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Discussion Starter · #1 ·
My Z1 FR3 had a very harsh top-out - brand new and only used for one full day riding. I followed the various threads on here re checking the oil levels, which I think were a bit low. I topped up the oil, which has helped a bit, but still has a bit of a clunk at the top.

One thing I wanted to check was the point that I should measure the oil level against. Is it against the lowest part of the threads i.e. where the top of the air space will be when the caps are back on?

I couldn't find anything specific on the various threads / links re this.
Thanks guys - the info on here has been really useful.
 

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You measure from the top of the stanchion...

tube to to the durface of the oil. If you look carefully (use a small flashlight) inside the threaded portion you will see a color change, from silver to the same bronze color as your stanchions. That is the point that you meassure from. However, oil height has NOTHING to do with top out. If the fork it rebounding hard enough to create a clunk at the top of the stroke you have a different problem. It's called not enough rebound damping! Since the FR 3 does not have adjustable damping there are only two ways you can cure this. The first is to go to a heavier weight oil, say a 10 or 15w fork oil. Or you can use lighter springs in the fork or less preload. If you are already using minimum preload then a lighter spring may be in order for your weight.

I would try the heavier oil first as this will slow down your rebound a bit and should take care of the harsh top out.

Good Dirt
 

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Discussion Starter · #3 ·
Squash said:
However, oil height has NOTHING to do with top out. If the fork it rebounding hard enough to create a clunk at the top of the stroke you have a different problem.
The reply I got from Marz doesn't sound consisteny with this - their response was:
You might need to check your oil level to make sure it is not low. the oil height should be set at 50mm with everything compressed.
THinking about it, as the oil provides the damping, wouldn't oil level have some impact on rebound? Even if it's not the main factor, it would surely have some relation to it?

I think I'll ride it a little longer before moving to a different oil - it's only had a day at Diablo so far, so I haven't really had a chance to try it on regular trails.

Re the springs, I'm around 155lbs without gear - I'm assuming that the normal springs should be about right?
 

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carpe mañana
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Oil level has a lot to do with rebound. If the oil is low then as the fork approaches full extension, the damper eventually goes though all available oil and all there is is air, so it speeds up with the noticable topout.

You measure the oil level from the top of the crown threads, pretty much from the top of the crown. The easiest way I found is to mark the spoke 50mm or whatever distance you're shooting from, from the end and insert it until that mark matches up with the top of the threads. If it comes up dry, add more oil, if it comes up moist at the tip, you're done, if you have oil on a couple of threads, then you put a tad too much in there.

Most every time I had issues with topout it was due to low oil.

_MK
 

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Sorry, my bad, I should learn not to....

reply to posts before I've had my first cup of coffee:blush: ! You certainly will have top out troubles if you don't have enough oil in your fork. What I meant to say is that oil LEVEL may not be relavent to your fork. Many Marzocchi forks now use oil volume in CCs NOT oil level to determine the correct amount of oil for the fork. You need to check the Zocch website before trying to set your oil levels using the measurement method. Many of the forks with ECC and ETA cartidges require more accurate volumes to function properly than the old oil level method provided. If I remember correctly the FR 3 does have an ETA cartridge and one side does contain an adjustable damper (unless you have an OEM model that for some reason is not the same). You can still visually check to ensure that your dampers are completely submerged in oil through the full stroke of the fork. As stated, remove the caps and springs, compress the fork, shine a light and look. Anyway the point is, check the website and see whether they list an oil volume in CCs or an oil level in MM for your fork. Use the method that is designated for your fork.

And by the way, the proper method for oil level mesurement is still from the top of the stanchion, not from the top of the crown. It even still states this on the website under oil levels. The stanchion tubes do not go to the top of the crown. The difference in using the top of the crown is only about + 2 or 3mm but it can make a difference. However the main thing is to measure consistantly from the same spot. It only becomes critical if you are trying to run the absolute minimum oil level. But as I said, it may or may not be relavent to his fork.

Good Dirt
 

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that's wierd that your having topout probs...i got the same fork earlier this year and have no trouble with it...if you bought it new, they should be doing the work on it...but it will take a while though...mine is the 130 variety...your is 150 mm? could a bit of air preload help to solve the problem?
 

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Discussion Starter · #7 ·
Re air preload, I'm getting the approx the right amount of sag with no air preload - not sure how adding more would impact the rebound? It is the 150mm version.

Anyway the point is, check the website and see whether they list an oil volume in CCs or an oil level in MM for your fork. Use the method that is designated for your fork.
On the oil level - all I have to go on is the reply I got from Marz tech support who advised to go for 50mm as per my previous post. I couldn't see anything on their website or the manual re oil levels - that option on the website didn't seem to work.

The FR3 doesn't have any external adjustments, so oil level / viscosity are the only things that can be adjusted.
 
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