Xeron

Ok, I’m really confused right now about shock oil. Over here in the UK we seem to generally measure the weight of our oil like 10, 15, 20, 25, 30, 35, 40 and up but not really much higher than 100. I’ve noticed other people referring to thousands, 2000, 3000, etc.

Now, A while back a few people came to the conclusion 2000 = 200 in our terms. As the FG MT has 2000 in and we all thought it was to hard and we were putting 50 in, which would be 500.

Ok, so how am I confused? Well… I noticed some conversation saying they run 3000 in their FG Marder.. I thought what? That’s hard! I went looking at shock oils, I noticed it seems to go up in steps of 500… 2000, 2500, 3000, 3500… oh? Interesting… This then made me think well surely it works like this:

1000 = 10
1500 = 15
2000 = 20
2500 = 25

Where as before I was under the impression it worked like this:

1000 = 100
1500 = 150
2000 = 200

This seemed odd because they are such thick oils… in UK terms (100 – 200) So I then said was this guy running 300 or 30 then… I run 45 in mine… so surely hes running 30, no way can it be 300, can it?

So, if the conversion does work like I now think (1000 = 10) why do people say that the MT comes with 2000 (20 :S?) when its so thick! It looks more like 200, its like hypoid oil! Where as 20 would be very watery… but wait, if it is in fact 20… then why are we putting 50 in? even thicker. Well I know my bottle of 50 is a lot thinner than what came out originally. Have a confused you yet? Because I’m lost! I know that I put 45 in my Marder… is that going to be 450 or 4500. big difference. In marder terms it makes sense if this guy is putting 3000 in and I’m putting 4500 in… but in MT terms… why take out 2000 and then put 5000 in. eeeek.

Someone? Can you clear this up?

fire01

Could it be diff oil....or i m missing something also

rubaga

No its not diff oil. Its just the way FG measures its oil for shocks. Goes from 100 to 10000. However, I have seen 50 also in the local shop and used it for the winter. Winter here is quite cold. Basically bigger the number thicker the oil.

BILKO1

Its very confusing my lhs sells protech oils he's go all the oils that protech make i.e. http://www.protech.be/BrowseProducts...GroepID=300001 all i know is the 100000 is for diffs

rubaga

I agree that it is rather confusing that each brand has its own numbering. However, in this forum most people use FG system of numbering. For your reference I attach a copy of page 142 from FG catalogue listing FG shock oils with viscosity numbers.

Regards
Ruben

MichyMuck

Also try this link for reference if you are in the US and Canada.

[link]http://www.twf8.ws/new/tech/tip/shock.html[/link]

I'm going to try 80WT Associated in my MT and see if it makes any difference from stock. If what the data says is correct it should be noticable.

If anyone else has clearer information please post!

Automan

I have just ordered Redline 2bottle of extra light, and 2of light weight, i didn't really know what to get for my Fg MT. Do you guys think I'm way of if i use these ? and witch would you recommend ?

For info: www.redlineoil.com/pdf/10.pdf

Thankful for any help on this, looking around the forum and google just makes me more [sm=confused.gif]

daytona7

MichyMuck,
You have a better link to this site? Unable to access/not found.

Automan

For those of you just entering 1:8 scale racing. Just a little story about shock-fluids.

In the beginning of the 80's cars were equipped with small shock absorbers. The shock fluid used was normally a kind of transmission oil. These oils always changed in viscosity (thickness) during use and temperature. Therefore all kinds of products were tried. Even STP oil was used, you then had to warm up your shocks before racing with a hair dryer before you could use them. Fortunenatly silicone oil was introduced in the mid 80's. This type of oil has an better constant viscosity over a wider temperature range then other fluids but still is not stable. The thickness of the oil is officially rated in Centi Poise "Cps". An other known American rating is WEIGHT "WT". The thinner the oil (fluid) the lower the number, the ticker the oil the higher the number. For normal shock absorber use, this rate may vary between 100 Cs until 500 Cs. Nowadays we use O-ring sealed diffs, so we can use silicone oil in the diffs instead of thick grease. For diffs the rate may vary between 1.000 Cs (loose) up to even 500.000 Cs (very, very, stiff).

