Vintage Fox Factory Superbike Shox vs Marzocchi vs new Hagon 2810 or YSS Z-362

[Chuck78]

I am looking for some new rear shocks at some point, and I have ran across some used vintage high performance aftermarket shocks. The first choice (lower photo of similar shocks) is a set of Fox shocks that are referred to as Fox Factory Shox, and were looked upon as the best street and MX shocks ever made at their introduction in 1979. Eddie Lawson (and Wes Cooley?) both ran these shocks up until the changeover to monoshocks on serious performance bikes in 1983-ish. If found the manual herehttp://service.foxracingshox.com/powersports/Content/Resources/pdf/Vintage/FOX%20FACTORY%20SHOXforMX.pdf shows a pretty complex dampening system. Not quite as complex as the Fox is the Marzocchi Strada - this is the correct Marzocchi manual http://www.ducatimeccanica.com/marzocchi2.html
Racetech rebuilds shocks also, specifically vintage Ohlins, Fox, and Penske, as does Thor Lawson at Evolution Suspension and LE Suspension I believe it is, and most sell parts for several models of vintage shocks.

That being said, I am wondering how the Fox Factory Shox and Marzocchi Strada shocks will compare to new non-external reservoir Hagon 2810 shocks (6 position adjustable rebound dampening for $300, non-rebuildable) or YSS Z-series (gas charged, 60 position adjustable dampening, adjustable ride height, adjustable pre-load, $460). The external reservoir setup does give the bike an awesome look, but I wonder if the newer shock valving technology will be a whole lot better? Also, I have no clue what spring rates I am getting when I get these used vintage shocks. I had used a spring rate calculator before based on wire diameter, coil diameter, and number of coils, and found it to be very accurate, but its a bit of a gamble still.

I have built my GS750 up with chopped fork springs, 15w oil and cartridge emulators, fork brace, gs1100e alloy swingarm, 3.50 and 2.50 alloy rims, 140/70-18 and 110/90-18 Shinko 230 tires, etc... I am going after the best cornering vintage bike I can, but my budget is strained.

What's the expert opinions on the vintage shocks? Aside from "they are cool and vintage?" same price on those, the foxes need new repainted (springs), new seals, new o-rings, and a shaft, and sell for $500-700 rebuilt/restored on ebay, and are very sought after and not very plentiful whatsoever. The Marzocchi's top out at $300 on ebay and are more common. Both are DeCarbon (inventor and name brand) style shocks (oil is separated from the air or nitrogen by a piston or reservoir to cushion the change in volume when the shock shaft travels in and displaces oil) as compared to Emulsion shocks (which let the air and oil mix, foaming up the oil and changing the dampening properties a lot as the oil foams and heats up). Some shocks work like this with a small nitro or air space at the top, but the piggyback allows much greater oil capacity for much better cooling and stabilization of oil temperature for more consistent dampening and no foaming. Nitrogen doesn't change in pressure like air does as it gets hotter/colder, so more gains are to be had there.

 

[Chuck78]

If I can cough up the money, this is what I was originally shooting for:

YSS Z-362 TRL Twin — Gas Shock Absorber
Price: $499.00 per Pair
Available Lengths: 310 mm, 320 mm, 330 mm, 340 mm, 350 mm, 360 mm,370 mm, 380 mm, 395 mm, 420 mm
Type: Self Adjusting Gas Emulsion Shock
Features: Pre-Load Adjustment, Rebound Adjustment 60 Clicks — 36 mm 50 Micron Steel Bore and Radial Sinter Piston — 12 mm Hardened Shaft — Low Friction, Long Life Seal Block — Mounting Rubber and Bushes to suit each Model — Damping and Springrates Model specific — (Included: Ride Height Adjuster (Length Adjuster +10 mm)
Application: RACING ON and OFFROAD — for SOLO, SIDECARS, QUADS, CARS, STREET BIKES

these have a piston to seperate the oil from the gas I have read, basically like a compact version of the external reservoir.


Hagon Type 2810 Adjustable Shock, 28mm sealed damper unit featuring 10 position damping adjustment with automatic compression / rebound balance, 3 position spring pre-load adjustment by enclosed cam. 2 year guarantee.

 

[Kanticoy]

The guy you need to talk to about this is Doug a.k.a. Beatnik on here. He had been inside and out of every one if these shocks and can tell you the benefits and pitfalls of each one. I'd love to hear what he has to say.

