Now I've done it . . .

[dlaing]

For a greater understanding of fork fluids and oils.

http://www.peterverdonedesigns.com/lowspeed.htm

important as it shows that the weights don't match the viscosities across brands.

The "Cartridge Fork Fluids" tend to have wider temperature ranges, but many "fork oils" also have wide temperature ranges.

I would look for something with a wide temperature range rather than the marketing term "Cartridge Fork Fluid". Maybe there is more to it than that, but until proven otherwise, I'll go with the information in those charts and simply look for a wide temperature range, in my desired viscosity.

[docc]

Based on Verdone's work using cSt@40C it looks like most of the 'light' fork oil is still too heavy. I didn't like the Maxima oil I ended up with, but it looks to have about the right 'target' value of 16.00 cSt@40C ( actually 15.90).

 

The Silkolene 5wt is rated 22.30. I have ended up with the 'heavier' Silkolene 5 wt in the rebound fork and the 'lighter' Maxima 5 wt on the compression side. Backwards by default?

 

His chart on conventional slow speed damping adjusters is revealing. He shows that the adjustments are more sensitive in the first part of the range while making less and less difference toward the end.

 

My estimation from the chart is that 10% of the 'clicks' is 25% of the damping; 40% of the clicks is 65% of the damping.

 

I'll have to look, but I think I have the rebound adjuster on the fork turned in 75%. Based on Verdone's chart that is 95% of the damping. If I want 75% damping I should only turn in half the available clicks.

 

 

 

+ =

[Guest ratchethack]

+ =

I like it, Docc. IMHO it's both profound and accurate.

[docc]

I tried for the 15 minute fork spring change.

 

Add two three minute sessions of drumming on the practice pad to Pink Floyd and The Police.

 

Add 20 minutes for setting one spacer on top of the spring and dropping the other spacer into the depths of Hell without thinking to put the spring in first.

 

Add 20 minutes to release, and reset the rebound spring for the squeeking-scraping sound when jouncing the forks.

 

Add 20 minutes to discuss the awful sound with TD.

 

Add a 45 minute ride to see if the spring will 'center up.'

 

Add an hour to make PVC spacers only to find the same scraping-squeeking upon reassembly.

 

Another 30 minutes to pour and drain single malt and lament the fate of the mechanically engaged.

 

Should the springs make noise like this? The sag looks good, I think, at 21mm static and 35 mm laden. It rides nice and I can't hear the noise while in motion.

 

But, I am afraid of having bad dreams about stiction and wear and particulates in my fork oil.

[Guest ratchethack]

...the squeeking-scraping sound when jouncing the forks...

 

Should the springs make noise like this? The sag looks good, I think, at 21mm static and 35 mm laden. It rides nice and I can't hear the noise while in motion.

 

But, I am afraid of having bad dreams about stiction and wear and particulates in my fork oil.

Hmmmmmmmm.

 

This is a bit of a puzzler, Docc.

 

FWIW, your sags look very good IMHO, and you've gotta be pleased with this!

 

I'd start by measuring the stiction, per previous discussion if you recall. This will either put your mind at ease or indicate a real problem. If you're getting much beyond 2 mm stiction unladen, I'd say there's definitely something amiss.

 

If beyond 2 mm stiction, ck the following:

 

Have you aligned and assembled the fork in the correct order to prevent setting up internal stresses and binding?

 

Any chance of a kink or other damage to a fork tube?

 

Can you feel anything binding by extending and compressing the fork through its full stroke with springs out?

 

Don't recall if you'd completely dismantled the forks. If so, did you inspect the bushings? Roll the tubes to ck for true?

[docc]

Y'know, everything seemed pretty good before installing the new springs. My old sag numbers were sorted, but required too much preload to achieve. Topping out was too easy.

 

The new springs really don't feel much stiffer, but do require less preload for the optimal sag. They are an inch shorter than the originals and measure 1.35" OD ( original Marzocchi 1.37").

 

I guess I'm lost on the stiction discussion and how to measure it.

 

Yet, going from the familiar "squeesh-squeesh" before to "scrape-squeel" doesn't sit well with me.

 

I just dropped the springs in and put the spacers on top. Am I missing something???

[Tom M]

I just dropped the springs in and put the spacers on top. Am I missing something???

 

That's pretty much what I did and I don't have any scraping noises at all. Is the noise in both legs or just one?

[docc]

It's in both legs. It sounds like a swing set more than a hydraulic component. If my lawn mower made this noise I'd take it apart.

[dlaing]

What did you do with the blue nuts?

Are they at the same adjustment point as before?

Not sure why that would create a noise, but it might?????

More likely, the new springs are the wrong size.

You might take the springs out and measure against the OEM.

I am sure you were dreading that, but with practice, you can get it down to 15minutes.

[docc]

The trick with the blue nuts ( sounds like it would hurt ), aside from being sure they are right side up, is to make certain they screw on far enough that the caps bottom ( or 'shoulder') completely before using them to lock the caps.

 

I also learned from the Traxxion Dynamics excellent instruction package to preseat the rebound adjuster.

 

The handling just keeps getting better. Tonight I did about 10 miles of high speed ( 85-95 mph) cruising past interstate trucks and such. I thought I had the weave sorted well before, but the high speed stability is remarkable with the new shock and springs.

 

Four of my experienced and trusted companions listened to the noise this evening and shrugged saying, "Yeah, sometimes they do that." Sort of the same thing Traxxion said.