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Suspension Fluid Viscosity

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A while back, I discovered that listed weights don't mean a whole lot when it comes to suspension fluid. I found a great list containing just about every suspension oil out there, with associated actual viscosity. I couldn't get the fluid I wanted to do my shock, but was able to mix up a custom fluid to get where I needed to be using was was locally available. Anyway, I doubt most folks know that 5wt from one brand has little to do with 5wt from another, etc. I did about 30 seconds of searching and found a couple of relevant viscosity charts - might be of interest to some:

http://www.peterverdone.com/archive/files/suspension%20oils.pdf

http://www.hrpworld.com/client_images/ecommerce/client_39/products/pdf_3119_1.pdf

JayC

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the real question is at was temp do you compare? the 40c is close to room temp so may be better? or the 100c may be closer to a warm working fluid but forks don't ever get that hot?

it is interesting how they compare though.

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the real question is at was temp do you compare? the 40c is close to room temp so may be better? or the 100c may be closer to a warm working fluid but forks don't ever get that hot?

it is interesting how they compare though.

It really the relative data that is interesting. For example, if somebody was set up using Castrol 10wt (which is really closer in viscosity to most of the 5wts) then did a fluid change with Bel Ray 10wt, they'd be in for an unpleasant surprise.

I had to change fluid brands due to availability, and used a similar set of data to get the viscosity I needed with the brands that were readily available.

JayC

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if you ever use the same oil you havnt the problem.

when a rider want revalve the fork you have the stock stack and know the oem oil.

if you use different oil , know the difference beetwen kyb then maxima or showa red

and you revalve done!!the problem born when a rider like a suspension with unknow oil and he want change it only without valving mod. if his fork use a real stiff 7w(and you don t know it) and change with a 5w light (4.2w) .the rider feel the fork soft on ls

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Keep in mind some oils last longer than others. There are very few people who change their suspension fluid anywhere near often enough. Just like race fuel and octane- there is much more to it than that one specification.

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if you would have done a search,the peter verdone stuff has been beaten to death on this forum,but it is very helpful if you need some oil info.

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that's an old list, I'd try to research the oil properties from more current data before I'd make any big change based on the charts.

Also most those company's don't make oil, they blend and bottle product that they buy mostly on bid (low bid). So the base oils could easily change batch by batch.

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tried it, made the clickers range of adjustment very limited,

Thanks for posting the charts, I need to find some RedLine Like Water!

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Anyone notice those two charts have different weights for the same oils?

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A thorough servicing can give similar results even with the exact same oil as the original.

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Compared to the way my forks felt before I put the 5w in: hard, unresponsive....

I was touching on what MXTuner said. You put in 5wt, what was in it before to compare with? Thanks.

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I found my click adjustments to not be of alot of value, I had washing out, especially on downhills, rough ones, where the fork was just not reacting fast enough to keep the tire in contact with the ground and thus, in control. I clicked out/off ALL the rebound damping, still no help, replaced the stock fork fluid with ATF fluid, AHA got some improvement, so I replaced the ATF with some Maxima 5wt....VIOLA, today, I felt like I was riding someone else's bike, my front end is more plush AND it stays in contact with the dirt more, giving me more feedback and NO washouts!. I actually have some BelRay 2.5w coming in the mail, when it's time to service my forks, I'm gonna try it, because my forks are still stiffer on rebound than my rear shock. In the pic below, my forks were in the red circle with too much rebound damping, now they are in the green circle with lighter rebound damping, I have more control, more traction and they are more plush, by maxxing out the clicker AND putting in thinner oil. 2010 Husky TE450 with stock KYB forks

ReboundDamping.jpg.

DSCN1501.jpg

Edited by OlderHuskyRider

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I found my click adjustments to not be of alot of value, I had washing out, especially on downhills, rough ones, where the fork was just not reacting fast enough to keep the tire in contact with the ground and thus, in control. I clicked out/off ALL the rebound damping, still no help, replaced the stock fork fluid with ATF fluid, AHA got some improvement, so I replaced the ATF with some BelRay 5wt....VIOLA, today, I felt like I was riding someone else's bike, my front end is more plush AND it stays in contact with the dirt more, giving me more feedback and NO washouts!. I actually have some BelRay 2.5w coming in the mail, when it's time to service my forks, I'm gonna try it, because my forks are still stiffer on rebound than my rear shock. In the pic below, my forks were in the red circle with too much rebound damping, now they are in the green circle with lighter rebound damping, I have more control, more traction and they are more plush, by maxxing out the clicker AND putting in thinner oil. 2010 Husky TE450 with stock KYB forks

ReboundDamping.jpg.

Really like the graph! Would you happen to have one for compression damping?

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I found my click adjustments to not be of alot of value

This is the problem with KYB oil if you have too many hours on it, it became like snot and makes the fork harsh and rebound slow

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I found my click adjustments to not be of alot of value, I had washing out, especially on downhills, rough ones, where the fork was just not reacting fast enough to keep the tire in contact with the ground and thus, in control. I clicked out/off ALL the rebound damping, still no help, replaced the stock fork fluid with ATF fluid, AHA got some improvement, so I replaced the ATF with some BelRay 5wt....VIOLA, today, I felt like I was riding someone else's bike, my front end is more plush AND it stays in contact with the dirt more, giving me more feedback and NO washouts!. I actually have some BelRay 2.5w coming in the mail, when it's time to service my forks, I'm gonna try it, because my forks are still stiffer on rebound than my rear shock. In the pic below, my forks were in the red circle with too much rebound damping, now they are in the green circle with lighter rebound damping, I have more control, more traction and they are more plush, by maxxing out the clicker AND putting in thinner oil. 2010 Husky TE450 with stock KYB forks

ReboundDamping.jpg.

DSCN1501.jpg

Great post, thank you.:lol:

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