 

[Chuck78]

Scratch the Hagon 2810, everyone says go with a custom-tuned-for-you $200 non-adjustable non-rebuildable Hagon, or else drop $500 for the best thing I could ever justify as most of us cannot afford Ohlins!:

Hagon Nitro "The Ultimate Twin Shock"
FEATURES
Stainless Steel Body and Spring
18mm Hard Chrome Piston Rod
Choice of Anodised Colour for Alloy Parts
(Blue, Gold, Black and Silver)
38mm Piston
10 click Adjustable Damping
Fully Adjustable Spring Preload
Hi-Tech Shim Stack System for Improved Damping
Range of Lengths
290, 300, 310, 320, 340, 350, 360, 370mm
Spring Rates 18, 20, 23, 26, 30, 35Kg
Spring: 73mm Outside Diameter
Rebuildable
Adjustment tools supplied

I forgot Dave Quinn (Hagon dealer) told my wife not to buy the 2810's, said I'd be happy enough with the proper valve selection on the nonadjustable classic shock, and to get either that or the more expensive Nitro, a rebuildable top quality nitrogen charged stainless upgraded version of the 2810. "$300 is too much to spend for a non-rebuildable shock when you can get the same performance from a properly selected valving on the $200 nonadjustable classic road shocks."

lhttp://www.hagonshocksusa.com/nitro.htm

So the Fox Shox at $225 (+$180-200 for a shaft and all new seals and eye bearings) or Marzocchi's @ $300 for either are now the "affordable option" as the Hagon Nitro and the YSS Z-362 are $500! But I do get externally adjustable dampening & the exact spring that I need, rather than unknown springs that I may need to swap, as well as valving shim stacks that may need modded to suit my needs and must be torn down to adjust. The Fox shocks look really awesome, and I think I found seal kits for them for $22. I wonder how much a set of springs would cost? My bike is down to 499 lbs w/3+ gallons of gas, and I'm only 165 max with full gear & a few tools. I suspected the fox shocks off of a GS1000 are sprung real stiff for racing applications and a slightly heavier rider, but have since been told that vintage racing shocks are like vintage OEM shocks, still not as stiff as modern offerings - so the rate will likely be right in the ballpark for a sporty street ridden bike. The Fox are re-sellable for sure, so they are tempting me. Marzocchi Strada's seem less sophisticated in the dampening (but probably will function pretty similar) and are much cheaper typically, but less aesthetically pleasing to me. Still are all options however. The OEM 1977 shocks with max preload are too soft & the valving stinks, so I'm sure the rebuilt Fox valved as is will be very nice improvement.

On the YSS Z-362 vs the Hagon Nitro, the 60 clicks of adjustment seems very intimidating compared to 10 clicks on the Hagon... I am visualizing losing track when counting clicks forever...

I read some of RaceTech's suspension bible or whatever it is called to learn a little about the differences. The individual valving on all of the higher end shocks seems all quality but quite varied to my novice knowledge. am I correct in assuming that the 1980's Fox shocks after set up for my likings would dampen just as well as the externally adjustable modern choices (2810&z-362)???

I think for me it's now only between the Fox that need rebuilt and the Hagon Nitro. I am leaning towards getting the Fox for the heck of it if my good buddy would want them on his heavier KZ1000 with the same GS1100E alloy swingarm as I have, as a backup if I got the Nitros & didnt want to mess with spring swaps on the Fox. still on the fence though about theFox, if you all could shed some light on the end results of fox vs modern hagon ride quality.

EDIT - the Hagon Nitro doesn't come in the eye to clevis version, so the Hagon 2810 is the highest up choice in the line for my GS750 or the GS1100E alloy swing arm, both take clevis mounts (fork style) on the bottom. The Nitro and the YSS Z series are still gas emulsion style shocks, and you need to go up to $599/699 in the YSS G-series to get the DeCarbon design with the nitrogen seperated from the oil with a piston. So it seems as if the Fox shox will ultimately be the best dampening, especially considering dampening consistency, that I can afford,

 

[D4N63R]

My opinion based on thinking suspension is pure voodoo and knowing very few people in this world truly understand how it works is this.

A properly setup cheap shock is better then an improperly setup race shock.

you can buy $100 Ebay shocks and have them built for you for lets say an extra $200 and be amazed at their performance. You can buy an $800 shock and then spend $200 having it built for you and be amazed at its performance.

Is this for a race bike? if not then there is no reason to go all out on the suspension, you dont need all the 'clicks' the clicks are for fine tuning only and without seriously working the shock you aren't going to notice the small changes they make without going from full hard to full soft.

