it is a special hardened part, (so DON'T friggin' lose it). There may also be a tubular steel spacer ("distance tube" in my Haynes manual) - remove it and set it aside.

Slide the spring out of the fork and have a cloth ready - there will be a fair bit of oil dripping off the spring which will get all over your shorts (and again, please don't ask how I found this out).
You can now fully drain the fork leg. Everyone makes a big deal about how bad the oil smells - but I didn't find it too noxious. I was a bit surprised at how little oil came out though: I guess the rest of it was all over the front end of the bike....and my clothing... :sick:.

NOTES:
  • when you remove the lower fork bolt and the little drain plug screw - do NOT lose the copper crush washer on the bolt or the little fibre washer on the screw. The crush washers are cheap - but I don't see anyone selling the fibre washers.
  • Also - if you pump the fork tube up and down, oil will come squirting out of the little hole sideways across your workbench and all over your shirt (and once again, please don't ask me how I discovered this :rolleyes::oops:).
LH_leg_drain.jpg

Drain_Plug&Fibre_Washer.jpg


Here is a photo of my super-duper 34mm Fork Damper Rod Holding Tool being used to hold the damper rod while I loosen the bottom bolt on the RH fork leg with an 8mm Allen key. The tool works perfectly. I will post a separate note on making the tool with the required dimensions after I complete this note.
RH_Leg_DISassembly_w-Tool.jpg
A photo of how my damper rod holding tool engages the top flats of the head of the rod is below. Many people simply squash a piece of tubing down to a 10mm wide oval shape - and that should also work because the damper rod-lower fork bolt joint shouldn't be too tight.

FYI - the slot in the end of the damper rod holding tool is 10.2 mm wide x 10 mm deep.

Damper_Rod_Tool-engagement.jpg

NOTE
: later 1977 forks use a totally different damper rod end and so this holding tool will NOT work on them.
 
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PART II
FORK TUBE REMOVAL
Now that the leg is drained and the damper rod bolt out - carefully slide the fork tube up out of the lower slider and remove the damper rod from the tube. It should simply slide out when you invert the tube - but DO NOT let it hit the floor.
LH_Leg_Damper-Rod.jpg
Make note of how all the parts fit together - and then set the tube and damper rod parts aside.

If your tubes are pitted like Lucille's, they are basically scrap - unless you can get them re-plated with hard chrome. I looked into this - but it wasn't easy to find a supplier and XS650 Direct (MikesXS) sells fork tubes for $180 CDN. I checked them out at the warehouse and the tubes appear to be identical to the stock OEM tubes removed from Lucille - so I bought them and they're fine. Here is a photo of a pitted fork tube which, I am sure was one of the reasons why my fork seals got chewed up.
Pitted_Fork_Tube.jpg
Once the fork tube is out - you can see the fork seal down in a pocket in the top of the lower fork slider. It is under a thin steel back-up washer (its called a "guide" in Fig. 4-2 of my Haynes manual - page 89) which is retained by a wire spring circlip.
Spring_Clip_Removal-2.jpg
Back-up_Ring_Removal.jpg
NOTE: BOTH the circlip and the back-up ring MUST be removed before attempting to remove the fork seal itself.

FORK SEALS - Preliminary Steps - DO NOT OMIT
Remove the little spring circlip and back-up washer with a little pick tool as shown in the photos above - and DO NOT scratch anything with the pick.

Invert the fork tube and remove the little alloy damper rod seat which will still be down in there. Be sure to make note of how that little seat comes out - NOTE that it is tapered toward the top as shown in the assembly photo below.
LH_Leg_Damper-Rod.jpg
Set those parts aside and again - BE SURE to note how they went in and keep them clean!

SEAL REMOVAL & CLEANING - the good, the bad and the ugly...
  • NOTE: do NOT try to remove a fork seal until you have removed the spring circlip AND the thin steel back-up ring/washer!!
Now comes the really fun part! You need to remove the old seal, which should not be too hard, but you may run into some difficulty (I sure did). I tried a method suggested by our very own Baron of Baraboo - Gary - on the Forum. He suggested using a tire lever/spoon mounted in a vise. This method worked fine for the RH leg (which I did after the LH leg) but the LH leg seal would not budge - so I had to resort to a seal puller (see photo). Some folks have actually cut the seal out with a Dremel tool and a cutting wheel - and that was next on my list (but NOT recommended).

The Good - Gary's Method of Fork Seal Removal
I found that Gary's method of mounting a tire spoon in a vise and using the nicely rounded end of the spoon to pop the old seal out worked absolutely great on Lucille's RH fork leg (see photo below). He also suggested mounting the spoon low in the vise and using a piece of aluminium as a fulcrum across the end of the fork tube to protect it from being dented by the hard steel tire spoon.

I was surprised to find grease in under the dust boot on top of the spring clip and back-up washer on the RH leg. There had been NO grease at all in the LH leg - so somebody had definitely been into the forks on this bike before, and after they f@cked up the LH leg, they tried something different on the RH leg.
RH_Leg_Grease_Seal_Pocket.jpg
Seal_Removal-Garys_Method_Tire_Spoon.jpg

The BAD & UGLY - a Harbor Fright - Princess Auto Seal Remover Tool

I DO NOT recommend using one of these nasty metal-eating seal puller/remover tools on soft aluminium parts like fork sliders - it is just too easy to scratch the he!! out of the seal pocket - as had been done very thoroughly by my PO on Lucille's LH leg. The inside of the LH leg seal pocket had several very deep gouges and the burred material had been left in there :wtf: - from a previous seal change which is why the old seal would not come out with a normal level of effort. Holy cow - what a pain!
Seal_Puller-BAD-2.jpg

Anyhow, I finally got the old seal out using a seal puller - VERY carefully - and then I polished-out the gouges as best I could with a fine stone and a die-grinder plus some 400 & 1000 grit emory cloth which came out OK. Fortunately, none of the gouges went all the way from the bottom of the pocket to the top edge and so I wasn't too worried about the oil leaking past the new seal - but I was concerned about installing the new seal on the somewhat rough inside surface of the pocket. I didn't want to polish it too much for fear of increasing the diameter excessively and winding up with a loose seal and a leaky leg.

Once you have the seal out of the leg - clean everything thoroughly using brake cleaner and clean rags. It actually wasn't too big a job, but I did go through an entire can of brake cleaner on the two legs and stank up the Disaster Central Workshop for a little while. The fumes sort of took me back to the mid-70's...:confused:

RE-ASSEMBLY
NOTE:
I searched the XS650 Forum for advice on fork seals and one persistent question is - which way does the seal go in? Well, boys & girls, it goes back in exactly the same way it came out - assuming the last person did it right. Just to be sure though, here is the correct way:
  • look at the new seal;
  • see the coil spring up inside it?
  • that spring side faces DOWN into the fork seal pocket and the side with the printing faces up.
Now, here we come to a fork (get it?? ;)) in the road. There are two ways to proceed when installing the new fork seals and re-assembling the forks:
  1. put the fork tube into the lower slider and install the new seals using some sort of seal driver. Bike shops/on-line sellers market these in various ID sizes to suit different bikes. The installer is used like a slide hammer over top of the upper fork tube BUT you need to be careful to NOT scratch up the outside of your nice new fork tube when driving the new seal back into place.
  2. you can leave the fork tube out and pull the seal into place in the lower fork slider using a piece of threaded rod and some suitable washers and back-up plates. Simply grease the seal and pocket, and screw the seal in till it seats in the seal pocket in the lower fork slider.
The key issue is to NOT get the seal cocked in the seal pocket. That could damage the seal and/or the lower fork slider. Also - when driving the seal into place - don't go Neanderthal and risk cracking the slider (as at least one XS650 Forum member has done recently). Some people advocate using a suitably sized socket as a driver - but the risk of getting the seal cocked in the pocket is much too high in my view (my hands and eyes just don't work that well together, I guess).

On Lucille's LH (i.e. damaged) leg, I borrowed a proper tool from a buddy and tried the slide hammer method - but the seal still got stuck (it was straight, but it simply would not move down into the pocket likely due to the roughness from the prior damage). Soooo, I used a piece of 3/8" dia. threaded rod and some suitable nuts and washers etc. - and pulled the seal down the rest of the way (see photos). In the end, it worked out just fine.
Seal_Install_Tool-1.jpg

Seal_Install_Tool-2.jpg


I found that on the undamaged RH leg, I could literally push the seal nearly halfway in by hand - (photo) - but then I needed to use the threaded rod to gently pull it down the rest of the way.
Seal_Push-in_by_Hand.jpg

You will know that you have the seal fully seated when:
a) turning the threaded rod nuts or driving it with the slide hammer tool gets really hard, and
b) the slot for the spring clip is fully exposed at the top of the fork slider tube.
If you cannot fit the back-up ring and the circlip - you need to pull the seal down a little bit further into the pocket. Don't overdo it though.

My overall assessment is that the threaded rod method is superior and safer on old, slightly fragile, hard-to-replace components - and that is how I will do it in the future. The components for using this method are cheap and simple and easy to find plus you can go slowly and not risk damaging anything.

FORK TUBE & DAMPER ROD INSERTION
GRIZLD1 & GARY
: this is where I simply forgot to measure the danged damper rod holes - sorry about that! I took some photos of the rod and holes but got a phone call in the middle of the job and muffed the next step which was to make those measurements.

Now pour some fork oil down the inside of the fork tube and then put some more oil on the top piston of the damper rod and that assembly down into the fork tube until it pokes out the end of the tube. Then slip the little alloy damper rod seat (that tapered thingy) onto the bottom end of the damper rod and push it back up into its little pocket in the fork tube until the bolt seat is flush with the end of the fork tube. The oil you put on the seat will help stick it into place.
Damper_Rod-34mm.jpg
Damper_Rod_Head-34mm.jpg
LH_Leg_Damper-Rod.jpg
 

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PART III

Now that you have the damper rod down in the fork tube and seal installed in the lower slider, simply put some clean fork oil on the inner lips of the seal and on the OD of the fork tube and gently slip the fork tube-damper rod assembly into the seal. I found that putting the tube into the seal at an angle to "start" the engagement worked well - then straighten it up and slide the tube gently down into the fork slider. Push the tube down until it bottoms in the slider.

For this task it is helpful to clamp the fork leg almost horizontally in the vise so that things don't fall apart as they travel down the inside of the fork tube (see the photo).
View attachment 101913
When tightening that lower bolt - use a torque wrench and set it for 14 ft-lb. You need a fairly long 8mm Allen key for the RH leg where you need to go through the axle hole in the bottom slider.

DO NOT
go with the manual and tighten to 40+ ft lb. Also - don't forget to install a new copper crush washer on the bolt - and be sure to replace the little drain screw with its fibre washer in the side of the lower fork slider.

At this point, install the dust boots/seals/wipers. This is an easy "no-tools" task that takes about two minutes. I found that the new dust boots from XS650 Direct were very tight - but they fit well and do the job. From the photo - you can clearly see how tight the fit will be on these puppies - but they are quite flexible and I was able to install them by hand..
New_Dust_Cover-TIGHT.jpg

SPRINGS & THINGS
Now you can simply slide the new spring into the fork tube - BE SURE to place the tighter wound spring coils toward the top of the tube - if you have a progressively wound spring. Those closer coils essentially replace that "distance tube" spacer component which you may have removed with the old spring. They make the fork stiffer as it reaches the upper limits of its travel - a better set-up than the original evenly spaced coils and spacer tube, in my view.

I also found that the new progressively wound springs were significantly different from my old OEM linear wound (i.e. uniformly spaced coils) springs. At least I presume they were OEM parts that I removed. The old springs had sagged A LOT over 41 years since MamaYama installed them and they were appreciably softer than the new springs. I didn't measure the actual spring rate of the old springs, but I would say that they were at best, 75% of the new ones, in terms of axial stiffness.
Spring_Comparo.jpg
Apparently, the free-length of a stock spring is supposed to be around 18.5-19" - and there was a spacer installed above the spring - but the old springs I removed from Lucille's forks were fully 1.25" shorter than stock (they were only 17.75" long as you can see in the photo). Here is the data, plus see the photos below and note the steel spacer which mounts inside the fork tube under the top cap in the original spring set-up (NOTE: all measurements are approximate using a tape measure):
  • Stock OEM spring free length : 18-1/2 - 19"
  • OLD springs rem. from forks (2017): 17-3/4"
  • Stock spacer (aka "Distance Tube"): 2-3/8"
  • NEW progressively wound springs: 19-5/8"
Basically, I found that due to the much stiffer new spring, there was NO WAY I could get that new spring into the fork with the spacer (distance tube) - so I simply left the spacer out. The total length of the old spring plus that spacer was nearly the same as the new spring - and as noted, the new spring is much stiffer than the old linear wound unit.