Some USA based companies are still using the "WT" weight rating, where Japanese and European companies use the better linear industry standard Centi Poise rating. A lot off people think that the ratings between the "WT" and "Cps" ratings are linear but this isn't the case. For shock absorber use, this is the comparison table when using LOSI, ASSOCIATED and SERPENT some others silicone oil rated in "WT" "W" or are not labeled with a rating but just a number like 30/300


un official conversion values provided by Gene Hickerson USA
Cps Associated WT Losi WT
100 10 7.5
150 15 12.5
200 20 17.5
250 25 22.5
300 27.5 25
350 30 27.5
400 32.5 30
425 35 32.5
450 37.5 35
500 40 37.5

The 50 Cps steps between "Cps" rating are linear, where the 5 WT steps used in the "WT" rating are progressive compared to the real thickness of the oil.
No one can tell TEAM TWF8 how WT rating is measured!!!!! If you know it let us know! [email protected]



Serpent oil (04-01-2005)

W Cps

20 107
25 207
30 370
35 626
40 1070
45 1449
50 2250


How does the measurement works?

A vacuum sucks the oil that is in the bottom of the tube up into the front tube. As soon as the top fluid level of the fluid has passed the top (HIGH) sensor the vacuum drops automatically and the oil starts to flow back. A timer is started automatically. As soon as the the fluid level passes the other sensor (LOW) the time counting is stopped! The time it takes for the level to go from the high to the low sensor is the time we need to calculate the viscosity of the fluid.
As we know the amount of oil, the time it takes and the diameter of the calibrated hole we can calculate the viscosity in mm²/s. Then we have the viscosity in Centistokes value.
Centi Poise (nowadays called Pascal per second) is the result of the Centistokes value magnified with the density of the oil.
Normally for silicone oil this value is 0.9875 = almost 1.0

To perform the whole measurement accurate and constant we have to calibrate the whole system first. Normally this is done when the tube is placed in a water bath that is keeping the whole measurement set up on same temperature @ 22 degrees Celsius for the whole measurement. A calibration fluid is used to check if the reading is correct or need to be adjusted before the real measurement takes place.
Then the tested oil is placed into the tube and the test is performed. As not all oils are the same in viscosity, there are different tubes with a calibrated hole to get the appropriate and corresponding readings.

Although everybody thinks silicone oil is not affected by temperature, we can wake you up out of that dream. When the same test is done @ 12 or @ 32 degrees Celsius we get other values.
Test result from the Akzo Nobel laboratories provided us with the following fist rule:

When temperature is 10 degrees Celsius lower or higher the viscosity decreases or increases by 5%. Example:

200Cps @ 12 degrees Celsius is 210 Cps
200Cps @ 22 degrees Celsius is 200 Cps
200Cps @ 32 degrees Celsius is 190 Cps

Associated label 1st batch 2nd batch 3rd batch
WT Cps Cps Cps
15 - - 160
20 203 - 215
25 - 317 325
30 355 340 370(Losi)
35 - 450 510
40 512 - 525
80 1048 - -
Calibration oil 100 102 102 102

The table above shows measurements from Associated silicone oil (and one from Losi). You can see that from different batches these oils are not the same value. This means that you will have no certainty about the real viscosity you put in your shocks. We have not tested Losi's Certified silicone oil yet as this was the answer from them to have constant viscosity. But still there the rating is WT and not Cps, even though they make the steps smaller to 2.5 WT for the certified oil.


Kyosho

label Cps
250 244
300 302
350 351
400 411
450 -----
500 506

The table from Kyosho silicone oil is the last batch tested on 12-11-2000 and is OK and is within all tolerances we need in modelcar racing. As this was the third batch tested the past four years we can certify that this oil is OK also the thick ones from 1000 and higher.

If there is a factory that can provide oil for testing we can arrange this to see if the product reaches the specification claimed!

Which manufacturer use which rating?
Which manufacturers you can use same rating oil?
Only manufacturers using Cps as rating are using a world standard and can be mixed used.
Other ratings like W and WT might differ from brand from brand!

shock oil differential oil
Brand values label rating linear values in Cps values label rating
Kyosho 100 - 900 Centipoise Cps 1.000 - 60.000 Centipoise Cps
Mugen 100 - 900 Centipoise Cps 1.000 - 60.000 Centipoise Cps
Associated 10 - 80 WT no no
Losi 10 - 100 WT no no
Orion 10 - 80 No rating printed only numbers like 40/400 no no
Xray 100 - 900 W 1.000 - 60.000 W
GS-Racing USA 20 - 60 WT 1.000 - 50.000 Centipoise Cps
GS-Racing Europe 200 - 900 Cps 1.000 - 50.000 Centipoise Cps
Crono ? ? ? ?
Serpent 20 - 50 W no no no
Thunder Tiger ? ? ? ?
Trinity ? ? no no