I would agree with Dave. No matter what shock you buy to begin with it will need to be built for your weight/bike. You're better off buying a basic shock and having it setup for you then you are buying a really fancy expensive shock and still having to have it setup for you. You have to spend the setup money either way because the clicks dont change the valving or spring rate and those are the two things that really matter.

If you buy a vintage 'race shock' you may be thinking oh great look at the deal i'm getting but the by the time that thing is rebuilt and re valved (assuming all the parts are still available) you end up spending the same money you would have on a new shock.

Long story short. Buy a quality, affordable serviceable shock and have it setup for you. You'll be amazed compared to a stock shock regardless of the name on the case. Dont forget the forks as well!

EDIT: just read your part about the Fox shocks. In my experience I would take a bike a little on the soft side over a bike that is sprung too high, especially if that shock has weak valving. An overly stiff spring with good valving is literally a pain to ride ESPECIALLY on the street. A stiff spring with weak valving is terrifying to ride fast hahaha.

 

[Tim]

FWIW I was planning on picking up a set of the Hagon 2810's for my BMW in the spring, but am interested in what Dave Quinn told you - I'll have to get in contact and see if he can recommend the right non-adjustable set for me. I like them for the money - had a set of basic Hagons on my XS at the start.

Then I was lucky enough to get some RAM suspension out of the UK in the rear, and Race Tech emulators and springs up front, all dialed in by Doug (Beatnik) from DEK Performance.

 

[Chuck78]

FWIW I was planning on picking up a set of the Hagon 2810's for my BMW in the spring, but am interested in what Dave Quinn told you - I'll have to get in contact and see if he can recommend the right non-adjustable set for me. I like them for the money - had a set of basic Hagons on my XS at the start.

Then I was lucky enough to get some RAM suspension out of the UK in the rear, and Race Tech emulators and springs up front, all dialed in by Doug (Beatnik) from DEK Performance.

My wife went to order some 2810's for my birthday last y ear, and Dave told her to either get the cheaper nonadjustable shocks or the Hagon Nitro's. The Nitro's are really really great shocks, and those were going to be my only real choice if buying new shocks. Anything with a nitrogen chamber separated from the oil bath by a diaphragm or piston is going to be much more consistent dampening than an air/oil emulsion type shock. when they are not separated, the oil foams under hard use, and air/oil shocks will be subject to very different dampening characteristics after riding for a short time with lots of bumps, not to mention different air pressures as the air heats up. With separate chambers for the oil and the nitrogen, you have no foaming to mess with the dampening through the valves, and the nitro doesn't expand and contract based on temperature as air does.
I even used the lighter aluminum GS650G fork tube top caps on my bike even though I was not going to pressurize them with any additional air to have to compress, as I thought I could put my ac/refrigeration vacuum pump on the schraeder valves and suck the air out, and then squirt in a little nitrogen and leave it at 0 psi just so that I might see a slight increase in the consistency of the spring rates of my cartridge emulator equipped GS650 forks on my 750.

So for now, and maybe for the life of the bike if I like them well, I have purchased the set of Fox Factory Shox that I was looking at that came off of a neglected 1979 Suzuki GS1000. They need a cleaning and repaint on the springs, polishing on the bodies, a seal kit and new shock eyes and bottom out bumpers, and unfortunately a new shaft on one ( rust pitting), but I will have less in them than a new set of $500 Hagon's, and I believe after adjusting the dampening to my needs, I will be every bit as happy with them as the new Hagon shocks.

I will probably end up repainting the springs all black, as my bike is black and gold, and thought about covering the reservoirs in 2.5" wide black electrical tape just to black them out and not have a scratchable paintjob, while still preserving the (UV faded) red anodizing and original Fox decals, but I may just swap them L-R and R-L to have the less UV-faded side out for display as in this photo.

The springs don't seem too harsh for me, so I think I will be pretty happy with them, but it is too cold and wintry now to take it for a spin, and my bike is still in pieces from the deer collision.

 

[Chuck78]

If anyone knows of a chart with the spring rates of these shocks, the bottom long spring is a progressive (tighter coil spacing at bottom) and have a yellow paint dot, and the top smaller springs have an orange paint dot. I think the manual Fox has for download shows only MX spring versions and their rates. Any other info or opinions on these shocks and the best jet size and spacer stack arrangements for a 500 lb bike and 155lb rider, please chime in!

