Fork repair discussion WideGlide

Stiction, other issues

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Excalibur
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Fork repair discussion WideGlide

#1

Post by Excalibur »

Got time to devote to fork issues, so I have them apart.

Main problems were too much stiction plus they are too firm.

Measured tubes at 27" long. Searching around I find OEM length 24.75" so mine are 2.25" over.

One spring is bent. Two of its' coils have rubbed.
f1.jpg
f2.jpg
f3.jpg
Questions:
Any thoughts how to check true and straightness? Forks slide OK each on their own.
Are any of the bits obviously repop?
Mounting bosses for fender are not equal, See last pic. Is that normal?
Any reason I can't or shouldn't cut and rethread tubes shorter or even to stock length? (Wheel is 19")
Could springs be FLH, so a bit too strong for my application?
What else is worth checking?

Resuming my study on the subject. Hoping to learn

Thanks.
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Mongrel505558
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Re: Fork repair discussion WideGlide

#2

Post by Mongrel505558 »

Excalibur wrote: Mon Sep 12, 2022 10:13 am Got time to devote to fork issues, so I have them apart.

Questions:
Any thoughts how to check true and straightness? Forks slide OK each on their own.
Are any of the bits obviously repop?
Mounting bosses for fender are not equal, See last pic. Is that normal?
Any reason I can't or shouldn't cut and rethread tubes shorter or even to stock length? (Wheel is 19")
Could springs be FLH, so a bit too strong for my application?
What else is worth checking?

Resuming my study on the subject. Hoping to learn

Thanks.
Roll them on a flat surface to check for true and straight (like rolling a cue over a pool table to check for straightness).

I would say get a new pair of tubes, but then I remembered where you're located and that it may not be so easy.

An alternative to replacing tubes: Progressive Suspension makes a spring kit for 41mm forks that are progressively wound and the length can be "tuned" by fitting PVC spacers you cut to fit to give you the desired ride height. I used them to lower a FXWG dual-disk front end I put on my pan when I finally decided I need brakes. Lowered it 2" and gives me a very good ride.

https://www.progressivesuspension.com/p ... wering-kit

For the fender mounting boss question, it looks like the one shown on the right has a more sweeping radius toward the mounting hole, if that's what you're talking about. I've never paid attention to this detail - I always thought they fender mounting bosses were symmetric between the two sides.
Raytag
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Re: Fork repair discussion WideGlide

#3

Post by Raytag »

Hi Ex,

for my 16" wheels I dug out some am tubes +2" shortened them and threadend them on the lathe
I was really surprised about how thick the chromelayer was.

To check the straightness I used the lathe too
I don`t have such large perfectly flat surfaces. And glass is by no means flat IMHO.

Without the tube I adjusted a diameter of the chuck jaws to ~41mm, wound some strong wire over the jaws (fabbed aluminium jaws)
and tightened the wire the hardest I could. Basically applying pressure onto the jaws. Then I bored those jaws to the dia of the tube accordingly.

With the tube loose in the chuck I was holding the threadend end of the tube (deburred) firmly onto the live center of the tail stock.
Turning the tail stock towards the chuck to my mark.
Still holding the tube onto the live center I tightened the chuck.
This way I`m avoiding that the tube cocks in the chuck while I`m tightening it

Putting a dial onto the tube revealed the chrom- or copperlayer not to be even ( I checked back and forth).

I cut and threatend them on the lathe as well.
My only parting tool is HSS ... so with a 160rpm and plenty oil I cut them to the desired length.
This creates a hell of a noise and I could hear that the chrom/copper layer wasn`t evenly spread which confirmed my meausserments before.
Then threadend them internally again.

I use standard 41mm seals from dirtbikes. All those James and whatever is total BS IMHO.

Each tube will slide easily by itself but bolted together they might cock.
My Hydra-Glide frontfender isn`t 100% straight. So just tightening the 4 bolts on the boss of each slider twists the whole fork just enough
to give me a bumpy ride when hitting small potholes
So I must use a sequence in tightening them.

I believe all those 41mm springs are the same. Just my opinion.

