Andreani upgrades for V11 OEM Marzocchi forks

[Gmc28]

Updates @Meinolf?

[ChrisPDX]

Hi Friends.  

I have a 2001 "Greenie" that I've recently rescued and put back on the road.  It has the early silver 40mm forks, and I went down several of the roads described in this Technical Topic before finding success.  Sharing here in hopes it helps.

Short summary:  The early 40mm silver forks do not accept modern replacement cartridges from any source I could find.  I ended up sending the forks to Traxxion Dynamics in the USA and for a quite reasonable fee (about $600 in 2024 $$, less than 1/2 the cost of new cartridges) they changed the springs for my weight, new seals, and re-valved the stock cartridges so the rebound cartridge now serves both purposes, with rebound being adjustable and compression being fixed-but-functional. The stock compression side acts as delivered from the factory, which is basically only in the last 1" of travel - think of it as bottom out control.  Turnaround was 2 weeks plus shipping time.  They were very responsive via email, and super knowledgable/helpful and willing to work on oddball projects like this one.  I'm not representing myself as a true suspension expert, but did 20 years as a club racer so over the years have been on some fancy Ohlins stuff as well as my share of Vintage Wobblers :). The end result on the V11 is VERY nice. I have no relationship with Traxxion other than as a satisfied customer who paid their full asking price.

Longer story:  My 2001 has 15K miles on it and almost certainly contained the original fork oil and seals.  I decided to replace oil and seals myself, and to evaluate other upgrades later after riding the bike awhile.  So begins many of my mechanical "journeys".  :).  Upon disassembly I thought, "Well...while I'm here...I REALLY ought to get springs for my weight."  So, I called RaceTech, discussed with their vintage technician, and ended up with a set of .90 springs to better support my 170lbs/77kg.  I cut preload spacers (210mm) to achieve 15mm preload, and worked out the 10wt oil amount to achieve 120mm air gap.  BUT, when I assembled the forks I pushed them through the full stroke and had a "....whuuuut?" experience, because the compression resistance without the spring in place felt like - nothing...nothing...everything.  This is as-described by another forum member, but I didn't get it until I actually felt it.  That feeling caused me to stop.  Honestly, I walked away from the project for a week, to ponder.  It had felt so wrong, but I'm familiar with the cost of new cartridges :).

In the end I reached out to a couple local race sources.  They typically do Ohlins, GP, and Ktech cartridges for R6s and the like, and were polite but reluctant.  I then reached out to Maxton, but they responded they no longer do work on bikes for the USA due to insurance restrictions.  Then I reached out to Traxxion Dynamics in the USA.  They were willing to look at the forks, asked for photos, and recalled they'd previously installed custom cartridges in 43mm Marzocchi's for a V11.  My photos of how the top of the 40mm forks assembled caused them to say, "Looks similar, and we've figured out many applications, we're willing to try."  

When the forks arrived at their facility they disassembled and were surprised.  They said, "...these fork tubes and axle clamps are not threaded as usual.  The cartridge is what's holding the fork tubes and axle clamps together.  They have a massive steel cartridge body, and our cartridge is too small diameter to accomplish the same task."  I believe this would be the same answer from any/all modern cartridge suppliers.  The 40mm Marzocchi solution is unique, and is no longer (was never) the industry standard.  

But, Traxxion did say they could re-valve and re-spring the stock cartridges to improve what I'd sent them.  

I agreed to that, and upon further disassembly and consideration they sent additional evaluation including - a. the compression cartridge really doesn't do anything until the bottom of the stroke, b. compression and bleed needles were both missing springs which meant "clicker" adjustment did nothing, c. those needles don't have taper...the list went on.  All of which got fixed with replacement parts from the Traxxion tool box.  

In the end I ended up with forks where the rebound side does all the damping work in both directions.  Springs are 1.0, which are what Traxxion recommended for a 170LB rider on a 550LB bike with 25 degrees of rake.  I can share, after riding it, that the front end is what I'd describe as plush-but-supported, and around town my fork zip tie shows I'm using about 225mm of travel.  It's, frankly, great (kudos deserved, in part, to the Penske shock I put on back, which I'll detail in another post in the Technical section on that subject).  The solution feels fully complete, not 1/2 way or some version of tolerable but better.  It's good.  And not wildly expensive.  I'd highly recommend this approach, even on the 43mm forks where more alternatives exist.  

Thanks for listening.  Hope this saves someone some time, $$, and results in more bikes that handle in a confidence inspiring, safer, more comfortable, and truly enjoyable manner.  

 

[guzzler]

Thanks for sharing this mate!

It's what it's all about eh,sharing what we've done and the results in the hope it helps others!

The standard non- existent comp damping then everything in the last 25mm was downright scary in certain bumpy corners, jeez it used to deflect and bounce hitting them in a straight line! Fixing this is the BEST thing you can do to the bike.

Cheers  

[GuzziMoto]

The lack of compression dampening in the first gen forks is fairly well known, but I can see how someone new would not have known. We probably haven't discussed that in a while. The easy button fix for that is to blank off / cover up one of the two bleed holes that allow the fork oil to get out of the way of the piston without having to go through the valving in the piston. I would not cover / block off up both bleed holes (as I recall there are two of them) as leaving one open seems to work best with the stock valving in the piston. But it may be that with different valving in the piston that can flow more oil you might get good results by blocking off both holes and forcing all the oil through the piston. I am not sure about the adjustments not working, but for sure if you block off one of the two holes and force more oil through the piston valving the adjuster becomes relevant and adjustments to it make a difference. But with the stock bleed holes the compression adjuster for sure only affects the last inch or so of travel (the part of travel after the piston has gone by the bleed holes in the cartridge).

Also, having compression dampening ion one leg and rebound dampening in the other leg is not how all forks do it but a number of forks do it that way and there are even advantages for doing it that way. It can work fine that way. There are design issues with the first gen forks, like the compression dampening not mattering until the piston is past the bleed holes, but the separation of compression and rebound dampening to their respective legs is not one of them.