Also, how many of you would give a big thumbs down to me not repainting the springs in the Fox red and blue scheme? I'll probably go black, but I saw on the Supercharged CB750 Koppa Cafe by Carpy (google search that or youtube), he polished his bodies and chromed the springs, looks sharp, but no Fox decals!!!! My bike is all black, chrome/aluminum, and gold chain and all three brake rotors have gold anodized centers...The new gas tank is black, the green gas tank one got my knee impression pummeled into it when I hit a deer at 57mph in November... Kept the bike upright, but it destroyed my lighting and speedometer, plug and wire, and gas tank... plus stator cover oil leak and bent stator cover bolts! Ouch. I don't think the red and blue would fit in with the cosmetics, but I know they would gain the shox instant recognition when people who knew what they are spotted those colors. I was thinking just black appliance epoxy paint on the springs. The two spring setup with the nylon spacers in between will still give the shocks a more subtle instant recognition in combination with the piggybacks.

I am very happy at the thought of running these shocks, and can't wait til I get new seals and a shaft and get to really road test them!

 

[Chuck78]

I think I am going for a $27/each teflon lined stainless steel eye bearing (heim joint) instead of the rubber eye bushings. Thor Lawson at Evolution Suspension and one other place sell parts for these, and Thor has repro shafts made as well. Fox no longer supports them for ages now. I will have to have the dirt bike version of the shaft shortened up by a machinist to fit the road versions, as Thor is oriented more towards the MX versions, but the rebuild and valving parts are all the same.

 

[xb33bsa]

on mine i am gonna go red and blue ..........
BLACK that shit ain't right
first i gotta get busy and make some new shafts

 

[o1marc]

Powder coat those springs. They'll stay pretty longer that way.I get $20 a pop for doing them.

 

[Chuck78]

Re: Vintage Fox Factory Superbike Shox

Does powder coating affect the spring structurally? I know people that torch car coils to lower them are committing a big sin that softens the spring rate. I wonder how easy it'd be to do with a harbor freight setup or a toaster oven at home? Never looked into it, but how do you apply the "powder" before you bake it?

 

[mydlyfkryzis]

Baking for powder coating does not get anywhere near the temperature and time it takes to soften a spring.

 

[Chuck78]

Re: Vintage Fox Factory Superbike Shox spring rates etc

I checked out the MX manual for the Fox Factory Shox, and here is what I have gotten from it. Installed with the preload in the middle somewhere, my springs measure 6-1/2" (long red progressive spring with yellow paint dot) and 2-3/16" long (short blue spring with orange paint dot).

According to the manual, if it's spring codes are still applicable for the 13.25" long road version of the shock, I probably have the 7-1/2" and 2-3/4" springs that this manual says fit the 13.75" long shocks:

red 7-1/2" spring w/yellow dot
.295" wire diameter
p/n 96-2570
rate - medium-soft
(the other .295" wire w/pink paint dot spring lists 146 lbs/in, so I assume the chart reflects the med-soft as a progressive rate that is softer than that at first and stiffer when the tight spaced coils bottom out)

red 7-1/2" spring w/yellow dot
.306" wire diameter
p/n 96-1515
rate 166 lbs/in

2-3/4" long blue spring w/orange dot:
.263 wire diameter
rate - medium
96-2180

So it seems as if these springs will not be too harsh for me, and I probably lucked out with the spring rates and that the long red is a progressive and not a straight rate. I was going to go with around 110 lbs/in "averaged rate" progressive rear springs in a new shock. Adding the unlisted lbs/in of the short blue spring will decrease the rate, but the tight spaced coils bottoming out will increase the rate a lot upon hard cornering compression. I have no clue how to add the two rates/wire diameters together even using a spring rate calculator, but I think they will be just about right for my weight and lightened bike. Whaddya think? I'm very thankful that the springs are right in the neighborhood of where I wanted, so that I can keep the trademark originals on it!

Now I just have to decide what kind of valving I need after I tear it apart to see how it's set up as-is.

 

[xb33bsa]

thanks for that informative stuff looking ahead for more
there is also some spring rate calculators online to see what you have

 

[Chuck78]

Alrighty, I found my calipers...Here's the detailed info that I need to calculate spring rate:

red 7-1/2" spring w/yellow dot
p/n 96-2570
rate - medium-soft
0.295" wire diameter
2.510" average coil diameter
7-1/2 active coils
(.200, .200, .300" spacing on the tighter spaced progressive coils at bottom - 1.585" total height out of 8.1" total active spring height, .500" space to compress before bottoming and eliminating them from the spring travel)

blue 2-3/4" spring w/orange dot:
rate - medium
p/n 96-2180
0.263 wire diameter
2.500" coil diameter
2 active coils


using the Wallace Racing spring rate calculator, and using a method that "seemed" legit to me using percentages of spring lengths and rate calculations, I come up with this:

red spring 73% of combined spring length:
131 lbs/in initial
178 lbs/in @ 2.22" travel (coil bind on bottom 2 coils)

blue spring 27% of combined spring length:
296 lbs/in

I have arrived at the fact that 2.75" or 27% of the total combined (both stacked) spring is 60% of the stiffness as the other (stiffer) 7.5" or 73%, and that IF the blue coils were the same diameter as the reds then the total spring rate would be 104.5 lbs/in. so 27% of that 104.5 lbs/in is 40% weaker.

