Fork Oil Recommendation

[Just Passing Thru]

Posting for a friend who'd like me to do a fork oil change...

Hello,

What is the Owner's Manual recommendation (I don't have a manual in front of me) as to what grade of fork oil to use in an FJR 1300, and what do owners recommend; going higher or lower in viscosity?

 

[exskibum]

Posting for a friend who'd like me to do a fork oil change...
Hello,

What is the Owner's Manual recommendation (I don't have a manual in front of me) as to what grade of fork oil to use in an FJR 1300, and what do owners recommend; going higher or lower in viscosity?

Timely, because I'm in the midst of doing this operation on my FJR again. Forks are off right now, and I'll be dumping, flushing and refilling them as time allows in the next day or two, before reinstalling. Here's what I use: Pro Honda Suspension fluid SS-7 (5W) and SS-8 (10W) mixed in equal parts (50-50) to give 7.5W.

 

[Geezer]

There is no standard for viscosity of suspension oils. Here is a chart which will make some sense out of the various brands. It is kind of old but is probably still good.

I have been using Silkolene PRO RSF 2.5W for a couple of years and it works well for me. There are plenty of good fork oils, but don't assume a 5w or 10w is the same from brand to brand.

 

[exskibum]

don't assume a 5w or 10w is the same from brand to brand.

Exactly. That's pretty much why I started with something I'd been using (Pro Honda) and adjusted the viscosity from there (from their 10W to an effective 7.5W).

 

[charismaticmegafauna]

...and what do owners recommend; going higher or lower in viscosity?

The reccos from the (above) guys are all good.

You'll know if you chose a too viscous oil -- very uncomfortable (especially when cold). :angry:

I'd recco (unless racing or something else/sidecar...?) to err on the light/less viscous side.

 

[Patriot]

I'm a fan of BelRay fork oil

 

[JamesK]

Is there a fork oil brand someone is/has used where they can vouch for the weight, i'm trying to find a quality fork oil, preferably synthetic that is actually a 5Wt, since that's what my GMD fork kit recommends.

I'm leaning towards the Maxima racing fork oil 5wt.

I saw Jeff Ashe mention in another thread that from his experience the Maxima oils are very good, synthetic and the weights are "what it says on the box"

https://www.maximausa.com/products/suspension/forkoil.asp

More info:

Just spoke to the folks at Maxima and they confirmed that their fork oils are rated correctly, per OEM specs. They also advised that their Racing Fork Fluid is far better to use in MC forks. However, they did say that their oils are mineral, not synthetic, but in a closed system like a fork that from their experience makes no perceivable difference.

 

[charismaticmegafauna]

Is there a fork oil brand someone is/has used where they can vouch for the weight, i'm trying to find a quality fork oil, preferably synthetic that is actually a 5Wt, since that's what my GMD fork kit recommends.

Don't they sell fork oil (or, recco a brand)?

The chart 'Geezer' linked to (above) is a good place to start.

Even knowing the accurate viscosity, in centistokes, at a given temperature will not insure that viscosity remains somewhat constant with varying temps (viscosity index). Silicone fluid has the property of remaining constant viscosity over widely varying temps.

More info:Just spoke to the folks at Maxima and they confirmed that their fork oils are rated correctly, per OEM specs. They also advised that their Racing Fork Fluid is far better ...

It's not unusual for a sales-rep. to promote their products ... :blink:

just sayin'....

What is the Owner's Manual recommendation ... as to what grade of fork oil to use in an FJR 1300,

From the FSM: suspension oil "01"....(or equivalent).

and what do owners recommend; going higher or lower in viscosity?

I don't know about other owners -- but, heavier fork oil (thicker viscosity) often makes for rough/harsh riding. Unless you've got some specific situations: racing, side-car, heavy loads, etc. -- I wouldn't recco heavier oil. In fact, lighter is often nicer -- as long as damping (adjustable) is still adequate.

In lieu of any better recommendation or spec'd fork oil availability -- ATF is often a good choice (maybe even -- synthetic ATF...).

 

[JamesK]

GMD mentioned many of the popular brands, Maxima, Motorex, Spectro, etc as long as these are around the 5Wt (racing oils), so not much specific help there.

I'm a big fan of AMSOIL synthetic oils, found them to be better than Motul, etc in engine oils.

AMSOIL also makes a synthetic suspension oil which is about 40% cheaper than the Motul equivalent, has anyone here used their AMSOIL Shock Therapy Suspension Fluid #5 Light - given my very favorable experience with the AMSOIL engine oils i'm thinking of giving that a try.

 

[UHOH]

I just changed and used the Honda 5W oil in my change. Wish I'd used 10W.

 

[Zorlac]

https://www.7thgear.net/7thGear/Portals/0/ForkOils.pdf