Ray

I put some pics of the process into my gallary but this PC doesn`t allow me to access my own gallery. The mod onće tried his best . maybe you can see those pics of shortening my tubes ?
LOL
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Last edited by Raytag on Tue Sep 13, 2022 7:38 am, edited 2 times in total.
Mongrel505558
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Re: Fork repair discussion WideGlide

#4

Post by Mongrel505558 »

The 41mm springs I'm talking about are progressively wound - unlike the factory-type springs in the picture. They will compress a certain distance from the bike's weight until the stiffer, heavier-rate portion of the springs kick in - thus lowering the stance of the bike while still providing a good ride. I love how they worked out on my pan. I've never bottomed these forks out with these springs and the handling is crisp.
panhead
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Re: Fork repair discussion WideGlide

#5

Post by panhead »

I put some pics of the process into my gallary but this PC doesn`t allow me to access my own gallery. The mod onće tried his best . maybe you can see those pics of shortening my tubes ?
LOL
Here is the link to your own gallery: https://www.hydra-glide.net/cpg/thumbnails.php?album=98
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Re: Fork repair discussion WideGlide

#6

Post by Raytag »

Jim,
what I`m saying is that I doubt that there is a difference between 41mm WideGlide Springs and 41mm full dresser springs
Springs from PS are different from OEM

PS
Thanks Panhead, I`m still encountering this weird problem that one browser can access my personal album and the other can`t (No permission). But we have been into this some years ago and it`s ok. No need wasting time on this again. Thanks again.
Mongrel505558
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Re: Fork repair discussion WideGlide

#7

Post by Mongrel505558 »

Raytag wrote: Tue Sep 13, 2022 7:51 am Jim,
what I`m saying is that I doubt that there is a difference between 41mm WideGlide Springs and 41mm full dresser springs
Springs from PS are different from OEM

PS
Thanks Panhead, I`m still encountering this weird problem that one browser can access my personal album and the other can`t (No permission). But we have been into this some years ago and it`s ok. No need wasting time on this again. Thanks again.
.

With regards to factory springs, I have some hanging around from both an FXWG and an FLH, and if there is a difference it definitely isn't visible. I was just suggesting the PS springs as an alternative to cutting and threading the tubes you have if your goal is to shorten the forks a bit. If you're proficient with a lathe then go for it.
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Re: Fork repair discussion WideGlide

#8

Post by Excalibur »

Thanks for super ideas. It helps a lot as I ponder the fix.

Rolling the tubes on a flat surface is a good idea. There's an old saw bench out back that could be big enough. Otherwise I pop them in the lathe.

Fender mounting lugs. There's 4 -5mm (0.160" -0.200") difference in height. Means fender mounts slightly to one side. Pictured:
hw1.jpg
I've run Progressive fork springs before so I know what they're like. What I like even more is the RaceTech valving. It's another step, a big one. What's nice is the ability to independently adjust high speed compression dampening. Kit pictured.
hw2.jpg
Looking at seal. They aren't leaking. Tube falls under its' own weight though there is some friction created by the seal-to-tube fit.
Ray, how are the dirtbike seals for friction?
hw3.jpg
Is this the expected fork tube? Commonly listed is a fork tube with a bushing on the lower end. 45417-80 is the part for '80 -'83 but could these tubes be over length FLH? e.g. 45825-77A
Often a merchant will show a stock/generic picture so gets confusing.
hw4.jpg
Plan: Assemble tubes and sliders in trees but without springs. Fit axle without wheel but with a spacer so it can be tightened up in situ. Test by raising/lowering sliders by hand. Work to eliminate stiction, then fit fender noting any extra stiction.

I have a nice pair of Pan FLH springs. These appear to be very close in diameter though an inch or so shorter. Any reason not to use assuming spring weight is suitable?

Thanks for any thoughts.
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Re: Fork repair discussion WideGlide

#9

Post by RooDog »

I have a nice pair of Pan FLH springs. These appear to be very close in diameter though an inch or so shorter. Any reason not to use assuming spring weight is suitable?

Thanks for any thoughts.
[/quote]

You may use any springs you want as long as they physically fit. Adjust the preload with spaces at the top to suit. This is called tuning.

Can you tell me more about the Race Tech valves? How does one adjust them once installed as these forks typically destroy the seals when the tubes & sliders are separated?
....RooDog....
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Re: Fork repair discussion WideGlide

#10

Post by nifty »

Excalibur wrote: Tue Sep 13, 2022 2:10 pm Thanks for super ideas. It helps a lot as I ponder the fix.