If I approach it sort of backwards, 27% of 104lbs/in is 28 and 73% of 104 lbs/in is 76. if we reduce that 28 down to 60% (as calculated in comparing the .263" wire coil vs .295"), we get 16.8 and add it to 76, we get 92.8 lbs/in initial spring rate with both coils together. Is my logic correct??? that would mean that after the two tightest coils are bottomed out @ 2.7" suspension travel, then the rate goes up from 93 lbs/in to 117 lbs/in. After the 3rd lowest coil bottom out @ 3" of suspension travel, then the rate goes up to 131 lbs/in.

So my shock has the following:
93 lbs/in initial spring rate
117 lbs/in after 2.7" suspension travel
131 lbs/in after 3" suspension travel.

My front fork springs are chopped factory springs that are at around 47 lbs/in. a Suzuki guy my size who played around a ton with spring rates and shocks, fork oil, emulator settings, etc., said he ended up running a 43lb/in fork spring and progressive 95/140 shock springs to get the perfect balance. The next size up in rear was too stuff, like 105/150(?). I am at 47lbs/in front and 93/130 rear with this setup, a little softer in the back, but I think this will actually work out pretty darn ideal. Maybe a little extra preload will help arrive at the 131 lbs/in a little faster. Sounds like these springs will be pretty much spot-on for my weight and current fork spring mod! Awesome.

 

[o1marc]

Re: Vintage Fox Factory Superbike Shox

Does powder coating affect the spring structurally? I know people that torch car coils to lower them are committing a big sin that softens the spring rate. I wonder how easy it'd be to do with a harbor freight setup or a toaster oven at home? Never looked into it, but how do you apply the "powder" before you bake it?

Not at all and I will challenge anyone to contradict that and then post the comprehensive test I conducted checking spring rate from every step of the way including chemically stripping them, sand blasting them, curing them in the oven. I got tired of people telling me how they would be ruined from the heat from the oven and more so from blasting them so I borrowed a bunch of springs and an Intercomp spring rater from Bill Elliott and did a full test. All springs were still in the accepted range weight after every process.

Here's a link to the test:http://powder365.com/forum/viewtopic.php?f=3&t=3005&p=37110&hilit=+coil+spring#p37110

 

[Chuck78]

can anyone comment on how the "chrome" powder coating turns out? I am still leaning towards the black epoxy paint, as it is total DIY for me. If I found a good powdercoater nearby I would definitely go that route however. Maybe my bicycle frame builder friend can turn me on to someone.

I am really itching to get this thing going, but it looks like I am going to be doing a solid 2 months of evening/weekend hoise rehab to sell this giant victorian ball and chain house, and probably buy a small 120 yr old fixer upper...

 

[behrboy]

Re: Vintage Fox Factory Superbike Shox

Not at all and I will challenge anyone to contradict that and then post the comprehensive test I conducted checking spring rate from every step of the way including chemically stripping them, sand blasting them, curing them in the oven. I got tired of people telling me how they would be ruined from the heat from the oven and more so from blasting them so I borrowed a bunch of springs and an Intercomp spring rater from Bill Elliott and did a full test. All springs were still in the accepted range weight after every process.

Here's a link to the test:http://powder365.com/forum/viewtopic.php?f=3&t=3005&p=37110&hilit=+coil+spring#p37110

Thanks for that info.

 

[o1marc]

can anyone comment on how the "chrome" powder coating turns out? I am still leaning towards the black epoxy paint, as it is total DIY for me. If I found a good powdercoater nearby I would definitely go that route however. Maybe my bicycle frame builder friend can turn me on to someone.

I am really itching to get this thing going, but it looks like I am going to be doing a solid 2 months of evening/weekend hoise rehab to sell this giant victorian ball and chain house, and probably buy a small 120 yr old fixer upper...

Chrome powder coating doesn't look chrome at all. but more of a shiny silver. I get $20 each to powder coat springs.
Here's a before and after of what I have done with shocks: