Suspension Mods Gen1

Sorry...the forks didn't arrive today. Hopefully tomorrow. Instead I was busy with experimenting.
A fork spring tester is "somehow" in the build:
20181011_191747dkdrz.jpg


And I am experimenting with solvent in a glass in an ultrasonic bath:
20181011_211455scdln.jpg
 
I have a pair of '99 forks not being used at present, my '99 has '04 forks on at the mo'. . . . you've got me thinking . . I may just strip them and have a poke around at the cartridge, see if I can disassemble it and clean it up. Then, if you are willing to share your info on your mods, I could also do some work on improving the operation of the cartridge.
Or will I need special tools to strip the cartridge?
I have already made a tool to get the fork cap, spring, and cartridge piston rod separated so am quite prepared to make new tools if I need to, lol.
Any help is much appreciated, I have little experience in this level of suspension work.
 
I am really happy because I was able to animate people to improve their suspension.
Disassembly and cleaning is a good first step.

Imho you do not need special tools, but I recomment the following:
- 29mm shaft holder
- 18mm open end wrench
- propane torch
- Cartridge "crown" tool
- loctite

My advice is to study the racetech videos on youtube prior disassembling the pistons/assembly.

In regards to the pistons...you need a flat surface, sandpaper and a dremel.

The rebuild is focussed 5W Maxima Fork Fluid. But I have to finalize a rebound stack and a compression stack. Or as another option a rebound stack in combination with a gold valve.
Based on the orifices in the hydraulic pistons a fork fluid with more then 18CST@40°C is not an Option anyway
 
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The last few days I was thinking and calculating right around the Busa-Fork.
The big topic is the harshness of the oem compression piston. because the bores are too small and the 12.5mm Rod is too big. However...there are also some good news. The Compression piston has "potholes" around the bores. This ensures a big and even contactpatch to the 22mm face shim.
Finally there is the option to drill the 4 holes to at least 3mm in diameter and use a dremel-tool to make several flow optimizations.
Finally you have to run a custom shim stack...job done...not a lot to do right?
 
Where did you get the Shock spring changing tool? That looks like Ohlins or Andreani? I am looking for one!
 
Where did you get the Shock spring changing tool? That looks like Ohlins or Andreani? I am looking for one!
This one is build by my father and me!

I started rebuilding the OEM Piston. Mod is on the left. Stock is on the right:
20181015_1149004deuq.jpg


20181015_114913ltcs6.jpg


To be fair. My dremel tool needs a new tip. this is the reason it looks a bit "wild". next one will be more beautiful.


I was able to build a new Stack based on some 25mm Cartridge Data and I think it will perform perfect from the start!

PN me if you want this mod.
 
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Alright...I started with the 99 forks:

Inner Assembly has to come out:
View attachment 1586332

New Spring and Preload Stuff + Cartridge + fork cap
View attachment 1586333

After Ultrasonic Cleaning:
View attachment 1586334

Entire Hydraulic:
View attachment 1586335
I love your compression tool for the fork spring. I don’t do suspension often, so I went the cheap “backyard mechanic” route and spent $10 dollars at the hardware store to use ratchet straps and the contraption below. I just run the strap through the axle hole at bottom of the fork and then put each hook at the of strap on each bolt and was the ratcheting system to compress the spring. Not my idea, just something I found on the internet.......
EEBDAB5C-3B09-4354-BE04-AAC7831B7907.jpeg

0A66C3DB-B8A4-46FD-8E3A-B2EF55A9A5E0.jpeg


C77D47F0-EABC-44A8-A579-A1E5B94123AE.jpeg


DB136D46-0B28-4E57-B83D-29BE533D5E65.jpeg
 
So....things are going on.
I was thinking a lot about where to go with the shock of the bike. Buy ohlins or take a gen2 shock or gen2 plus revalve by k-tech or racetech.

Luckily I found a shock in italy. It was unnamed but my professional eye recognized that it is a WP 46mm Shock. A shock that I know very well and bring to performance easily. So I bought it. 32$ incl. shipping.
This is the moment where you might get shocked:
img-20181112-wa00046sdvn.jpg


Alright. Based on the pictures on eb*y I know that the spring has to go. I was absolutely fine with that and I will order a spring with 140N/mm (@8-10mm preload) later from eibach.
There is no change to bring this spring with powder coating and treatment back to live. "Switch it" I said to myself.
The new eibach Spring will be around 65$ incl. Shipping.
The good news is...whatever is in a bad condition in this shock could be replaced. I can order it from WP Suspension.
So I started disassembling. After a few minutes I ran into the problem that it was not possible to unscrew the "seal head". It take a lot of effort, heat and some ideas to brake it loose....but finally:
img-20181114-wa000182cbi.jpg


Alright...Now comes the fun part. Taking everything apart:
20181114_144534cvf3b.jpg


The condition of the inner parts is really good and I was damn suprised about that. But the shock was build in 2001. So I will replace a lot of stuff anyway. At the moment I am ultrasonic cleaning a lot of parts and then I will inspect them so that I could make a list of replacement parts.
I have to check internal valving for the spec and I quiet surely will revalve the shock because it is always an easy job on WP-Shocks of this type. I was also thinking about replaving the valving assembly with racetech but I know a friend who is building his own 46mm and 50mm piston. I will try them in spring 2019.

Stay tuned for more!!!
 
I finally managed to get the parts I needed to rebuild the shock.
I cleaned all the parts and change the o-Rings, Piston Ring and some worn shims. Also I made a little revalve:
20181117_182507raceo.jpg


It is now time to rebuild and fill with oil and bleed and finallly add nitrogen to the shock.
The Spring didnt arrived so far...but that is just a minor problem
 
I finally managed to get the parts I needed to rebuild the shock.
I cleaned all the parts and change the o-Rings, Piston Ring and some worn shims. Also I made a little revalve:
View attachment 1588810

It is now time to rebuild and fill with oil and bleed and finallly add nitrogen to the shock.
The Spring didnt arrived so far...but that is just a minor problem
I finally managed to get the parts I needed to rebuild the shock.
I cleaned all the parts and change the o-Rings, Piston Ring and some worn shims. Also I made a little revalve:
View attachment 1588810

It is now time to rebuild and fill with oil and bleed and finallly add nitrogen to the shock.
The Spring didnt arrived so far...but that is just a minor problem
Hi. Very good post. I use a Penske rear shock set up for my weight. I have a Titanium spring also for my weight. I do LSR and drag racing.
 
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