Rolling the tubes on a flat surface is a good idea. There's an old saw bench out back that could be big enough. Otherwise I pop them in the lathe.

Fender mounting lugs. There's 4 -5mm (0.160" -0.200") difference in height. Means fender mounts slightly to one side. Pictured:
hw1.jpg

I've run Progressive fork springs before so I know what they're like. What I like even more is the RaceTech valving. It's another step, a big one. What's nice is the ability to independently adjust high speed compression dampening. Kit pictured.
hw2.jpg

Looking at seal. They aren't leaking. Tube falls under its' own weight though there is some friction created by the seal-to-tube fit.
Ray, how are the dirtbike seals for friction?
hw3.jpg

Is this the expected fork tube? Commonly listed is a fork tube with a bushing on the lower end. 45417-80 is the part for '80 -'83 but could these tubes be over length FLH? e.g. 45825-77A
Often a merchant will show a stock/generic picture so gets confusing.
hw4.jpg

Plan: Assemble tubes and sliders in trees but without springs. Fit axle without wheel but with a spacer so it can be tightened up in situ. Test by raising/lowering sliders by hand. Work to eliminate stiction, then fit fender noting any extra stiction.

I have a nice pair of Pan FLH springs. These appear to be very close in diameter though an inch or so shorter. Any reason not to use assuming spring weight is suitable?

Thanks for any thoughts.
Exc
My 2c

TUBES:
41mm is a misnomer, All H-D wideglide tubes 1949 to at least 2017 are 1-5/8” = 1.625” = 41.27mm, all the Jap, German & Italian 41's appear to be dead on 41.00 mm.

1977-1983 approx Showa wide glides are fully sealed (no breathers) have no bushes, legs run straight on tubes, ala Ceriani, Meriden Triumph 71 up & most Jap & Euro forks pre mid 80’s. TSB 717 refers

1984-2017 approx Showa wide glides have bushes, OD of lower bush runs inside leg, ID of upper bush runs on tube, ala most Jap & Euro conventional forks of same era. Intent was to reduce “stiction”.

All telescopic forks work best with rake between 25 & 30 degrees, anything over 30 degrees dramatically increases friction & “stiction” and decreases ability of fork to properly function over uneven surfaces and respond to dynamic loads.

LOWER LEGS:
IMO you assume castings are symmetrical, for your perceived problem with fender/mudguard mounts you should be measuring from ID to faces.

DAMPING:
IMO the 84 up (and probably 77up) stock Showa dampers are quite good (way better than MoCo Hydraglide dampers), if stock Showa dampers are in good shape there is no need to go to gold valves. Gold valves can be fished out from top using a length of wire with hook for adjuster screw.

PRE-LOAD SPACERS:
I don't know about NZ, but in OZ, last time I looked, the as supplied by Progressive Susp US ¾” nom bore schedule 40 PVC pipe (20.6mm ID x 26.7mm OD) was hard/impossible to find.
A close equivalent is available in Oz and possibly NZ.
Black polypropylene irrigation stand pipe, comes in various shortish lengths, with threaded ends:
¾” nom bore = 20mm ID x 26.8mm OD, from pump & irrigation suppliers, polypropylene is softer than PVC, can use with washers against nut & spring.
Steel pipe is heavy, but light gauge 25mm square steel tube will fit inside WG tubes, possibly potential to rattle, can use with washers against nut & spring.
Aluminium wears & deposits metal in oil, use with washers against nut & spring.

Don't over-do the spacing, forks must have some static sag/droop with rider aboard.

SPRING RATES & OIL:
Longer forks obviously require longer pre-load spacers, not so obvious is the increased air volume and resulting lowered spring rate when changing to longer forks (air volume is effectively another spring, spacers must be hollow to allow filling with oil). This is why H-D spec more oil for the later longer fork models.