Just pasted some stuff from that link, dont know if it helps you in any way

daytona7

Thanks Automan! Hope the masters that be here keep this post up front permanently as it is by far the most informative of all.

gonsped69

My Feedback: (6)

Pardon my ignorance or lack of understanding but is Automan referring to the shock oil in a way such that , for example the FG shock oil 5000 wt rating = a 500WT bottle of Associated shock oil? (which does not exist of course) or a 50WT shock oil?

i.e. Cannot use nitro 8th scale buggies shock oils in FG cars/trucks?

I'd love to get genuine FG products for my cars but availability is well....not quite there, where if I can pop in my local hobby shop and pick up the nitro shock oils, it is a lot more convenient.

hoppy504

It could be worth trying motorcycle synthetic fork oil. I have seen this in the Uk in SAE5 and SAE10

grades. How this compares to model car grade figures is anyones guess, but it has controled some

heavy bikes in my life.

john.

Automan

gonsped: If you read little closer, you should have noticed that it's not my information, i just copy/pasted it for him so he could read... he had problems getting the url to work. I didn't read trough it carefully, just pasted it cause it seamed to be good information.

About the shockoil, why not just buy some bottles of fg oil, take some low and middle and high numbers and try for your self what feels good. To save money try some bottles from the lower region like 500 and up, just a hint.

If that is to expensive then you can buy a thin shockoil like redline light 5w or something like that, and mix it with that standard oil in the shocks, works very good.

I have bought some different shockoil from fg and others, but i started with buying a bottle of redline light 5w oil and mixed that up with the standard oil in the shocks about 50/50, feels smooth and nice now.
I did that because i had to wait so long for the fg oil to come that i did my own mix.... was so good that i still use it and haven't touched my fg oil yet and if someone say it is wrong or it wont work or something like that... thats just stupid, of course it works mixing these kind of oil, it is no problem at all and wont have any lower quality either if you use good brands.


Btw, daytona7.. if you like to know something else just pm me, and i will try to help you.

daytona7

A lot of the 1/4 scale racers have been using fork oil for years. If I remember correctly, someone once said that Silicon oil has a tendency to foam up easy due to the 32 pound weight of the cars. Had thought of giving it a try but have to get new "O" rings for the shocks and see how the 55 wt Trinity and 40 wt red Serpent oils work first. Have 5 to 30 wt fork oil. Any Aussie's here who know any of the 1/4 scale sprint car racers down under to see what they are using?

Automan

Yes, there is absolutely no need to buy fg's shock oil. just visit your favorite car shop and they will probably have a few brands to choose from, look on it if possible how thick or thin it seams to be, try a few and if you got one thats to thin and maybe one thats a littlebit to thick, same brand there is no problem mixing them at all... and if you buy two separate brands there should be no problems mixing them either.

When buying as daytona7 said fork oil (btw,i think my redline oil was a forkoil) or similar at your local car shop, you get allot more oil for around the same money and probably much higher quality then fg's own shockoil, just a suggestion to you who haven't tried it yet.

JRexA

At the moment I am using some 700CPS Protech oil in my Leopard Race. It is definately thinner than the oil that was in the shocks, and than the 3500 cps FG oil that I also have.

Makes the suspension work more, and I had to tighten the springs a bit, not to bottom out.

I was trying o find some fork oil, but as MC's are banned in Greenland, We don't have anyone that stocks fork oil.

daytona7

Have you tried any snowmobile shops if they are allowed? Also, do you know anyone on the military bases? Possibly they might have access to some other oils in the same grade.

daytona7

Tried Trinity 55 wt rear and Serpent 40 red wt front. TOO bouncy just on grass. Will have to try my fork oil to see what the difference would be. If anyone is using hydraulic brakes on their cars, you know that Mineral Oil works just as good as FG oil and is a lot cheaper.

JRexA

Daytona7: Thanks for the Tip, I will try asking the Snowmobile shops. But I think they just tell their customers to replace the entire shock.

daytona7

Normally when one replaces or changes fork oil, there is always some left in the bottles to be able to fill our shocks.