[a11y]

Hi folks

I'm hoping for some advice here. I've just completed an oil change on my 2006 66SLs - found it very easy - but something's not right now. I can only get a maximum of 125mm of travel from the forks, even after blowing the air out of all the chambers (2 x positive, negative, PAR) and compressing them unweighted. The fork just physically can't be compressed beyond 125mm of travel, so I'm missing a good 45mm of travel...

Does that sound like the oil level could be at fault? i.e. too much oil? I'm a bit of a beginner when it comes to fork servicing and technical knowledge of how they work, but I suspect the oil level is incorrect and excess oil is stopping the fork compressing - does that sound feasible? If it is too much oil, which leg is it likely to be: right (non-disc) or left (disc), or both?

I used 7.5wt oil and followed the guidelines in the Marzocchi service manual of 50ml in right leg (non-disc), and 200ml in the left leg (disc side). However, I've searched on mtb.com and found mentions of 40ml in the LEFT and 200ml in the RIGHT (http://forums.mtbr.com/showthread.php?t=160024). Is the Marzocchi service guide wrong, has the person on mtbr got it wrong, or does it sound like I've messed up? Either way, something ain't right!

Hoping someone can shed some light on this. Thanks, a11y.

 

[tacubaya]

10ml in the Doppio side won't reduce the travel (oil in Doppio side is just there for lubrication), it is very likely that you did not cycle the RC2 cartridge enough times to remove oil that was inside it, so when you added the new oil you overfilled it.

Remove 20ml from the RC2 side and see how much travel you get. If you don't get enough travel then remove 10ml again and continue until you get almost full travel.

Tip for next time:
You should remove the oil that is outside the cartridge and then turn the fork upside down and cycle the cartridge rods to remove excess oil. Then add 190ml to the RC2 side and 50 ml to the Doppio side.

Cheers

 

[a11y]

Thanks tacubaya :thumbsup:

I didn't realise the oil in the doppio side was just for lubrication: 50ml sounds like a lot of oil just for that purpose, I'm used to working on Rock Shox and just using 15-20ml in each leg for lubrication purposes. That's good to know.

I'd spoken to a riding buddy last night after posting my Q here and he's said exactly the same - that I didn't take enough time/care draining the old oil from the RC2 cartridge, meaning I've now got too much oil in that side. I'll try your advice later this morning once the coffee's kicked in, not as if I can go riding as there's waaaay too much snow here

 

[lostboyz]

I am doing the same with my fork. I belive the service manual is wrong and that the oil level should be 50ml(PAR Side)on the left and 200ml on the right. I am going to try 10wt on the RC2. I run 10wt on compression and 7.5wt on rebound on my 888 and have had good results with that. Please respond with your results. Thanks!!

 

[tacubaya]

How do you guys cope with the stiction on the Doppio cartridge after some of the oil has come out of the negative valve? Do you guys send it to Marzocchi or you guys open it up and lubricate the PAR piston?

 

[lostboyz]

I will open mine but the question is...how much oil will go inside? I wont open it until I know how much to put in. The 50ml that goes in that leg should lubricate the cart well enough....im guessing.

 

[tacubaya]

Doppio cartridge is sealed and has its own internal lubrication.

 

[lostboyz]

How much oil goes in the doppio? 50ml?

 

[tacubaya]

IN the doppio cartridge? Nothing.

In the doppio side of the fork? 50 ml.

 

[lostboyz]

Ah, gotcha....Im just curious as to how the doppio is lubricated internally if there is no oil inside of it. So, 50ml in the doppio side and as long as the doppio holds air all is good. Stiction is why most dont prefer air forks...I have excepted that.

 

[tacubaya]

It is lubricated internally by light grease. I just called Marzocchi to confirm.

 

[a11y]

Finally...

Well, I'd just been an idiot during my first attempt and had got the legs mixed up: I'd put 200ml into the doppio side and only 50ml into the RC2 side, instead of the other (correct) way round - doh :blush:. I drained the oil out into seperate containers, then reinserted the correct amount of oil into each leg, but because of residual oil within the RC2 cartridge I had to play around with the amount in that leg until I got full travel unweighted. It was quite easy to judge if too much was in there by compressing the upper legs into the lowers: the oil level becomes visible inside the lowers, so it's easy to tell if you're going to have too much.

I haven't yet been able to test-ride them to achieve the full travel while riding (haven't got any surface free of ice/snow) but could get 130mm+ just bouncing around inside the garage.

 

[MK_]

IN the doppio cartridge? Nothing.

Nothing? You surely want a cc or two in there to keep the seals lubricated. 2.5wt or 5wt oil, no?

_MK

 

[tacubaya]

Marzocchi tech said just to lube the PAR piston but yeah, some float fluid or a bit of oil should be a good idea.