50mm Marzocchi preload. Recommended setting please?

[BillO]

The pre-load is how you adjust the sag... more pre-load = less sag.

Because rider weight affects the spring rate you use.

If you have the correct springs for your weight according to LTR 5-7mm of pre-load should get you the correct sag.

Later,

Sorry for reviving and old thread.

I agree with Jake on this. For off-road, use the minimum amount of pre-load you can get away with and still keep the spring from being lose. You adjust rider/static sag with spring rate. If you have too much sag use a stiffer spring - too little sag use a softer spring.

 

[ray_ray]

yep .... I like these forks very much as they at least give you an option for changing \ fine tuning your sag to some degree without being forced to reach for your wallet as the ~only option for setting UR forks (sag) up to fit you and your riding ...

Reviving an old thread? ...This is the power of computers \ ~email ...

 

[moto66]

I got the bike all buttoned back up. My measurement came out to 41.6mm. Judging from your number of 35mm +/- 10mm, I should be good to go!

Thanks!
Andy

Hi Andyman, just in the process of getting my 09 SMR back together and have always found the front dives a bit, despite adding compression. I'm slightly lighter than you, prob by 10lbs with gear, what did you settle with for preload on the ring adjusters and how have you found it? Also - as not got forks apart - just remove fork from clamps, undscrew top, slide down leg outer and move ring up/down - I'm assuming? Thanks

 

[andyman]

Well, at the time, I thought it was better, but I've recently gone back to the stock setting.

Your assertion is correct about how to get to the ring adjusters. It's pretty simple.

 

[moto66]

Did you move the clip much?? I think just firming up slightly and backing off the compression, which is currently compensating for a lack of preload. I'm no track racer but likewise hate a poor set up. Was also thinking swapping out the OE oil now they've bedded in somewhat. Was yours grungy or like new?

 

[andyman]

Oh mine was definitely grungy. I have right at 30 hours, and have replaced the fluid twice. Grungy both times.

What I did with the pre-load was find where the spring was not pre-loaded, then moved the clip one notch down... which I think ended up being the stock setting.

 

[ray_ray]

The oil in my forks is always grungy looking... Not sure why as I have cleaned it well before replacing it and in the outer chamber, what is really going on in there? Not much that I can see , just lubing the tubes and how hard can that be? ... I'm just straining it now before replacing it ...

That pre-load clip is great ... but if you get to adding more and more load, it will finally get to where to have to remove the inner chamber and drain the oil from the outer chamber to move the clip OR find a clever way of pulling the spring upper stopper piece up by grasping it at the top only ... I tend to like my forks starting up high in the stroke on the trails ..

The fluid volume makes a big different in the feel of the bike also ...

 

[moto66]

Interesting the oil comes out grungy, perhaps it due to the alloys in the forks? I just thought same as the motor, it'd be a good idea to do now the bike has done it's run in. Re the preload, I'm running only road and prefer a firmer set up so I'll go with a one notch down from what it is now and see how that feels. Put in some fresh oil too. Thanks for the advice

 

[Degg]

The oil in my forks is always grungy looking... Not sure why as I have cleaned it well before replacing it and in the outer chamber, what is really going on in there? Not much that I can see , just lubing the tubes and how hard can that be? ... I'm just straining it now before replacing it ...

That pre-load clip is great ... but if you get to adding more and more load, it will finally get to where to have to remove the inner chamber and drain the oil from the outer chamber to move the clip OR find a clever way of pulling the spring upper stopper piece up by grasping it at the top only ... I tend to like my forks starting up high in the stroke on the trails ..

The fluid volume makes a big different in the feel of the bike also ...

DO YOU KNOW WHAT THE STANDARD FLUID VOLUME/HEIGHT IS FOR A 09 WR300? I MEASURED 130MM AND THE RIDER WAS COMPLAINING ABOUT BOTTOMING.

 

[Vinduro]

LT-racing recommends 5-7mm of pre-load.

Mine is a 250 with different springs but I ended up with the clip on the 9th groove down from the top. Stock it was on the 8th. The springs had settled when they were new and there was no preload so I was getting some clicking when coming down from full extension. Going to 5-7mm of preload fixed the problem.

Later,

 

[Vinduro]

Why is the static sag used here? Why is the rider not on the bike when setting the front end sag?

You need to use static and rider sag to make sure you have the correct spring for the bike and rider.
You want approximately 14% of available travel in static sag. You want 25% in rider sag. On the Marzocchi that means about 40-45mm in static sag and 75mm in rider sag.

 

[Vinduro]

I got the bike all buttoned back up. My measurement came out to 41.6mm. Judging from your number of 35mm +/- 10mm, I should be good to go!

Thanks!
Andy

10mm + / - too much variance. You need closer to 2-3mm variance. BUT, Your 41.6mm static sag is about perfect. Now see if you have 75mm rider sag. If so then you are good to go. IF not, you need to get as spring you can. Vary your preload to get the correct static sag.