Within limits, for any given fork movement, the effective spring rate of fully sealed Showa fork may be “tuned” by varying the oil quantity (increasing oil volume decreases air volume, oil is not compressible, air is compressible, ergo less air available to compress, results in higher air pressure when fork compressed = increased effective spring loading.
However, insufficient oil will become aerated and damping will be affected, while excessive oil can drastically increase internal pressure (as can hydraulic lock)

Example late 1.625" Showa Oil Quantities

11.5 ..... 12.5 ..... FLST 1986-2006; FXST 2007-09

12.4 ..... 13.4 ..... FLST 2007-09 (approx 4" longer tubes compared to 49-76 Hyrdraglide)

13usfloz = 384.5ml/cc

Oil quantity must be sufficient to completely submerge damper valving, i.e. Gold Valves may require additional oil.

Ensure trees not tweaked, or all above a complete waste of time.
Ensure axle not inducing misalignment, ditto.

Meriden Triumph had a handy dandy fork alignment quick checking tool, but too narrow for WG and only good if stored and handled carefully. A piece of "plate" glass works well (not commercial window glass) some old time TV sets with flat glass in front of CRT were optically flat "plate" glass, or good glass suppliers will sell you some. Mk1 eyeball is better than nothing.

BTW, with the appropriate corresponding top plugs/nuts, 1984-2017 Showa 1.625" tubes. legs and attendant brakes will fit to 49-76 trees (inc adjustable and Servi-car), some applications may require custom axle. Your results may vary.


Nifty
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Last edited by nifty on Thu Sep 15, 2022 8:10 am, edited 8 times in total.
RooDog
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Re: Fork repair discussion WideGlide

#11

Post by RooDog »

I found that after the axle nut is tightened, the lower clamp should be loosened and the fork bounced a few times to center the axle in the clamp, and then tighten it.....
....RooDog...
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Re: Fork repair discussion WideGlide

#12

Post by Hogey »

Niffy your dead right finding the pvc spacer size in OZ. Also progresive springs are from memory Are 95lb. then go to 130lb as they get near 3/4 compression. Stock 65lb According to Race Tech. i tried the P S and found way to hard for our roads in my 71 FLH. i played with my 2001 FXST suspension fitting P S gas cartridges went on a 200k ride rough as hell. settled on stock springs and Penrite Syn 5wt fork oil. excellent now. Googled fork oil tests and the Viscosities are not what is marked on the bottle on them i think Lucas was near the Mark. I also have race tech gold valves in shed that i have not tried. Also set off nice 78 FLH springs. Should have added i set air Gap in bottomed out position. My 68 has 99 road king forks with twin discs yet to play with them.
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Re: Fork repair discussion WideGlide

#13

Post by Hogey »

Should have added i lowered forks by fitting a spacer under the rebound spring of the require length and if you have preload spacer remove the same amount that u fit under the rebound spring. Also Showa is marked on inside legs unless some one removed cast markings
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Re: Fork repair discussion WideGlide

#14

Post by Raytag »

Excalibur wrote: Tue Sep 13, 2022 2:10 pm ...
Ray, how are the dirtbike seals for friction?
...
Let`s say this way.
I`m still regreting every single mile for using am HD seals.
:evil:
I really do.

Bouncing with my shovel-chop (2"+ over) for a complete season thru europe.
Took the fork apart maybe 10 times, used different oils, got NOS dampers for a hell of a money ,changed 2 or 3 times the seals,
"naw yer ole adjustable triple tree isn`t straight" , naw yer 16" Ape and 4" riser amplifies it" ," naw the hardtail frame is crooked" ...
Just a few comments i had to listen to.

Jap seals for 10 bucks .
Whoaaa
OEM-Forks can really work :wink:
:lol:
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Re: Fork repair discussion WideGlide

#15

Post by nifty »

From my local Bearing shop I got some nice double seals, hadn't seen them before, not just a double lip, but a complete double seal, one piece, but opposed seal lips with their own garter springs, marked SOG 108770 41mm x 54mm x 11mm, for OZ dwellers the CBC Bearings number is RSM04105411LAN. work best under 45420-80 FXWG type boots with a little grease inside. With bare tin covers top garter spring exposed to water, can re-machine the late Touring legs to accept 45420-80 and run the boots under the tins. These double seals fit 84up legs, one each side, I don't know dimensions of L77-83 seals.
Seals for 49-E77 readily available from industrial suppliers.
AM wire retainers for late models come in a 10pack for less than $20usd and fit back to 49.

Nifty
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