Once you have the new spring installed, pull the inner fork tube "up" and your fork should look like the photo below.
RH_Leg_Assembled-NO-OIL.jpg
Finally, you will add the fork oil. We could get into a huge long "oil" debate here:hellno: - but I hate that sort of thing and so here is what I noted from my research on forks and fork oil:
  • the XS650 forks are felt to be under-damped (too bouncy) and under-sprung (too soft);
  • many people have added more oil and thicker (more viscous) oil to the forks;
  • some people have modified their damper rods (the Minton Mods) - but there is little or no data on doing this to 34mm forks from what I can tell. All of that work appeared to be on later 35mm forks which are a different design.
So - taking all of that into account, plus the fact that I am...ahem...perhaps, not as svelte as I once was...I made some choices - and I will live with them for now. The under-sprung issue is looked after by the new stiffer spring. The manual suggests 155cc of either 10W30 motor oil or simple 10W fork oil - and so I poured 160cc of 20W Lucas fork oil into my forks to increase the damping coefficient.

My initial riding shows that this works well: the bike feels much steadier and corners better with no bobbing and weaving. I am happy and if I want to change the oil later - that would be a simple 30-60 minute job.

Once the fork oil is in place (I used a kitchen measuring cup - but do not tell Mrs. MaxPete ;)), you set that spring seat / top hat looking washer on the top of the spring (with the little protruding part facing down into the spring) and then push down on the spring with the fork cap while turning the fork tube until the threads in the cap start to engage. I would keep screwing the cap in by hand until you cannot turn it anymore - and then finish tightening the fork cap once the legs are back on the bike and you can secure them with the lower (ONLY) triple-tree pinch bolts.

NOTE: I suggest doing this "by-hand" so that if you get it started cross-threaded, you don't power-on and wreck the components.
 
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PART IV
FINAL ASSEMBLY
Now - it is time to slip those snazzy new fork legs back into place on the bike. The left hand one went in easy as pie but the right hand one took a little "body English" on my part, plus some assistance from my good-guy neighbour, Roger, who came over to steady the bike and quaff a cool one with me. One little trick is that you may need to gently pry open one or more of the pinch bolt points with a flat screwdriver to enable the fork leg to go in.

Be sure to clean the insides of the triple-tree clamps but DO NOT use any oil or other lubricant - the whole idea is that these fork leg thingys stay put once they are mounted on the bike!

Once you have the legs in place, set them at the same height (mine simply lined up so that the top of the fork tube was flush with the top of the upper triple-tree clamp). Now,
  1. tighten the lower two pinch bolts;
  2. then tighten the fork cap with your 17mm fork cap tool;
  3. and THEN tighten the top pinch bolt on each leg to the required torque.
The idea of that sequence is that the upper pinch bolt may squeeze the fork tube enough to adversely affect the tightening of the fork cap - and that is not good. Once all three pinch bolts are tight - you're nearly done. NOTE: the fork cap does not need to be too tight - but be sure that the o-ring is seated and sealing.

Now, wrestle the front wheel (use a NEW cotter pin - PLEASE!!) and brake caliper into place, re-mount the handlebars - torque everything down and check the function of the front brake.

You should be good for a test ride!

Just look at the beautiful old Lucille - with those snazzy new legs!
Lucille - Ready_to_Ride.jpg
As noted earlier - she now rides really well - quite steady in the corners with not too much dive on braking and no bobbing and weaving over potholes.

She feels like a whole new bike - and I am delighted with the entire job.

In closing, I want to thank everyone who offered encouragement and suggestions for this job - and particularly Bruce (our local carb guru) who did most of the work on the super-duper 34mm Fork Damper Rod Holding Tool.

Cheers,

Pete

PS - I will post this now - and then re-visit it if me or anyone else notes any errors. If you do see a mistake or need a clarification - please PM me and I will try to respond as quickly as possible.
 
