About fork oil....

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anteva2

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I have a question ... I recently changed the springs on my 2002 Max for progressive Hyperpro. The question is that the manufacturer adds a 1 liter bottle of fluid and according to the service manual the quantity for the forks (the last widest) is 619 Cm3 per fork. According to the mechanic it is not a problem in its performance and he has distributed the fluid between the two (500 cm per fork).
I also read according to the manufacturer, that once these progressive springs are installed, it is not necessary to add pressure to the fork ... Is this true?
I have no idea if my mechanic is right or if I should add the missing fluid to each fork.
Thank you guys so much.
 

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Hyperpro state in their fitting instructions
"Fully compress the fork and fill it with HYPERPRO fork oil of the right viscosity (see label: HYPERPROOIL), just below the required level (see label: OIL LEVEL). Pump all the air out of the fork by compressing and decompressing the fork (± 10 to 20 times)7To measure the oil level (air chamber): fully compress the fork and do not fit the spring, spacer and other loose parts.Make sure the fork is compressed in the hydraulic lock; when compressing becomes heavier, push further until steel to steel contact is felt. The oil level is the distance between the top of the tube and the oil inside. Hold the fork straight up. Use a tape measure; slide it in until it just lightly touches the oil in the fork, hold it against the upper edge of the tube and read.Add or remove oil until the required level is reached (see label: OIL LEVEL). Make sure there is no air in the fork "

What I haven't been able to locate is the label they refer to.

IMO to get the best from the springs you will need to have the correct amount of oil in the forks:
a) too little and there is the potential for the oil to become aerated which will negatively affect the damping.
b) Too much and there is the potential for hydraulic lock.
c) The air above the oil acts as a spring and this will (should) have been taken into consideration when calculating the spring rate. Too much or too little will affect how the springs perform.

As they make reference to the oil level then that suggests that they consider it relevant and I would instruct the 'mechanic' to do the job properly.

I haven't seen any reference to adding air into the forks so on that basis I wouldn't.

And to continue preaching one of my mantra's, page 25 gives instructions on setting the static sag. I assume your 'mechanic' has done this?
 
Since you're expressing volumes and measurements in metric nomenclature, I suspect you are in Europe? Please consider adding your location below your screen name/avatar, also your bike info where you can add a signature. These things alert us to your location so perhaps someone close-to you may volunteer for assistance, or know of a reputable shop to whom they may refer you. It also helps us to know for what market your bike was designed, i.e., a full-power USA version, or a Japanese no VBoost model.

If you look at the VMax website, you will see there is a heading for directions from manufacturers. Please take the time to scan your instruction sheet and to upload it to there. Another time and labor-saving way to show interested parties exactly what that parts manufacturer is telling you to-do.

Forget that last paragraph, I uploaded a lot of their info into a thread under the heading Factory Instructions and entitled, Hyperpro Suspension

I see here is their USA distributor info:

EPM Performance Import

77 Pension Rd
Manalapan, NJ 07726 USA

Email
732-7869777
732-7869777 (Fax)

Website
HYPERPRO CATALOGUE - SPRINGS MANUFACTURER/MODEL YEAR REMARKS
FORK-KIT
SHOCK-KIT PURPLE Black version add: COMBI-KIT PURPLE Black version add:


V-MAX/ VMX 1200 88-92 FORK D=40 MM SP-YA12-SSA004 SP-YA12-SSD004 B SP-YA12-SSE004 B
V-MAX/ VMX 1200 88-92 FORK D=40 MM CHROME REAR SP-YA12-SSA004 SP-YA12-SSH004 SP-YA12-SSI004

* SPRINGS ARE ALSO AVAILABLE IN BLACK * SPRINGS ARE ALSO AVAILABLE AS LINEAR
V-MAX/ VMX 1200 88-92 FORK D=40 MM OHLINS TWIN SHOCK SP-YA12-SSA004 SP-YA12-SOD004 B SP-YA12-SOE004 B
V-MAX/ VMX 1200 93-07 FORK D=43MM SP-YA12-SSA005 SP-YA12-SSD005 B SP-YA12-SSE005 B
V-MAX/ VMX 1200 93-07 FORK D=43MM CHROME REAR SP-YA12-SSA005 SP-YA12-SSH005 SP-YA12-SSH005
V-MAX/ VMX 1200 93-07 FORK D=43MM OHLINS SP-YA12-SSA005 SP-YA12-SOD005 B SP-YA12-SOE005 B

[end]​
OK, I found this: Hyperpro-Spring-manual-v3.3_EN.pdf
 
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Fire Medic...."Touché"

Although I think you already know, from other conversations, that my model is the Euro 2002 version to which a Vboot kit has recently been installed, trimmed diaphragm springs have been added and the stock exhausts have also been removed. 25mm by 35mm stock exhausts.

Still, I'm waiting to install some new steering bearings, although the wobble before the progressive springs was coming in around 110 mph. now appears at 125 mph. Still I know I can still squeeze in some mph. more, but that if, safely.

Thanks for your comment.

And yes ... my English is awful
 
Thanks for the additional info, I see so-many bikes on-here, I forget particulars on someone's bike unless it's written in-front of me when I open a thread, in the signature. That helps me to know what info is relevant.

If you don't yet have radials, consider getting a safe wheel for the rear, to allow you to run 17" or 18" dia tires in radial configuration, and if you decide to use the 18" OEM front rim, don't go any wider of a tire on the OEM rim, like to a 120, or larger, as the OEM front rim is really too-narrow for what is recommended for a front radial tire in its optimal size. Running properly-sized radial tires/wheels, rated for the speeds you are going, is what I consider the best handling enhancement you can do to a Gen. 1.
 
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