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SPECIAL TOOL - 34mm Fork Damper Rod Holding Tool

The top of the fork damper rod on the 1976 XS650C - and possibly some earlier models (GURUS please advise) is approx. a 24mm diameter cylindrical shape with two flats milled into the sides that create a 10mm wide x 8mm high register. This register can be engaged by a suitably shaped tool to hold the damper rod and prevent it from turning while loosening or tightening the bottom bolt of the fork leg.

Damper_Rod_Head-34mm.jpg


This note shows the fabrication of such a tool and provides the details of the slot that engages the top of the damper rod head.

I want to acknowledge the great assistance of our resident carb guru, machinist, welder and all around great guy - Bruce Durfy - did most of the fabrication on the tool.

BTW - Bruce is an accomplished flat-track racer (Veteran Class riding XS650 and XT500 bikes). Also, together with his pal Duck, who is from London, ON - they hold the 2016 US AMA National Sidecar Ice-Racing title. This pair of unknown Canadians won the title in a very strong field last winter on some god-forsaken frozen lake in Michigan. Their bike is a heavily modified XS650 rig and Bruce was the "monkey" on the hack while Duck was the rider. I guess it was a hell of a show!

DIMENSIONS:
  • the overall length of the tool should be approx. 17-18" for it to function properly.
  • the slot in the end should be about 10.2mm wide x 10mm deep to properly engage the register in the head of the damper rod.
  • the maximum diameter of the tool cannot exceed 23mm for it to fit down into the inside of the fork tube.
  • The surfaces of the tool must be smooth and free of burrs and any swarf (metal chips) must be removed prior to use - so as to not damage the inside of the fork tubes.
MATERIAL: The material is not critical but mine was made out of a 1" dia. bar of cold-rolled steel turned down to 23mm dia. Aluminium would also be OK, but it is harder to weld if that is a consideration.

FABRICATION
A slot was milled perpendicular to the long axis of the bar as shown in the photos below.
34mm_DR_Tool-Milling_Slot.jpg


After the slot was milled, an old discarded Allen key socket was welded to the opposite end of the bar to facilitate attaching a locking socket extension to the tool.

DR_Tool_Assy.jpg
Welding_DR_Tool.jpg


Once the fabrication is completed, it is ESSENTIAL that the tool be perfectly clean and free of any burrs or chips from the machining operations. We used a wire wheel on it and then a thorough wiping down with brake cleaner to ensure that the tool was clean and would not scratch the inside of the fork tube. This is critical because the damper rod piston seal runs on that inside surface and must seal properly to provide effective damping.

The tool - together with its locking socket extension is shown in the photos below. Also shown is a photo of the tool engaged with the head of the damper rod itself.

NOTE: Using an extension that is able to be locked into the female socket which is welded onto the top end of the damper rod tool is a very worthwhile feature.
Fork_Holding_Tool-1.jpg
Fork_Holding_Tool-2.jpg


Damper_Rod_Tool-engagement.jpg
 
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Max Pete, if you are working on the XS Special (35mm forks) then make something similar to geedubya above, but instead of flattening the end just weld on a metric nut measuring 17mm across the flats i.e. the nut from a 10mm threaded bolt. My piece of pipe was 600mm long and that was a bit on the long side. Of course I am assuming you have bought that MIG welder now?? The nut does not take much force so just tack it in a couple of spots. In the fork there is a bolt with a socket shaped head and the nut fits into it.

Edit: Something strange going on. Thread only partially loaded and now I see there are another 2 pages of entries and Max Pete has a TIG - well access to one.
 
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Wow Pete, quite the novella. An excellent, well written and photographed step by step of the entire process. Probably took you as long to put the thread together as to do the job. Excellent work and a great addition to the site Professor Pete.
 
Thanks Paul - that one will be a fair bit simpler than the '76 tool.

....and yes, the write-up took a while Bob & Robin. The fact is, I've never worked on motorcycle forks before and I suspect that there a lot of folks out there who also have not done these tasks, so I wanted to write a good "how to" for them.

Pete
 
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Thanks 2M - means a lot coming from you. In fact, I've already gotten a couple of important corrections from Gary - so if anyone wants to use the article as a guide, please wait a day till I can get it sorted out.

Cheers,

Peter
 
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